EBCS-10 Ethiopian Building Code Standard ELECTRICAL INSTALLATION OF BUILDINGS FOREWORDTheProclamationto definethepowersanddutiesof theCentralandRegionalExecutiveOrgansof theTransitionalGovernmentof EthiopiaNo.41/1993empowerstheMinistryof WorksandUrbanDevelopmentto preparetheCountry'sBuildingCode,issueStandardsfor designandconstructionworks,andfollowupandsupervisetheimplementationof same.In exerciseof thesepowersandin dischargeof itsresponsibility,theMinistryis issuingaseriesof BuildingCodeStandardsof generalapplication.The purposeof thesestandardsis to serveas nationallyrecognizeddocuments,theapplicationof whichis deemedtoensurecomplianceof buildingswiththeminimumrequirementsfordesign,constructionandqualityof materialssetdownbytheNationalBuildingCode.The majorbenefitsto be gainedin applyingthesestandardsaretheharmonizationofprofessionalpracticeandtheensuringof appropriatelevelsof safety,healthandeconomywithdueconsiderationof theobjectiveconditionsandneedsofthecountry.As thesestandardsaretechnicaldocum~ntswhich,bytheirverynature,requireperiodicupdating,revisededitionswill beissuedbytheMinistryfromtimetotimeas.appropriate.TheMinistrywelcomescommentsandsuggestionsonallaspectoftheEthiopianBuildingCodeStandards.All feedbackreceivedwill becarefullyreviewedbyprofessionalexpertsin thefieldof buildingconstructionwith a view to possibleincorporationof amendmentsin futureeditions.HaileAssegidieMinisterMinistryof WorksandUrbanDevelopment1995INTRODUCTIONThisCodeStandardfor theElectricalInstallationof Buildingsispartof theBuildingCodeof Ethiopia:This CodeStandardfor theElectricalInstaijationof Buildingsis mairilyadoptedfromlEE RegulationsforElectricalInstallationsandCanadianElectricalCode,Part 1,to suittheEthiopianconditions.Otherpublicationsquotedareshownin therespectivesectionsof the Code andtheEthiopianAuthorityfor Standardizationmaintainsregistersof anumberof foreignnationalandinternationalstandards.The Codeembr~cesseveralaspectsof electricalinstallationworkandsetsstandardsandprovisionsfor safeutilizationof electricity.The TechnicalCommitteefor CodeStandardsfor theElectricalInstallationof BuildingscomprisesofthefollowingInstitutionsrepresentingbalancedinterestofallsegmentsofthepublicconcernedwiththesubjectmatter: Ministryof Works&UrbanDevelopment(MWUD) BuildingDesignEnterprise(BDE) EthiopianElectricLight&PowerAuthority(EELPA) AddisAbabaUniversity,Facultyof Technology(AAU) EthiopianAuthorityfor Standardization(BAS).---' .--------- - ---ETHIOPIAN BUILDING CODE STANDARDEBCS-10 ELECTRICAL INSTALLATION OFBUilDINGSTABLE OF CONTENTSSection1 ScopeAnd Definitions1.1 Scope 11.2 Nonnativereferences 11J Defmitions 2Section2 Gen~ralRequirements2.1 Administrative 202.1.1 Authorityforrules i . i 202.1.2 Pennit 202.1.3 Applicationfor inspection 202.1.4 Postingof pennit ', , 202.1.5 Notificationre-inspection 202.1.6 Plansandspecifications 212.1.7 Connectionauthorization 212.1.8 Re-inspection 212.1.9 Renovationof existinginstallation 212.1.10 Useof approvedequipment 222.1.11Deviationorpostponement 222.1.12Powersof rejection 222.1.13Installationof electricalequipment 222.1.14Damageandinterfer.~e 222.2 Technical 232.2.1 Conventionalsymbols '.' 232.2.2 Co-ordination 232.2.3 Locationandrequirementof substation 232.2.4 Rooms(spaces)required 232.2.5 Locationandrequirementsof distributionboards 242.2.6 Locationandrequirementsof PBX/PABX rooms 242.3 Planninganddesigning 252.3:1 General 252.3.2 Layoutandinstallationdrawing 252.3.3 Design 252.4 Markingof equipment ' 262.4.1 General , , 262.4.2 Workmanshipandmaterials 272.4.3 Materialfor anchoring 272.4.4 Protectionof personsandproperty ,. 272.4.5 Maintainability , 272.4.6 Enclosures ,. 28Section3 Illumination3.1 Scope 293.2 Normativereferences 293.3 Definitions , 303.4 Lightingrequirements 353.4.1 IllumiQance ' 353.4.2 Luminance '.. ' 353.4.3 Glare' ' 363.4.4 Light directionandmodelling 363.4.5 Colour rendering , .. , 363.5 Emergencylightingrequirements 373.5.1 Escapelighting 373.5.2 Safetylightingfor particularhazardousworkplaces 373.5.3 Standbylighting 383.6 Lightingrequirementsfor varioustypesof buildings 383.6.1 General 383.6.2 Industrial 393'.6.3 Offices.,., ' ' 393.6.4 Hotelsandrestaurants, 393.6.5 Educationalestablishments.' 403.6.6 Hospitals , 403.7 Outdoorlightingrequirements 423.7.1 Illuminance , , 423.7.2 Colourr~nderinggroup 423,7.3 Limitationof glare : ' .' , 433.7.4 Lightingof outdoorfixedlocationwork spaces 43IISe~tion4 Conductors4.1 Scope ',' ' 66.4.2 Nonnativereferences 664.3 Definitions 674.4 Size of conductors 694.4.1 Ph~econductorsin a.c.Circuitsandliveconductorsin d.c.circuits.. 694.4.2 Neutralconductors , 694.5 Ampacityof wires,cablesandflexiblecords 704.5.1 Conductoroperatingtemperature 704.5.2 .Cablesconnectediri parallel 704.5.3 Cablesconnectedto bareconductorsor busbars 70'4.5.4 Voltagedrop ~ 704.6 Flexible cords ' 704.7 Colour of conductors '.' : 714.8 Maximumpermissibletemperll,ture 71Annex (preface)AnnexA (Normative)- CorrectionfactorsAnnexB (Normative)- Typeof cableandampacitySection5 ServiceAnd ServiceEquipment7485905.i Scope ' 1415.2 Normativereferences '.' 1415.3 Definitions 1415.4 Generalrequirements ' ' 1425.4.1 Numberof servicespermitted 1425.4.2 Consumer'sinstallationnottobesuppliedthroughanotherbuilding 1435.4.3 .conductorsconsideredoutsideof a building 1435.4.4 Other'conductorsin racewayor cable 1445.4.5 Clearancefrombuildingopenings 1445.5 Serviceequipment 1445.5.1 General 1445.5.2 Control .. 145III5.6 Wiring methods 1485.6.1 Undergroundconsumer'sserviceconductors 1485.6.2 Overheadconsumer'sserviceconductors 1485.7 Meteringequipment 1495.7.1 Connection 149Section6 CircuitLoadingandDemandFactor6.1 Scope 1506.2 Normativereferences 1506.3 Defmitions 1506.4 General 1516.4.1 Currentcalculation 1516.4.2 Voltagedrop 1516.4.3 Maximumcircuitloading 1516.4.4 Useof demandfactor 1516.5 Servicesandfeeders 1516.5.1 Single-familydwellings 1516.5.2 Apartmentandsimilarmulti-familybuildings , 1526.5.3 Schools 1536.5.4 Hospitals 1536.5.5 Hotels,motels,dormitories,andbuildingsof similaroccupancy 1546.5.6 Othertypesof occupancy 1556.5.7 Branchcircuits 1556.5.8 Feederdemandfactorsfor lifts 155Section7 Earthing,Bonding,andLightningProtectionPart I - Earthing,andBonding7.1 Scope 1577.2 Normativereferences 1577.3 Systemand circuitsearthing 1587.3.1 Directcurrent.systems 1587.3.2 Alternating- currentsystems 158IV7.47,6Locationof systemearthingconnections 1597.4.1 D.C.systems 1597.4.2 A.C. systems 1597.4.3 Isolatedsystems , , , '.' 1597.4.4 Singleservicesupplytotwoormorebuildingsorstructures., 1607.4,5 Conductorstobeearthed , , 1607.4.6 Currentoverearthingconductor , , , , .. 160Bonding 1617.5.1 Non-currentcarryingmetalparts , , , 1611.5.2 Exposednon-current-carryingmetalpartsof equipment....... 1617.5.3 Non-metallicwiringsystems 1617.5.4 Non-electricalservices 1617.5.5 Extraneousfixedmetalwork 164Methodof earthing , , 1647.6.1 Effectiveearthing _ 1647.6.2 Commonearthingconductor , 1647.6.3 Commonearthingelectrode '. , , , . , 1647.6.4 Undergroundservice 1657.6.5 Shortsectionof raceway 1657.6.6 Fixedequipment , .. ', ,. 1657.7 Bondingmethods , . , 1667.7.1 CleansUifaee , 1667.7.2 Bondingatserviceequipment......................... 1667.7.3 Meansof assuringcontinuityatserviceequipment , 1667.7.4 Metalannourortapeof servicecable, 1677.7.5 Bondingatotherthanserviceequipment , 1677.7.6 Looselyjointedmetalraceways 1677.7.7 Bondingjumpers ,., , 1677.8 Earthingelectrodes.. , , 1687.8.1 General, , 1687.8.2 Servicepipeelectrode, , 1687.8.3 Artificialearthingelectrodes 169v7.9 Earthingandbondingconduc;tors 1717.9.1 General 1717.9.2 Installationof systemearthingconductors 1727.9.3 Installationof equipmentbondingconductors 1737.9.4 Earthingconductorsizefor d.c. circuits 1747.9.5 Earthingconductorsizefor a.c.system 1747.9.6 Bondingconductorsize 1747.10 Earthingandbondingconductorconnections 1757.10.1Bonding.conductorconnectionto raceways 1757.10.2 Earthingconductorconnectionto waterpipeelectrodes 1757.10.3 Earthingconductorconnectionstootherthanwaterpipeelectrodes.. 1757.10.4 Bondingconductorconnectionto circuitsandequipment 1767.10.5 EarthingconductorcQJ111Cctionto electrodes 176Section7 Earthing,BondingandLightninlZProtectionPart n-pghtningProtection7.11 Scope .' 1787.12 Normativereferences 1787.13 Definitions 1797.14 Materials 1807.14.1 General 1807.14.2 Galvaniccompatibility 1807.14.3 Corrosionprotection , 1817.14.4Mechanicalprotection 1817.14.5 Useof aluminium 1817.15 Form andsize 1847.15.1Air termination 1847.15.2 Conductors 1857.15J Earthtermination 1857.15.4 Minimumdimension 1857.16 Air termination 1857.16.1 General 1857.16.2 Support 1857.16.3 Metallicprojections 1857.16.4 Metallicmaterials 1867.16.5 Structurewithinzone.ofprotection ' 1867.16.6 Air terminationon roof 1867.16.7 Air terminationon reinforcedconcretestructure 186VI!7.17 Down conductor , , 1867,17.1 General ' , ' 1867.17.2 Routing , 1877,17.3 Recommendednumber ,., 1877.17.4 Mechanicalprotection 1877.17.5 Corrosivesoil .................................... 1877.17.6 Externalroutesnotavailable , , .. , ' 1877.17.7 Lift shafts , , , . , 1887.17.8 Re-entrantloops . , '.' 1887.17,9 Sharpbends , 1887.17.10 Bondingto preventsideflashing 1887.17.11 Bonds ' 1887.17.12 Testpoints , : 1897.18 Earthtermination ...................................... 1907.18.1 Termination, , , 1907.18,2 Resistanceto earth , ' , , . 1907.18.3 Earthelectrodes., , , . , .. , , . , .. , 1907.18.4 Connectionpoint .. ,.'.', , , , 1907.19 Commonearthing : . , , 1927.19.1 Commonearthpotential , 1927.19.2 Commonearthbonding , . , . 1927.20 Use of reinforcementfor earthingin concreteStructures.. , .. : .. , 1937.20.1 General, , , ,', . , . , , , , 1937.20.2 Electricalcontinuity . , . , , , , .. , , , .. , .. 193-7.20.3Prestressedconcretemembers ' , 1937.20.4 Precastconcretemembers ' .. , .. 1937.21 Structural~teelframingfor lightningprotection , '.,. 1947.21.1 General '.' ' ' . , . 1947.21.2 Air termination ,.,., 1947.21.3 Connection ' , 1947.21.4 Earthing .. , , , 1947.21.5 Interconnection , ,., ' 194Annex(Informative)AnnexA - Systemdesign 219AnnexB - Consultation , .. , 220VIISection8 Wiring Methods8.1 Scope 2238.2 Normativereference 2238.3 Generalrequirements 2238.3.1Methodsof-installatiOns 2238.3.2 Wiringinductsandplenumchambers , 2248.3.3 Undergroundinstallations 2248.3.4 Conductorsin hoistways 2258.4 Conductors 2268.4.1 Typesof conductors 2268.4.2 Radiiof bendsinconductors 2268.4.3 Conductorjointsandsplices 2278.4.4 Supportingof conductors 2288.5 Openwiring 2288.5.1Openandclippeddirect 2288.5.2 Spacingof conductors 2288.5.3 Conductorsupports 2298.5.4 Spacingof supports 22?8.6 Exposedwiringon exteriorof buildingsandbetweenBuildingsonthesamepremises 2298.6.1 Locationof conductors 2298.6.2 Clearanceof conductors 2298.6.3 Powersupplyconductors 2298.7 Barebusbarsandrisers 2308.8 Installationof boxes,cabinets,outletsandterminalfittings 2308.8.1 Numberof outletspercircuit 2308.8.2 Outletboxes 2318.8.3 Conductorsinboxes 2318.8.4 Terminalfittings , 2318.9 Cables,conductorsandwiringmethods 232AnnexA (Normative):Scheduleof methodsof installationof cables 233VIIISection Protection and Control9.19.29.3; 9.4I./9.59.69.79.89.9Section1010.110.210.310.4Scope 237Normativereferences ' 237Generalrequirements 2379.3.1 Protectiveandcontroldevices 2379.3.2 Typesandratingsof protectiveandcontroldevices 238Protectivedevices 2389.4.1 Overcu.rrentdevices 2389.4.2 Earthfaultprotection 239Fuses 240Circuit breakers 240Controldevices 240Switches 241Protectionandcontrolof miscellaneousapparatus 241Class1andClass2 CircuitsScope 245Normativereferences 245'Classification .10. 24510.3.1General 24510.3.2Class1extra-low-voltagepowercircuits 24610.3.3Class 2 low-energypowercircuits 24610.3.4Hazardouslocation 24610.3.5Circuitsto safetycontroldevices 24610.3.6Circuitsin communicationcables 246Class1circuits 24710.4.1Limitationof Class1 circuits 24710.4.2Methodsof installationfor Class1circuits 24710.4.3Overcurrentprotectionof Class1 circuits 24710.4.4Locationof overcurrentdevicesin Class1circuits .; 24710.4.5Class I extra-low-voltagepowercircuit~ourcesincludingTransfonners . 24810.4.6Conductormaterialandsizes 24810.4.7Insulatedconductorsfor Class1wiring ' 24810.4.8Conductorsof differentcircuitsin the,sameenclosure,cable,or Raceway 24810.4.9Mechanicalprotectionof remote-controlcircuits 24910.4.10 Class1circuitsextendingaeriallybeyonda building 249IX10.5 Class2 circuits , 24910.5.1Limitationsof Class2 circuits 24910.5.2Methods of installationon supply side of overcurrentprotectionorTransformersor otherdevicesfor Class2 circuits 25010.5.3Marking 25010.5.4Overcurrentprotectionfor Class2 circuits 25010.5.5Locationof overcurrentdevices ' 25110.5.6Conductorsfor Class2 circuitwiring 25110.5.7Separationof Class2 circuitconductorsfromothercircuits 25110.5.8Conductorsof differentClass2 circuitsin thesamecable,enclosure,orraceway 25210.5.9Penetrationofa fire separation 25210.5.10 Conductorsin verticalshaftsandhoistways ; . 25210.5.11 Class2 conductorsandequipmentin ductsandplenumchambers.. 25210.5.12 Equipmentlocatedontheloadsideof overcurrentprotection,transformers,orcurrent-limitingdevicesforClass2 circuits , , , 25210.5.13 Class2 circuitsextendingbeyonda building 25310.5.14 Undergroundinstallations , , 253Section11 Installationof ElectricalEquipment11.1 Scope 25411.2 Normativereferences , .., 25411.3 General , 25411.3.1Fusibleequipment ' 25411.3.2Connectionto identifiedterminalsor leads 25~11.3.3Equipmentovercombustiblesurfaces 25511.3.4Installationof ventilatedenclosures , '. 25511.3.5Outdoorinstallations 25511.4 Electricheatingandcookingappliances 25511.4.1Locationof non-portableappliances 25511.4.2Ratingof portableappliances 25511.4.3Applianceexceeding1500w 25611.5 Heatingequipment ; , 25611.6 Submersiblepumps 25611.7 Motorsandassociated,circuits 25711.7.1 Wiring methodsandconductors 25711.7.2 Overcurrentprotection 26011.7.3Overloadandoverheatingprotection 26211.7.4Undervoltageprotection ~ 26511.7.5Control 26611.7.6Disconnectingmeans 267x11.8 Air conditioningandrefrigeratingequipment '.' 26811.8.1General 26811.82 Branchcircuit 26811.8.3Disconnectingmeans 26911.8.4Supplycords , 26911.9 Storagebatteries ',' 26911.9.1Locationof storagebatteries 26911.9.2Ventilationof batteryroomsor areas 26911.9.3Batteryvents 26911.9.4Batteryinstillatio~ ' 26911.9.5Wiring ; .......... 270Section12 HazardousLocations12.1 Scope , ; 27912.2 Nonnativereference 27912.3 Classification 27912.3.1Division of ClassI locations ........................... 27912.3.2Division of ClassII locations 28012.3.3Division of ClassIII locations 28112.4 Generalrequirements 28112.4.1Electricalequipment 28112,.4.2Marking .. ' 28212.4.J Non-essentialelectricalequipment 28312.4.4Equipmentrooms ' 28312.4.5Cabletrays ; 28412.5 ClassI locations 28412.5.1Installationsin ClassI, Division 1 locations 284. 12.5.2Installat~onsin ClassI, Division 2 locations 28612.6 ClassII locations '.' 28712.6.1Installationsin ClassII, Division 1 locations 28712.6.2Installationin ClassII, Division 2 locations............... ~28912.7 ClassIII locations 29012.7.1Installationsin ClassIII, Division 1 locations 29012.7.2Installationsin ClassIII; Division2 locations 293XISection13 FhimmableLiquid DispensingandServiceStations,Garages,Bulk StoragePlants,FinishingProcessesandAircraftHangars13.113.213.3Scope 294Nonnativereferences 295Gasolinedispensingandservicestations 29513.3.1Hazardousareas 29513.3.2Wiring andequipmentwithinhazardousareas 29613.3.3Wiring andequipmentabovehazardousareas 29713.8 Aircraft;hangars.:. 0 0 o' 0 0 305Bulk storageplants ' 29913.6.1Hazardousareas : , .. 0 .' 299, .13.6.2Wiring and'eq~ipmentin hazardol,lsareas 30213.6.3Wiring andequipmentabovehazardousareas 302Finishingprocesses 0' 30213.7:1Hazardouslocations ,0 .. ; ........ 30213.7.2Wiring and'equipmentin hazardousareas 30413.7.3Wiring andequipmentaqove.hazardousareas .. 0 0 305Hazardousareas.. 0 .' .' 0 '. 0 , ' 305.... ..Wiring.andequipmentin,hazardous'areas... '0' o. : 0 306Wiring notwithin'hazardousarea. ' '.' 0.' 0 306Equipment-notwithinhazardous'areas 0 307Residentialstoragegarages 29813.5.1Non-hazardouslocation. 0 0 29813.5.2Hazardouslocation. ; 29913.5.3Wiring : 299Commercialgarages,repairsandstorage 29713.4.1 Hazardousareas 29713.4.2Wiring andequipmentinhazardousareas 29813.4.3Wiring abovehazardousareas 29813.4.4EqUIpmentabovehazarqousareas 29813.8.113.8.213.8.313.8.413.413.513.613.7Section 14'PatientCare'Areas14.1 Scope , 0 ' ,; 0 , 0 30814.2 Nonnativereferences ' : , 308XII14.3 Definitions 308'14.4 Circuitsin basiccareareas 31i14.4.1Branchcircuits '..... 31114.4.2Bondingto earthin basic-careareas ,31114.4.3Socketoutletsin basic-careareas ' '.' .: ' 31214.5 Circuitsin intermediateandcritical-careareas 31314.5.1Branchcircuits 31314.5.2Bondingto earthin intermediateandcritical-careareas '.' 31314.5.3Receptaclesin intermediate-andcritical-careareas 31314.6 Isolatedsystems ' 31414.6.1Sourcesof supply ' , 31414.6.2Single-phaseisolatedcircuits , : 31414.6.3Three-phaseisolatedsystems 31514.7 Essentialelectricalsystems ' 31514.7.1Circuitsin essentialelectricalsystems.. , ~ 31514.8 Transferswitches ,' 31614.9 Emergencysupply , 316Section 15 Installation of Lighting Equipment15.1 Scope : 31815.2 Normativereferences ' , . :.' .. '.' . ' 31815.3 Interiorlighting:quipment: '.' , . '.. ~.~.. , 31815.3.1General ' ' 31815.3.2Locationof lightingequipment........................ 32015.3.3Installation.of ligptingequipment ' 32315.3.4Wirin~of lighting.equipment .' ~ 32315.3.5Earthingof-lightingequipment : . ' 32615.3.6Electric-dischargelightingsystemsoperatingat 1000Vor less 32615.4 q~tdoorlightingequipment '.' ., , 32715..4.1 General, : 32715.4.2:Permanentoutdoorfloodlightinginstallation ; 3281,5.4.3'Exposedwirin~for permanentoutdoorlighting 331AnnexA (Normative).' ; .. , 334XIIISection16 Fire Alarm Systemand Fire. Pumps16.1 Scope , , ' ,:,. ~ , , , 34416.2 Normativereferences , , 34416.3 Definitions ',., -,' , , . , , , . , ........ ,'34416.4 Designconsideration.. , ~ , , .. : , .. , 346, .. . . '16.4.1General, , , .. , . , , , 34616.4.2, 'Section17 SignsandOutlineLighting..17.1'Scope ' 37117.2 Normativereferences 37117.3 Generalrequirements 37117.3.1' Construction 37117.3.2Disconnectingmeans 37217.3.3Ratingof.disconnectingmeansandcontroldevices 3/217.3.4Thermalprotection ' 37217.3.5Branch.circuitcapacity ' 37217.3.6Location ,':.'. : 37217.3.7Bonding ' ' 37317.3.8Protectionof signleads ' '.' 37317.3.9Installationof conductors : ' ' : 373. '17.3.10 Fuseholdersandflashers ' 37317.4 High-voltageluminousdischargetubesignsandoutlineLighting ' 37317.4.1Enclosure .' ~. '.. : .. '.: .. , ; .. 37317.4.2Protectionof uninsulat.edpart : , 37417.4.3Transformers : ' : .. 37417.4.4High-voltagewiringmethods '.< 375Section18 Lifts, Escalatorsand Similar Equipment18.1 Scope : .. ~ ' .' . '.' ' : : 37718.2 Normativereferences ,'.. , ,,'' 37718.3 General : ' : : 37718.3.1Voltage limitation ' 3i718.3.2Live partsenclosed,: ' 37718..4Conductors 378, , '18.4.1Installationof conductors 37818.4.2Minimumsizeof conductors 37818.4.3Motor circuitconductors 37918.5 Wiring : 37918.5.1Wiring methods 37918.5.2Branchcircuitsfor auxiliarysystems 380xvXVI18.6 Installationof conductors ' 38018.6.1Numberof conductorsin raceway ~ 38018.6.2Supports 38018.6.3Differentsystemsin oneracewayor travellingcable , 38018.6.4Wiring in hoistway 38118.6.5Electricequipmentin garagesandsimilaroccupancies 38118.6.6Sidewalklifts 38118.7 Travellingcables 381'18.7.1Suspension ~,_ 38118.7.2Hazardousjclassified)location 38218.7.3Protectionagainstdamage 38218.7.4Installation 38218.8 Disconnectingmeansandcontrol 38218.8.1General 38218.8.2Type : 38318.8.3Location 38318.8.4Phaseprotection , 38318.9 Overcurrentprotection..~ ; 38318.9.1Controlandopet~ltingcircuits 38318.9.2Motors 38418.10 Machineroom ; 38418.10.1 Guardingequipment 38418.10.2 Clearancearoundcontrolpanelsanddisconnectingmeans 38418.11 Earthing ' 38418.11.1 Metalracewayattachedto cars 38418.11.2 Electriclifts 38518.11.3 Non-electriclifts 38518.11.4 Methodof bonding 38518.12 Overspeed , 38518.12.1 Overspeedprotection 38518.12.2 Motor-generatoroverspeeddevice 38618.13 Emergencypower 38618.13.1 Supply 38618.13.2 Disconnection 38618.13.3 Hydrauliclifts disconnectingmeans 38618.14 Machineroomsandhoistwaypits lightingandAuxiliary 38618.14.1 Machineroom 386llU4.2 Hoistpits 387Section19 Theatrelnstallation19.1 Scope ; 38819.2 Normativereferences 38819.3 Wiringmethod 38819.4 Fixedstageswitchboard ' 38919.4.1Fuses 38919.4.2Overcurrentprotection :: 38919.4.3Dimmers 39019.4-4Controlof stageandgallerypockets : 39019.4.5Conductors 39019.5 Portableswitchboardon stage 39119.5.1Constructionof portableswitchboards 39119.5.2Supplyfor portableswitchboard 39119.6 Fixed stageequipment 39119.6.1Footlights 39119.6.2Metalwork 39119.6.3Clearanceatterminals 39219.6.4Mechanicalprotectionof lampsin borders,etc 39219.6.5Suspendedfixtures 39219.6.6Connectionsat lampholders 39219.6.7Ventilationfor mogullampholers, ~ 39219.6.8Conductorinsulationfor field-assembledfixtures 39219.6.9Branchcircuitovercurrenfprotection 39219.6.10 PendantlightsratedmorethanlOOW 39319.6.11 Cablesfor borderlights 39319.6.12 Wiring to arcpockets 39319.6.13 Socketoutletsandplugs 39319.6.14 Curtainmotors 39419.6.15 Flue dampercontrol 39419.7 Portablestageequipment 39419.7.1Fixtureson scenery 39419.7.2Stringor festoonedlights , - 39519.7.3Flexibleconductorsfr?m portableequipment 39519.7.4Portableequipmentfor stageeffects 395XVIISection20 EmergencySystems,Unit Equipment,andExit Signs20.1 Scope 39620.2 Normativereference 39620.3 General 39620.3.1 Adequatecapacity 39620.3.2 Instruction 39720.3.3 Batteriesmaintenance 39720.3.4 Lamps 39720.3.5 Circuits 39720.3.6 Methodof wiring 39720.4 Emergencysystems 39820.4.1 Supply 39820.4.2 Control 39820.4.3 Overcurrentprotection 39820.4.4 Audibleandvisualtrouble-signaldevices 39820.5 Unit equipment 39920.5.1 Mounting ,.. ' 39920.5.2 Supplyconnections 40020.6 Exit signs 40120.6.1 Powersupply 40I20.6.2 Wiring 401Section21 MotionPictureStudios,ProjectionRooms,Film ExchangesandFactory21.1 Scope 40221.2 Normativereferences 40221.3 General 40221.3.1 Wiring method 40221.4 Viewing, cuttingandpatchingtablefixture 40321.5 Film-vaultsandstoragerooms 40321.5.1 Equipmentin film vaultsandstoragerooms 40321.5.2 Wiring methodin film-vaults 40321.5.3 Lightingfixturesin film-vaults 40321.5.4 Film-vaultcircuits 404XVIII~_. ------ ~I21.6 Motion pictureprojectionrooms.. i 40421.6.1 Lampsin projectionrooms 40421.6.2Arc lampcurrentsupply 40421.6.3Ventilation 40421.7 Motorsandgenerators 404Section22 DiagnosticImaging Installation22.1 Scope 40522.2 Nonnativereferences ' 40522.3 Definitions 40522.4 High-voltageguarding 40622.5 Connectionsto supplycircuit 40622.6 Disconnectingmeans 40622.7 Transfonnersandcapacitors ; 40722.8 Control 40722.9 Ampacityof supplyconductorsandratingof overclirrentprotection 40822.10 Bonding 408Section23 ElectricalCommunicationSystems23.1 Scope - 40923:2 Nonnativereference 40923.3 General 40923.3.1Circuitsin communicationcables 40923.3.2Hazardouslocations 41023.3.3 Approvedtransfonners 41023.4 Insideconductors 41023.4.1Conductorsarrangement 41023.4.2 Insulation 41023.4.3 Earthingconductorswith anoutermetalcovering 41023.4.4 Separationfromotherconductors 41023.4.5 Penetrationof a fire separation 41123.4.6 Communicationcablein hoistways 41123.4.7 Communicationconductorsin ductsandplenumchambers 4.1223.4.8 Dataprocessingsystems 41223.4.9 Conductorsunderraisedfloors _ 41223.4.10 Conductorsin concealedinstallations 41223.4.11 TypeCFC under-carpetwiring system 413XIX23.5 Equipment 41423.5.1 Communicationequipmentin bathrooms 41423.5.2 Equipmentin air ducts,plenums,or suspendedceilings 41423.5.3 Exposedequipmentandterminations : 41523.5.4 Earthcircuits 41523.5.5 Communicationsystemsin hospitals 41523.6 Outsideconductors 41523.6.1 Overheadconductorsonpoles 41523.6.2 Overheadconductor$on roofs ~ 41523.6.3 Lightningconductors 41623.6.4 Swimmingpools 41623.7 Undergroundcircuits ; 41623.7.1 Directburiedsystems ' l .41623.7.2 Undergroundraceway ' ~ 41723.8' Earthing 41723.8.1 Bondingof cablesheath .' : 41723.8.2 Cable-sheathbondingconductor - A1823.8.3 Earthingelectrode '.. 41823.8A Earthingelectrodeconnection : 41923.8.5 Bondingof electrodes 419Section24.. CommunityAntennaInstallationFor Radio And televisionReception.24.1 Scope ',: : . ~ 420.24.2 Normativereferences'.: 42024.3 Technicalrequirements' 42124.3.1 Mechanical 42124.3.2 Electrical 42124.4 Equipment 42124.4.1 Communityantennadistributionamplifiersandotherpowersources . 42124.4.2 Exposedequipmentandterminations 42224.4.3 Equipmentearthing 42224.5 Communityantennadistributionnetwork : 42224.5.1 Conductor 42224.5.2 Voltagelimitation 42224.5.3 Hazardouslocations 423xx)24.5.4 Supports 42324.5.5Earthingof outerconductiveshield'ofa coaxialcable 42324.5.6Earthingconductor 42324.5.7Earthingelectrode 42424.5.8Earthingelectrodeconnection 42424.6 Conductorswithinbuildings~ ; ;' 42~24.6.1Separationfromother.~onductors ' .. ; ; .42424.6.2Conductorsina verticalshaft.. ; . ; ................ , 42524.6.3'Penetrationof aJire separation : ' 426'24.6.4CommuriityantennadistributionconductorsinductsandplenumCambers.. 426'24.6.5Raceways ' '.' .................. 42624.7 Conductorsoutsideof buildings : ' 42624.7.1Overheadconductorson poles ; 426.24.7.2Overheadconductorson roofs ',' 42624.7.3 Conductorson buildings ............................. 42624.7.4 Conductorsenteringbuildings 42724.7.5 Swimmingpools ' '. 42724.8 Undergroundconductors , .......................... 427. 24.8.1Directburiedsystems ' ; '~ 42724.8.2Undergroundraceway.............................. 428. 24.8.3.UndergroundbluckdIstribution 42924.9 Lightningarrestersfor receivingstations 42924.9.1 Lightningarrester 429. ,24.94 Earthingconductor 429.24.9.3Earthingelectrode 430AnnexA (Informative) 431---Section25 SwimmingPools,Fountainsand Similar Installations25.1 Scope ' 44625.2 Normativereference ' 44625.3 Definitions 44625.4 General 44725.4.1 Equipmentinstallation 44725.4.2 Overheadwiring 44825.4.3 Undergroundwiring 448XXI25.4.4 Bondingto earth 44925.4.5 Junctionanddeckboxes 45025.4.6 Transformersandtransformerenclosure 45125.4.7 Socketoutlets 45225.4.8 Luminariesandlightingequipment 45225.4.9 Earth-faultcircuitbreakers 45425.5 Permanentlyinstalledswimmingpools 45525.5.1 General 45525.5.2 Conduittype 45525.5.3 Circuit segregation 45525.5.4 Drainage 45525.6 Storableswimmingpools 45525.6.1 Electricalequipment 45525.6.2 Pumps ' 45625.7 Hydromassagebathtub 45625.7.1 Protection 45625.7.2 Control 45625.7.3 Otherelectricequipment 45725.8 Spasandhottubs 45725.8.1 Bondingto earth 45725.8.2 Controlsandotherelectricalequipment 45725.8.3 Leakagecurrent ~ 45825.8.4 Field-assembledunits 458Annex A (Informative) 460Section26 GraphicalSymbols26.1 Scope 46226.2 Normativereferences 46226.3 Definitions 462XXII26.4 Symbols 463AnnexA - (Infonnative) 470Annex B - (Infonnative) 471AppendicesAppendixI Inspectionandtesting A-IAppendix2 Fonnsof completionandinspectioncertificate A-9XXIII1.1 SCOPE1.2 NORMATIVE REFERENCES(2)ThisCodedoesnotapplyto:ETHIOPIAN BUILDING CODE STANDARDSCOPE AND DEFINITIONSa) IEC 364-1:1972 Electrical Installationsof Building, Part 1, Scope, Object andDefinitions.a) electrictractionequipment,b) electricalequipmentof automobiles,c) electricalequipmenton boardships,d) electricalequipmentin aircraft,e) publicstreet-lightinginstallations,f) installationsin mines,g) radio interferencesuppressionequipment,exceptso far as it affectssafetyof theinstallation,h) fixedwiring for telecommunication,signalling,controlandthelike,i) internalwiring-of apparatus,j) systemsfor distributionof energyto thepublic,or powergenerationandtransmissionfor suchsystems.ECTION 1(1)This Codeappliesto the design,selection,erection,~nspectionandtestingof electricalinstallationsfor residential,commercial,publicandindustrialpremisesincludingprefabricatedbuildings,constructionsites,exhibitions,fairs and othertemporaryinstallationsup to andincludinglOOO.OY a.c.or I500.0Y d.c.(I) Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardson ElectricalInstallationof Buildings.1 EBCS-10 1995ELECTRICAL INSTALLATION OF BUILDINGSb) lEC 50:1982c) BS 7671:1992d) C 22.1:1992InternationalElectrotechnicalVocabulary.Requirementsfor ElectricalInstallations,lEE Wiring Regulations,SixteenthEdition.CanadianElectrical Code, Part I, Safety Standardfor ElectricalInstallations,SixteenthEdition.(2) At thetimeof publicationof thisBuildingCodeStandard,theeditionsindicatedwerevalid.All referencesare subjectto revisions,andpartiesto agreementandbasedon this EthiopianBuildingCodeStandardareencouragedto investigatethepossibilityof applyingthemostrecenteditionsof the referencesindicatedbelow. The EthiopianAuthority for Standardizationmaintainsregistersof a numberof foreignnationalandinternationalstandards.1.3 DEFINITIONS(1) For thepurposeof thisCode,thefollowingdefinitionsshallapply.acceptableaccessible(asappliedto wiring methods). accessoryambienttemperatureampacityacceptabletotheAuthorityenforcingthisCode.not permanentlyclosedin by thestructureorfinish of the building and capableof beingremoved without disturbing the buildingstructureor finish.a device,otherthancurrent-usingequipment,associatedwith such equipmentor with thewiring of an installation.the temperatureof the air or othermediumwheretheequipmentis to beused.a steadyvalueof currentwhichcanbecarriedby a conductorunder specifiedconditionswithoutits steadystatetemperatureexceedinga specifiedvalue.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 2appliancearms'sreachbarrierbasicinsulationbondingconductorbranchcircuitbuildingvoid,accessibleSECTION 1: SCOPE AND DEFINITIONSanitemof current-usingequipmentotherthana luminaireoran independentmotor.a zoneof accessibilityto touch,extendingfrom anypointona surfacewherepersonsusuallystandor moveabout,to thelimitswhichapersoncanreachwithhis handin anydirectionwithoutassistance.a partprovidinga defineddegreeof protectionagainstcontactwith liveparts,fromanyusualdirectionof access.insulationappliedto live partsto providebasic protectionagainstelectricshockandexclusivelyfor functionalpurposes.aprotectiveconductorprovidingequipotentialbonding.that portion of the wiring installationbetweenthe finalovercurrentdeviceprotectingthecircuitandtheoutlet(s).a spacewithinthe structureor thecomponentsof a buildingaccessibleonlyatcertainpoints.buildingvoid,non-accessible a spacewithin a structureor the componentsof a buildingwhichhasnoreadymeansof access. ()bunchedcablesbusbusway3 EBCS-10 1995cablesaresaidto bebunchedwhentwoormorearecontainedwithin a singleconduit,duct,ducting,or trunkingor, if notenclosed,are not separatedfrom eachotherby a specifieddistance.a conductorwhich servesas a commonconnectionfor thecorrespondingconductorsof two or morecircuits..a raceway-consistingof metaltroughing(includingelbows,tees, crosses, in addifion to straight runs) containingconductors,theconductorsbeingsupportedon insulators.ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGScabinetcablebracketcablechannelcablecleatcablecouplercableductingcableladdercabletraycabletrunkinganenclosureof adequatemechanicalstrength,composedentirelyofnoncombustibleandabsorption-resistantmaterial,designedeitherfor surfaceor flushmounting,andprovidedwith a frame,mat,ortrim, in whichswingingdoorsarehung.a horizontalcablesupportsystem,consistingof elementsfixed atoneendonly, spacedat intervalsalongthelengthof thecableandon whichthecablerests.anenclosuresituatedaboveor in theground,ventilatedor closed,andhavingdimensionswhichdonotpermittheaccessof personsbut allow accessto theconductorsand/orcablesthroughouttheirlengthduringandafterinstallation.A cablechannelmayor maynot formpartof thebuildingconstruction.a componentof a supportsystem,which consistsof elementsspacedat intervalsalongthelengthof thecableor conduit.ameansof enablingtheconnectionor disconnection,atwill, of twoflexiblecables. It consistsof a connectoranda plug.amanufacturedenclosureof metalor insulatingmaterial,otherthanconduitor cabletrunking,intendedfor the protectionof cableswhicharedrawn-inaftererectionof theducting..acablesupportconsistingof aseriesof supportingelementsrigidlyfixed to main supportingmembers. The supportingelementsoccupylessthan10%of theplanarea.a cablesupportconsistingof a continuousbasewith raisededgesandno covering.A cabletrayis consideredto benon-perforated,wherelessthan30%of thematerialis removedfromthebase.a manufacturedenclosurefor theprotectionof cables,normallyofrectangularcross-section,of whichonesideisremovableorhinged.4 EBCS-1 0 1995 ETHIOPIAN BUILDING CODE STANDARDETHIOPIAN BUILDING CODE STANDARDSECTION 1: SCOPE AND DEFINITIONSa protectiveconductorconnectingexposedconductivepartsof equipmentto themainearthlingterminal.5EBCS-10 1995equipmentin which protectionagainstelectricshockdoes not rely on basic insulationonly, but whichincludes means for the connection of exposedconductivepartsto a protectiveconductorin thefixedwiring of theinstallation.a devicecapableof making,carryingand breakingnormalloadcurrentsandalsomakingandautomaticallybreaking,underpredeterminedconditions,abnormalcurrentssuchas short-circuitcurrents. It is usuallyrequiredto operateinfrequentlyalthoughsometypesaresuitablefor frequentoperation.anenclosure(corridor)containingsupportingstructuresfor conductorsand/orcablesand joints and whosedimensionsallowpersonsto passfreelythroughouttheentirelength.a circuit-breakerthecontactsof whicharesoarrangedas to makeor breakall polessimultaneouslyor in adefinitesequence.a devicecomprisinga fuse elementor severalfuseelementsconnectedin parallelenclosedin a cartridgeusually filled with arc-extinguishingmedium andconnectedto terminations.Seefuselink.anassemblyof electricalequipmentsuppliedfrom thesameorigin andprotectedagainstovercurrentby thesameprotectivedevice(s).ClassI equipmentcircuitprotectiveconductor(CPC)circuit-breaker(linked)circuit-breakercircuitcartridgefuse linkcabletunnelELECTRICAL INSTALLAtiON OF eUILDINGSClassII equipmentconduitcutren/-permitconneC/orcontractorcurrent-carryingcapacityof a conductorcu'ent-usmgequipment6 EBCS-101995'equipmentin which protectionagainstelectricshockdoesnot rely on basic insulationonly, but in whichadditionalsafetyprecautionssuch as supplementaryJinsulationateprovided,therebeingnoprovisionfor theconnectionof exposedmetalworkof theequipmenttoa protective conductor, and no refianc-euponprecautionsto be taken in the fixed wiring of theinstallation.a partof aclosedwiring systemfor cablesin electricalinstallati()fis,allowing them to be drawn in and/orreplaced,butnot insertedlaterally.awrittenpetrfiissionfrom Authorityhavingjurisdictionto a supplyauthorityto theeffectthatelectricenergymaybesuppliedto a particularinstallation.thepartof a cablecoupleror of an appliancecouplerwhichis prOVidedwith femalecontactsandis intendedto be attachedto theendof the flexiblecableremotefromthesupply.any personwho as principal, servantor agent,byhimselfor his'associates,employees,servantsor agentsperfOIinSor engagestoperformeitherfor hisown useandberrefitOr for thatof 'anotherandfor o-rwithoutremunefationor gain any work with respectto anyelectricalinstallationor any otherwork to which thisCodeapplies.the maximumcurrentwhich can be carned by acowductotunderspecifiedconditionswithoutitssteadystatetemperatureexceedinga specifiedvalue.equipmentwhichconverfselectricalenergyintoanotherformof energy,suchaslight,heat,or motivepower.ETHIOPIAN BUILDING CODE STANDARDETHIOPIAN BUILDING CODE STANDARD 7EBCS-10 1995SECTIQN 1: SCQPE AND DEFINITIONSrisk of injury to persons(and livestockwhere expectedto bepresent)from:insulationcomprisingboth basic insulationand supp'lementaryinsulation.a) fire,electricshock,andbumsarisingfromtheuseof electricalenergy;b) mechanicalmovementof electric~llycontrolledequipment,insofar assuchdangeris intendedto bepreventedby electricalemergencyswitchingorby ~lectrical~witchingfor mechanicalmaintenanceof nop-electricalpartsof suchequipment.anassemblycontainingswitchingor prote~tivedevices(e.g.fusesor circuit-breakers)associatedwith oneor moreoutgoingcircuitsfedfromoneormoreincomingcircuits,togetherwithtenninalsfortheneutralaridprotectivecircuitconductors.it mayalso includesignallingandothercontroldevices. Meansof isolationmay beinclud~din theboardQrmaybeprovideds~parately.a) an itemof switchgear,b) an itemof controlgear,orc) a distributionboardthemagnitudeof thecurrent(r.m.s.valll,efor a.c.)to becarriedbythecircuitin normalservice.circuitcQnn~ctingtheoriginof theinstallationto:contactof perSOnSor livestockwith livepartswhichmayresultinelectricshock.A distributioncircuitmayalsoconnecttheoriginof an installationto an outlying building or separateinstallation,when it issometimescalleda sub-main.to which one or more final circuits or itemsof currentusmgequipmentareconnected.(~eealsofinal circuit.)directcontactdesignc14rrent(of a circuit)dangerdistributionboarddistributioncircuitdoubleinsulationELECTRICAL INSTALLATION OF BUILDINGSduct a closedpassagewayformedundergroundor in a structureandintende~to receiveoneor morecableswhichmaybedrawnin.ducting (seecableducting)earthearthelectrodetheconductivemassof theEarth,whoseelectricpotentialat anypointis conventionallytakenaszero.a conductoror groupof conductorsin intimatecontactwith, andprovidinganelectricalconnectionto, earth.earthelectroderesistancetheresistanceof anearthelectrodeto earth.earth-faultcurrent a faultcurrentwhichflows to earth.earth-faultloopimpedance theimpedanceof theearth-faultcurrentloopstartingandendingatthe point of earthfault. The earthfault loop comprisesthefollowiBg,startingatthepointof fault:(a) thecircuitprotectiveconductor;(b) theconsumer'searthingterminalandearthingconductor;(c) theearthreturnpath;(d) thepaththroughtheearthenneutralpointof thetransformerandthetransformerwinding;andthephaseconduCtorfromthetransformerto thepointof fault.earth-leakagecurrent a currentwhich flows to extraneous-conductive-parts,in a circuitwhich is electricallysound. This currentmay havea capacitivecomponentincludingthat resultingfrom the deliberateuse ofcapacitors.earthenequipotentialzone a zone within which exposed-conductive-partsand extraneous-conductive-partsaremaintainedatsubstantiallythesamepotentialby bonding,suchthat,underfault conditions,the differencesinpotential between simultaneouslyaccessible exposed andextraneous-conductive-partswill notcauseelectricshock.earthing theactof connectingtheexposed-conductivepartsof aninstallationto themainearthingterminalof an installation.8 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD-- -- --------~---------------------'---)electrodeboUer, electrodewaterheater equipmentfor theelectricalheatingof wateror electrolytebythepassageof anelectriccurrentbetweenelectrodesimmersedin thewateror electrolyte.SECTION 1: SCOPE AND DEFINITIONSemergencystopping emergencyswitchingintendedto stopa dangerousmovement.9EBCS-10 1995earthingconductor a protectiveconductorconnectingthemainearthingterminalof an installationto an earthelectrodeor to othermeansofearthing.electricallyindependentearthelectrodes earthelectrodeslocatedat sucha distancefrom oneanotherthatthemaximumcurrentlikely to flow throughoneof themdoesnotsignificantlyaffectthepotentialof theother(s).electricalequipment any item for such purposesas generation,conversion,transmission,distributionor utilizationof electricalenergy,such as machines, transformers,apparatus,measuringinstruments,protectivedevices,wiring materials,accessories,appliancesandluminaries.electricalinstallation anassemblyof associatedelectricalequipmentsuppliedfromacommonoriginto fulfil aspecificpurposeandhavingcertaincoordinatedcharacteristics.electricshock a dangerousphysiologicaleffectresultingfromthepassingofanelectriccurrentthrougha humanbodyor livestock.emergencyswitching rapidcuttingoff of electricalenergyto removeanyunexpectedhazardto persons,livestock,or property.enclosure a part providing an appropriatedegreeof protectionofequipmentagainstcertainexternalinfluencesand a defineddegreeof protectionagainstcontactwith live partsfrom anydirection.equipment(abbr., seeelectricalequipment).ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSequipotentialbonding electricalconnectionmaintainirigvariousexposed-conductive-partsatsubstantiallythesamepotential.equipotentialzone (seeearthenequipotentialzone).exposed-conductive-partaconductivepartof equipmentwhichcanbetouchedandwhichisnota livepartbutwhichmaybecomeliveunderfaultconditions.externalinfluence anyinfluenceexternaltoanelectricalinstallationwhichaffectsthedesignandsafeoperationof thatinstallation.extraneous-conductive-parta conductivepart liableto introducea potential,generallyearthpotential,andnotformingpartof theelectricalinstallation.faultfault currentfeederfinal circuitfIXedequipmentflexiblewiringsystema circuitconditionin whichcurrentflows throughanabnormalorunintendedpath. This mayresultfroman insulationfailureor thebridgingof insulation.Conventionallytheimpedancebetweenliveconductorsor betweenlive conductorsandexposedor extraneous-conductive-partsatthefaultpositionis considerednegligible.a currentresulting'froma fault.a conductoror groupof conductorsthattransmitelectricalenergyfromaservicesupply,transformer,switchboard;distributioncentre,'generator,or othersourceof supplyto branchcircuitovercurrentdevice.a circuit connecteddirectlyto current-usingequipment,or to asocket-outletor socket-outletsor other outlet points for theconnectionof suchequipment.equipmentfastenedto a supportor otherwisesecuredin specificlocation.a wiring systemdesignedto providemechanicalflexibility in usewithoutdegradationof theelectricalcomponents.10 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDfuncJionaJearthingfunctionalextra-Iowvolt4gefusefuseelementfuselin~hotairsaunaindirectcontactSECTION 1: SCOPE AND DEFINITIONSconnectionto earthnecessaryfor properfunctioningof electrical.equipment.any extra-lowvoltagesystemin which not all of the protectivemeasuresrequiredfor SELV havebeenapplied.adevicethatby thefusingof oneor moreof itsspeciallydesignedand proportionedcomponents,opensthe circuit in which it isinsertedby breakingthercurrentwhenthis exceedsa give~valuefor a sufficienttime. Thefusecomprisesall thepartsthatformthecompletedevice.a partof a fusedesignedto meltwhenthefuseoperates.a part of a fuse, includingthe fuse element(s),which requiresreplacementby a new or renewablefuse link afterthe fusehasoperatedandbeforethefuseis putbackintoservice.a roomor locationin whichair is heatedtoahightemperatureandin which the rekrtivehumidityis normallylow, rising for shortperiodsof timeonlywhenwateris pouredovertheheater.contactof personsor livestockwithexposed-conductive-partsmadelive by a faultandwhichmayresultin electricshock.installation(abbr.,seeelectricalinstallation).insulationisolationisoilltorladder(seecableladder)suitable non-conductivematerial enclosing, surrounding, orsupportinga conductor.a functionintendedto cutoff for reasonsof safetythesupplyfromall, or a discretesection,of the installationby separatingtheinstallationor sectionfrom~verysourceof electricalenergy.a mechanicalswitchingdevicewhich providesthe function ofisolation.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 11ELECTRICAL INSTALLATION OF BUILDINGSlivepartluminaireluminairesupportingcoupler(LSC)mainearthingterminalmechanicalmaintenanceEBCS-1 0 1995aconductoror conductivepartintendedtobeenergisedin nonnaluse,includinga neutralconductor.bquipmentwhichdistributes,filters,or transfonnsthelight fromoneor morelamps,andwhich includesanypartsnecessaryfor supporting,fixingandprotectingthelamps, but not the lamps themselves,and wherenecessary,circuit auxiliariestogetherwith the meansfor connectingthemto thesupply. For thepurposeofthe regulationsa lampholder,however,supportedisdeemedto bea luminaire.a means,comprisinganLSC outletandanLSC plug,providingmecl1a.n-malsupportfor a lu.minaireandtheelectricalconnectionto anddisconnectionfroma fixedwiring installation.a combinationof oneor morelow-voltageswitchingdevicestogetherwith associatedcontrol, measuringsignalling protective, regulating equipment, etc.,completelyassembledunderthe responsibilityof themanufacturerwith all the internal electrical andmechanicalinterconnectionand structuralparts. Thecomponentsof theassemblymaybeelectromechanicalor electronic.The assemblymaybeeithertype-testedor partiallytype-tested.the tenninalor bar providedfor the CC/lili'.:tlOnof}lrotectiveconductors,includingequipotentialbondingconductors,andconductorsfor functionalearthingifany,to themeansof earthing.the replacement,refurbishmentor cleaningof lampsand non-electricalparts of equipment,plant andmachinery.ETHIOPIAN BUILDING CODE STANDARDoverloadcurrent anovercurrentoccurringin a circuitwhich is electricallysound.nominalvoltage (seevoltage,nominal).originof an installation thepositionatwhichelectricalenergyis deliveredto anelectricalinstallation.13EBCS-10 1995SECTION 1: SCOPE AND DEFINITIONSa conductorconnectedto the neutralpoint of a systemandcontributing'to thetransmissionof electricalenergy.neutralconductorphaseconductor a conductorof an a.c. systemfor the transmissionof electricalenergyotherthana neutralconductor. The termalsomeanstheequivalentconductorof a d.c.systemunlessotherwisespecifiedinthisCode.permit theofficial writtenpermissionof theAuthorityhavingjurisdictionon a form providedfor the purpose,authorizingwork to becommencedon anyelectricalinstallation.overcurrentdetection a methodof establishingthatthe value of currentin a circuitexceedsa predeterminedvaluefor a specifiedlengthof time.obstacle a part preventingunintentionalcontactwith live parts but notpreventingdeliberatecontact.overcurrent acurrentexceedingtheratedvalue. For conductorstheratedvalueis thecurrent-carrying-capacity. plug a device,providedwith contactpins, which is intendedto beattachedto a flexible cable,and which can be engagedwith asocket-outletor with a connector.portableequipment electricalequipmentwhich is movedwhile in operationor whichcaneasilybemovedfromoneplaceto anotherwhile connectedtothesupply.point a terminationof the fixed wiring intendedfor the connectionofcurrent-usingequipment.ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSprotectiveconductor a conductorusedfor somemeasuresof protectionagainstelectricshockandintendedfor connectingtogetherany of thefollowingparts(referto Figure 1.1):prospectivefault current thevalueof overcurrentatagivenpointin acircuitresultingfroma faultof negligibleimpedancebetweenlive conductorshavingadifferenceof potentialunder normal operatingconditions,orbetweena live'conductorandanexposed-conductive-part.(a) exposedconductiveparts(b) extraneousconductiveparts(c) themainearthingterminal(d) earthelectrode(s)(e) theearthenpointof thesource,or anartificialneutral.;-an enclosedchanneldesignedexpresslyfor holdingwires,cables,or busbars,with additionalfunctionaspermittedin thisCode.a systemin which thenominalphaseto phasevoltagedoesnotexceed110.0Vahdthe nominalphaseto earth'voltagedoesnotexceed63.5V.singleinsulationappliedto live parts,whichproyidesa degreeofprotectionagainstelectricshockequivalentto doubleinsulationstandard.reducedlow voltagesysiemracewayreinforcedinsulation. 14 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 1: SCOPE AND DEFINITIONS4residualupet'atlngcurrent residualcurrentwhichcausestheresidualcurrentdevicetooperateunderspecifiedconditions.cpB MainearthingterminalM ExposedconductivepartC ExtraneousconductivepartP MainmetallicwaterpipeT EarthelectrodeE Othermeansof earthingzamechanicalswitchingdeviceor associationof devicesintendedtocausetheopeningof thecontactswhentheresidualcurrentattainsa givenvalueunderspecifiedconditions.the vector sum of the instantaneousvaluesof currentflowingthroughall live conductorsof a circuitata point in theelectricalinstallation.ProtectiveconductorscircuitprotectiveconductormainequipotentialbondingconductorsearthingconductOrsupplementaryequipotentialbondingconductors(whererequired)B1,2,3,4.1234Figure1.1Enmple of earthingarrangementsresidualcurrentresidualcurrentdeviceETHIOPIAN BUIL.DING CODE STANDARD EBCS-10 1995 15ELECTRICAL INSTALLATION OF BUILDINGSresistancearea(for anearthelectrodeonly)restrictiveconductivelocationringfinal circuitsafetyservice1iLVserviceshock (seeelectricshock).shockcurrentshort-circuitcurrentsimultaneouslyaccessiblepartsthesurfaceareaof ground(aroundanearthelectrode)on whicha significantvoltagegradientmayexist.a locationcomprisedmainlyof metallicor conductivesurroundingparts.withinwhichit is likelythatapersonwill comeintocontactthrougha substantialportionofhis body with the conductivesurroundingpartsandwhere the possibility of preventingthis contactislimited.a final circuit arrangedin the form of a ring andconnectedto a singlepointof supply.an electricalsystemfor electricalequipmentprovidedto protector warnpersonsin theeventof a hazard,oressentialto theirevacuationfroma location.an extra-low voltage systemwhich is electricallyseparatedfromEarthandfromothersystemsin suchaway thata singlefault cannotgive rise to therisk ofelectricshock.the conductorsand equipmentfor deliveringenergyfromtheelectricitysupplysystemto thewiring systemof thepremisesserved.a currentpassingthroughthe body of a personorlivestocksuchas to causeelectricshock and havingcharacteristicslikelyto causedangerouseffects.an overcurrentresultingfrom a fault of negligibleimpedancebetweenliveconductorshavingadifferencein potentialundernormaloperatingconditions.conductorsor conductivepartswhich can be touchedsimultaneouslyby apersonor, in locationsspecificallyintendedfor them,by livestock.16 EBCS-10 1995 ETHIOPIAN BUILDING'CODESTANDARDSECTION 1: SCOPE AND DEFINITIONSSimultaneouslyaccessiblepartsmay be Live parts, eXPQsed-conductive-parts, extraneous-conductive-parts, protectiveconductors,or earthelectrodes.socket-ouNet a device,providedwith femalecontacts,which is intendedto beinstalledwith thefixedwiring,andintendedto receivea plug. Aluminairetracksystemis not regardedasa socket-outletsystem.spur a branchfroma ring final circuit.stationaryequipment electricalequipmentwhich is eitherfixed,or equipmenthavingamassexceeding18.0kgandnotprovidedwith a carryinghandle.supplementaryinsulation independentinsulationappliedin additionto basic insulationinorderto provideprotectionagainstelectricshockin theeventof afailureof basicinsulation.supplyauthorityswitchswitch,linkedswitchboardswitchgearany municipal corporation,commission,company or personsupplying electrical power or energy intended for sale ordistributionto thepublic.a mechanicaldevicecapableof making,carryingand breakingcurrent under.normal circuit conditions,which may includespecifiedoperatingoverloadconditions,andalsoof carryingfor aspecifiedtimecurrentsunderspecifiedabnormalcircuitconditionssuchasthoseof short-circuit.It mayalsobe capableof making,butnotbreaking,short-circuitcurrents.a switchthecontactsof whicharesoarrangedasto makeor breakall polessimultaneouslyor in a definitesequence.anassemblyof switchgearwithorwithoutinstruments,butthetermdoesnotapplyto groupsof localswitchesin final circuits.an assemblyof main and auxiliary switching apparatusforoperation,regulation,protectionor othercontrolof an electricalinstallation.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 17ELECTRICAL INSTALLATION OF BUILDINGSsystemtemporarysupplyunitan electricalsystemconsistingof a single sourceof electricalenergyand an installation. For the purposeof this'Code, the.systemadoptedshallbe IT system.A systemhavingonepointofthesourceof energydirectlyearthen,theexposed-conductive-partsof the installationbeingconnectedto.earthelectrodeselectricallyihdependentof theearthelectrodesof the.source,(seeFigure1.2).an enclosurecontaining'equipmentfor the purposeof taking atemporaryelectricalsupplysafelyfroman itemof streetfurniture.trunking (seecabletrunking).voltage,nominal18 EBCS-10 1995voltageby which an installation(or part of an installation)isdesignated.Thefollowingrangesof nominalvoltage(r;m.s.valuesfor a.c.)aredefined:extra-low:Normally not exceeding50.0Y a.'C.or 120.0Yripplefreed.c.,whetherbetweenconductorsor to earth,low: Normally exceeding extra-low voltage but notexceedinglOOO.OYa.c. or 1500.0Y d.c. betweenconductors,-or 600.0Y a.c. or 900.0Y d.c. betweenconductorsandearth.The actualvoltageof theinstallationmaydiffer fromthenominalvalueby a quantitywithinnormaltolerance.ETHIOPIAN BUILDING CODE STANDARDESECTION 1: SCOPE AND DEFINITIONSSOURCE OF ENERJi1IL2L3~__ INSlAUAllOifARlH ELCCTROfl:-----,II,II,I,1.JEXPOSEDCONDUCTJVPARlSCONSUMERSJ'~'~.--I ,I II ,II EQUf'tolENl IN IINStALLAllON - I.r-III,II,L _INSlALLAlI~fAR1HELE:ClROOESOURCE EARlHETHIOPIAN BUILDING CODE STANDARDvoltagereduced (seereducedlow voltagesystem).an assemblymadeup of cableor busbarsandpartswhich secureand,if necessary,enclosethecableor busbars.19EBCS-10 1995wiringsystem.Figure1.2 TT SystemSECTION 29ENERAL REQUIREMENTS2.1 ADMINISTRATIVE2.1.1 AuthorityforRules(1) By virtueof theauthorityvestedin theAuthorityhavingjurisdiction,thisCodehasbeenadoptedandherebyordersanddirectsitsobservance.2.1.2 Permit(1) Electric~lcontractorsor othersresponsiblefor thecarryingout of thework shallobtainapermit from the Authority havingjurisdiction before commencingwork with respecttoinstallation,alteration,repair,or extensionof anyelectricalequipment.2.1.3 ApplicationforInspection(1) An applicationfor inspectionshallbefixedwiththeAuthorityhavingjurisdictionona formprovidedby the latteratthetimethepermitis obtained;2.1.4 PostingoCPermit(1) A copyof thepermitshallbepostedin aconspicuousplaceonthesiteof thework andshallnotberemoveduntil theinspectionis completed.2.1.5 NotificationRe-inspection(1) TheAuthorityhavingjurisdictionshallbenotifiedin writingbytheelectricalcontractor~atwork is readyfor inspectionatsuchtimeor timesaswill permitinspectionbeingmadebeforeanywork or portionthereofis commenced.20 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 2: GENERAL REQUIREMENTS2.1.6 PlansandSpecifications(1)Plansandspecificationsin duplicateor ingreaternumberif requiredbytheAuthorityhavingjurisdictiononecopyto beretainedby theAuthority,shallbe submittedby theowneror hisagentto, andacceptanceobtainedfrom,theAuthoritybeforework is commencedon:a) wiring installationsof publicbuildings,industrialestablishments,factories,andotherbuildingsin whichpublicsafetyis involved:b) largelightandpowerinstallationsandtheinstallationor apparatussuchasgenerators,transformers,switchboards,largestoragebatteries:c) suchotherinstallationsasmaybeprescribedby theAuthorityhavingjurisdiction.2.1.7 ConnectionAuthorization(I) Whereanyelectricalinstallationor partthereofto whichelectricalpoweror energyhasnotpreviouslybeensuppliedis madein or uponanylandbuildingorpremises,whereanyelectricalinstallationor partthereofhasbeendisconnectedor cutoff fromanyserviceor othersourceofsupplyunderthis Code,no supplyauthority,contractoror otherpersonshallconnector re-connectthe installationor partthereofto anyserviceor othersourceof supplyunless:a) theinstallationandall work in respectthereofhavebeeninspectedby an inspector;andb) aconnectionauthorizatiofthasbeenissuedbytheAuthorityhavingjurisdictionin respectof the installation.2.1.8 Re-inspection(1)The Authority havingjurisdictionreservesthe right to re-inspectat any time electricalinstallationnotwithstandinganypreviousinspectionandacceptance,if andwhenit considerssuc~actionto benecessary.2.1.9 Renovationof ExistingInstallation(1)TheAuthorityhavingjurisdictionmayrequiresuchchangesasmaybenecessarytobemadetoexistinginstallationswhere,throughhardusage,wearandtear,or asa resultof alterationorextensions,dangerousconditionshavedeveloped.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 21ELECTRICAL INSTALLATION OF BUILDINGS2.1.10Useof ApprovedEquipment(1) No oneshalluseanyelectricalequipmentotherthanapprovedelectricalequipmentof akindor typeandratingapprovedfor thespecificpurposefor which it is to b e employed.2.1.11Deviationor Postponement(1) 10 any casewheredeviationor postponementof this Code may be necessary,specialpermissionshallbeobtainedbefo~proceedingwiththework,butthisspecialpermissionshallapplyonly to theparticularinstallationfor whichit is given.2.1.12Powersof Rejection(1) Even thoughapprovalhaspreviouslybeengranted,theAuthorityhavingjurisdictionmayreject,atanytime,anyelectricalequipmentunderanyof thefollowingconditions:a) If the equipmentis substandardwith respectto the sample'on which approvalwasgranted.b) If theconditionsof useindicatethattheequipmentis notsuitable.c) If thetermsof theapprovalagreementarenotbeingcarriedout.2.1.13Installationof ElectricalEquipment(1) Electricalequipmentshallbe installedas to ensurethat,after installation,,thereis readyaccessto nameplatesandaccessto partsrequiringmaintenance.2.1.14DamageandInterference(1) No personshallinterferewithanyelectricalinstallationor componentthereofexceptwhen,in the courseof alterationsor repairsto non-electricalequipmentor structures,it may benecessaryto disconnector movecomponentsof anelectricalinstallations.(2) It shallbetheresponsibilityof thepersGiDiCarryingoutthelalterationsorrepairstoensurethattheelectricalinstallationis restoredto a safeoperatingconditionassoonastheprogressof thealterationsor repairwill permit.22 EBCS-1 0 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 2: GENERAL REQUIREMENTS1.1 TECHNICAL1.1.1 ConventionalSymbols(1)Graphicalsymbolsthat are to be usedin all drawings,wiring plans,etc for electricalinstallationsof buildingsshallbeasindicatedin Section26 of thisCode.1.1.1 Coordination(1)Propercoordinationand collaborationbetweenthe architect,building engineerand theelectricalengineershallbeeffectedfromtheplanningstageof theinstallation.(2)Theprovisionsthatwill beneededfor tile accommodationof substation,transformer,switchroom,lift wellsandotherappurtenantrooms,servicecableducts,risingmainsanddistributioncables,sub-distributionboards,openingsandchasesin floor andwallsfor all requiredelectricalinstallation,etc,shallbespecifiedin advance.2.1.3 .LocationandRequirementof Substation(1)Theideallocationof anelectricalsubsbttionfor a groupof buildingswouldbeattheloadcentreandshallbe locatedon thegroundfloor.(2) In multi-storeyedbuildings,thesubstationshallpreferablybe installedon thelowestfloorlevel,butdirectaccessfrom the streetfor installationor removalof the equipmentshall beprovided.The floor levelof thesubstationor switchroomshall!>eabovethehighestflood levelofthelocality.'In thiscase,theloadcentrewouldbesomewherebetweenthegeometricalcentreandtheair-conditioningplantroom.(3)Theavailabilityof powerlinesnearbymayalsobekeptin viewwhiledecidingthelocationofthesubstation.2.2.4 Rooms(Spaces)Required(I) In allocatingareaof a substation,it shallbenotedthattheflow of electricpower is fromsu~lycompany'sroomtohightensionroom,thento transformerandfinallytothelow voltageswitchgearroom. The layoutof roomsshallbe in accordancewiththis flow.ETHIOPIAN ,BUILDING CODE STANDARD EBCS-10 1995 23ELECTRICAL INSTALLATION OF BUILDINGS(2) The following roomsarerequiredin a substation:a) SwitchgearRoom- Supply60mpany'sswitchgearroomand/orspacefor meters.b) TransformerRooms- The numberandsizeof transformerroomsshallbe ascertainedfromthetotalpowerrequirementof theconsumer.c) Low-VoltageSwitchRoomS- The floor arearequirementin respectof low voltageswitchgearroomshallbeascertainedfromthenumberof feeders.d) Stand-byGenerators. A roomspacenot lessthan6.0mx 9.0mmaybe providedforhousinga stand-bygenerator.e) Location of SwitchRooms- In larg~installationsotherthanwherea substationisprovided,a separateswitchroomshallbeprovided;this s,hallbe locatedascloselyaspossibleto the electricalload centreand suitableductsshallbe laid with minimumnumberof bendsfrom the point of entryof the supplyto the positionof the mainswitchgear.The switchroom shallalsobeplacedin sucha positionthatrising ductsmay readilybe providedtherefromto theupperfloors of thebuildingin onestraightverticalrun~In largerbuildings,morethanonerisingductandhorizontalductsmayalsobe requiredfor runningcablefrom theswitchroomto thefoot of eachrising main.Suchcableductsshallbereservedfor .theelectricalservicesonlywhichmay,however,include mediumand low voltageinstallation,such as call-bell system,s;telephoneinstallationsshouldbesuitablysegregated.2.2.5 Location and Requirementsof Distribution Boards(1) The electricalcontrolgeardistributionboardsandotherapparatus,whicharerequiredoneachfloor mayconvenientlybemouutedadjacenttotherisingmains,andadequatespaceshouldbeprovidedateachfloor for thispurpose.2.2.6 Location and Requirementsof PBXlPABX Rooms(1) Informationregardingprovjsionfor andlocationofPBXlPABX shallbeobtainedfromtherelevantauthorityandadequatespaceshouldbeprovidedfor installationof t!teboards.24 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 2: GENERAL REQUIREMENTS2.3 PLANNING AND DESIGNING2.3.1General(1)Thedesignandplanningof anelectricalinstallationshalltakeintoaccountall theprevailingconditionswhichmayincludesome.orall of thefollowing:a) Typeof supply.b) Envisagedloadhavingregardto therequirementsof theowneror occupant.c) Theprobablemodificationsandfutureextensions.d) Thedegreeof electricalandmechanicalprotectionnecessary.e) Theprobableoperationandmaintenancecosttakingintoaccounttheelectricitysupplytariffsavailable.) Therelativecostof variousalternativemethods.g) Theneedfor radioandtelecommunicationinterferenceabatement.2.3.2LayoutandInstallationDrawing(1)Theelectricallayoutshouldbe consideredafterproperlocationsof all outletsfor lamps,fans,appliances- bothfixedandtransportable,motors,etc,havebeenselectedandbestmethodsofwiringdetermined.(2)All runsof wiring andexactpositionsof all pointsof switch-boxesandotheroutletsshallbefirstmarkedontheplansof thebuildingandapprovedbytheengineerin chargeortheownerbeforetheactualcommencementof thework.2.3.3Design(1)Thedesignof electricalinstallationshallensure:a) theprotectionof persons,livestockandproperty;b) theproperfunctioningof theelectricalinstallationfor the intendeduse.(2)Theinformationrequiredasa basisfor designshallbe:a) natureof current:a.c.and/ord.c.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 2ELECTRICAL INSTALLATION OF BUILDtNGSb) natureandnumberof conductors:i) fora.c.:- phaseconductor(s);- neutralconductor;- protectiveconductor.ii) ford.c.:- conductorsequivalentto'thoselistedabove.c) voltageandvoltagetolerances;d) frequencyandfrequencytolerance;e) maximumcurrentallowable;f) prospectiveshort-circuitcurrent;g) natureof demand;h) emergencysupplyor supplies;i) environmentalconditions.(3)Thedesignshallcomplywiththerequirementsof thisCode.2.4 MARKING OF EQUIPMENT2.4.1 General(1)Eachpieceof electricalequipmentshallbearsuchof thefollowingmarkingsasmaybenecessaryto identifytheequipmentandensurethatit issuitablefortheparticularinstallation:a) Themaker'sname,trademark,orotherrecognizedsymbolof identification.b) Cataloguenumberortype.c) Voltage.d) Ratedloadamperes.e) Watts,volt-amperes,orhorsepower.f) Whetherfora.c.,d.c.,or both.g) Numberof phases.h) FrequencyinHertz.i) Ratedloadspeedinrevolutionperminute.D Designationof terminals.k) Whetherforcontinuousor intermittentduty.1) Evidenceof approval.m) Suchothermarkingasmaybenecessarytoensuresafeandproperoperation.26 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD'SECTION 2: GENERAL REQUIREMENTS(2)Eachservicebox,atthetimeof installation,shallbemarkedin a conspicuous,legible,andpennanentmannerto indicateclearlythemaximumratingof theovercurrentdevicewhichmaybeusedfor thisinstallation.(3)At eachdistributionpoint,circuitbreakers,fuses,andswitchesshallbe marked,adjacentthereto,in aconspicuousandlegiblemannerto indicateclearly:a) whichinstallationor portionof installationtheyprotector control;b) themaximumratingof overcurrentdevicethatis permitted.2.4.2WorkmanshipandMaterials(1)Carefulattentionshallbepaidto them~chanicalexecutionof thework in connectionwithanyelectricalinstallation.(2)Anyinsta1!ationthathasbeenbadlyarrangedor poorlyexecuted,eithergenerallyor in anyparticularway,will notbeacceptedby theAuthorityhavingjurisdjction.2.4.3Materialfor Anchoringto MasonryandConcrete(1)Woodor othersimilarmaterialsshallnotbeusedasananchorintomasonryor concreteforthesupportof anyelectricalequipment.2.4.4Protectionof PersonsandProperty(1)Electricalequipmentshallbe installedandguardedso thatadequateprovisionis madeforthesafetyof personsand propertyand for the protectionof the electricalequipmentfrommechanicalor otherinjury to which it is liableto beexposed.2.4.5Maintainability(1)An assessmentshallbe madeof thefrequencyandqualityof maintenancethe installationcanreasonablybeexpectedto receiveduringits intendedlife.(2)Whereanauthorityis to beresponsiblefor theoperationof the installation,thatauthorityshallbeconsulted.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 27ELECTRICAL INSTALLATION OF BUILDINGS(3) The following characteristicsareto betakenintoaccountin applyingtherequirementsofthisCode, havingregardto thefrequencyandqualityof maintenanceexpected:a) Any periodicinspectionandtestingandmaintenanceandrepairslikely to benecessaryduringtheintended.life canbereadilyandsafelycarriedout.b) The effectivenessof the protectivemeasuresfor safetyduring the intendedlife ISensured.c) The reliabilityof equipmentfot properfunctioningof theinstallationis appropriatetothe intendedlife.2.4.6 Enclosures(1) Degreeof protectionprovidedby enclosuresfor ~lectricalequipmentshallbe in accordancewith mc 529.28 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD3.1 SCOPE3.2 NORMATIVE REFERENCES(a)BS 8206:1985 Part 1- Lightingfor Building.EBCS-10 1995 29(c)DIN 5035:1990 Part 2 - Artificial Lighting, RecommendedValues for LightingParametersfor IndoorandOutdoorWorkplaces.(b) DIN 5035:1990 Part 1- Artificial Lighting,TerminologyandGeneralRequirements.LJ..JUMINA TIONSECTION 3(d)DIN 5035:1988 Part~- Artificial Lightingof Interiors,HospitalLighting.(e)DIN 5035:1983 Part4- Artificial Lightingof Interiors,SpecialRecommendationsforLightingEducationalestablishments(t) DIN 5035:1987 Part 5 - Artificial Lightingof Interiors,EmergencyLighting.(g)DIN 5035:1988 Part7- Artificial LightingofInteriors,Lightingof RoomswithVDUWorkstationor VDU AssistedWorkplaces.(I) ThisSectionof theCode givesguidanceon designand installationof artificial lightingsystemsin interio.rs;it alsoappliesto artificiallightingof outdoorareas.(l) Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardsonElectricalInstallationof Buildings.ETHIOPIANBUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS3.3 DEFINITIONS.(1) For thepurposeof thisSectionof theCode,thefollowingdefinitionsshallapplyin additionto thetermsdefinedin Section1.meanilluminance(E)ratedilluminance(E,)lightlossfactor(V)depreciationfactor(P)reflectance(Pc)generallightinglocalizedlightinglocallighting30 EBCS-10 1995thearithmeticalmeanof the illuminancein a roomor in a roomzonebeingdefinedasthatareaof a roomin whichthesametypeof activityis performedat a numberof work-placesor which isusedfor similarpurposes.the nominal value of the mean illuminancethat the lightinginstallationis{fesignedto illuminate.the ratioof the ratedilluminance,En' to the designvalueof themeanilluminanceof a lightingsystem.thereciprocalof thelight lossfactor.the ratio of the luminousflux reflectedfrom a surfaceto theluminousflux incidenton it.the required averageilluminancewith a certain degree ofuniformity over the total area; and is obtainedby a regulararrangementof luminariesovertheceilingarea(seeFigure3.1).a non-uniform illuminanceover the whole work area (seeFigure3.2).lightingfor individualworkplaceinadditiontothegenerallightingproducedby placing luminariesclose to the visual task andsupplementedby a generallighting(seeFigure 3.1).ETHIOPIAN BUILDING CODE STANDARDAB1 1/ V I II I b)awitched;. a) groupedEBCS-10 1995 31SECTION 3: ILLUMINATIONFigure3.2LocalizedLighting' I I I / 1/ V // /I Figure3.1 GenerallightingFigure3.3 Locallighting- - . - :-;-.-./ 1 1 / 11/ / / / ---.----.-----.-.- - --------~~-._ .._---_ ..---.-ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSglareNote:directglarea conditionin whichvision is affectedby anexcessiveluminanceand/orexcessivedifferencesin luminancein thevisualfield (i.e;partsof this field areexcessivelybright).A distinctionis madebetween:disabilityglare,defmedasglarecausinganactualphysiologicalreductionin visualcapability(impaired, perceptionof contrastsand forms),anddiscomfortglare,definedasglareconsideredsolelyin termsof its psychologicaleffecton theoccupant.Discomfortglareexperiencedby theoccupantof a roomincreaseswithtimeandleadstoprematurefatigueandareductionin performance,performanceattitude,and well-being.a glarecauseddirectlyby luminancefromluminariesof luminousceilings.reflectedglare glareandcontrastreductioncausedby reflectionof highluminancefromglossysurfaces.Note: The maindisturbancescausedbysuchreflectionarecontrastreduction,andimpairedaccommodationand fusion.colour appearance thechromaticityof anilIuminantandis generallyexpressedasthecolourimpressionreceivedwhenlookingata light source.Note: The colour of the light emittedby a near-whitesourcescan be indicatedby its correlatedcolourtemperature(CCT). EachlamptypehasaspecificCCT; butforpracticaluse,theyhavebeengroupedinto threeclasses(seeTable 3.1).Table3.1: CorrelatedcolourtemperatureclassesCorrelatedcolour temperatureCCT CI18S-(CCT) H.CCT SECTION 3: ILLUMINATIONc%ur rendering therelationshipbetweentheoriginalcolourof an objectandthecolourin whichit is renderedby artificiallighting.Note: Theabilityof lightsourcetorendercoloursof s~aceaccuratelycanbeconvenientlyquantifiedby'theCIE generalcolourrenderingindex.Thisindexisbasedontheaccuracywithwhichasetoftestcolour'arereproducedbythelampt ofinterestrelativetohowtheyarereproducedbyan appropriatestandardlightsource,identicalagreementbeinggivena valueof tOO.Ou. EachlamptypehasaspecificCIE generalcolourrenderingindex;butforpracticalusetheycanbedividedintoanumberof groups(seeTable3.2)Whereveraccurate colour matching is required;e.g. colour printing inspection.Wherevercolour renderingis 01littlesignificancebut marked distortion01colour is acceptable.Wherevermoderatecoiour rendering Is required.TypicalapplicationWherevercolour rendering Is01no Importanceatall and.markeddistortion01colour is acceptable.Wherever accurate colour judgements arenecessary and/or good colour rendering Is, essential to appearance; e.g. shops and othercommercial premises.'Table3.2 Colourrenderinggroups60< R~9040< R. ELECTRICAL INSTALLATION OF BUILDINGSescapelightingsll/ety/iglltinglorpartial/Ju hazardousWOI'kplacua specified minimum illuminance foremergencyescapepurposes,thus,permittingbuildingsandplantto besafelyevacuatedatanytimeduringtheirutilization.safetylightingdesignedtoensurethattheworkperformedat suchworkplacescanbe safelyterminatedin the mannerrequiredand theworkplacesthemselvesevacuated'withoutdanger.Note: Particularhazardousworkplacesarethosewhichrepresentanimmediateriskof accidentor apotentialsourceof dangerto third partiesif thesupplyto the 'lightingshouldfail, raisedplatfonns,theatrestages,race-coursesandarenascountingasparticularlyhazardousworkplaces.standbylightingresponsetime.ratedduration01operationUmitduration01operatiOnan emergencylightingwhichcanassumethe functionofnormalartificiallightingfora limitedperiodsoasto enablenormalactivitiestocontinue.the intervalbetweena failurein thepowersupplyto,thenormalartificiallightingandtheprovisionof therequiredilluminancebytheemergencylighting.theperiodof timeforwhichanemergencylightingsystemisdesignedtooperate.theminimumperiodof timeduringwhichan emergencylightingsystemshallstillbecapableofachievingtheminimumilluminancespecifiedforthegivenapplication.Note: This conceptappliesspecificallyto battery-operatedsystems.lI$efullife thedurationof anemergencylightingsystemfromthedateofits commissioningupto thepointin timeat whichit onlyachievesthelimitdurationof operation.safetyluminaries,34 EBCS-10 1995a luminarywhichmayormaynotbeprovidedwitll itsownpowersupplyandwhichis usedfor safetylighting.ETHIOPIAN BUILDING CODE STANDARD3.4.2 Luminance3.4.1 D1umin~nce3.4 LIGHTINGREQUIREMENTSSECTION 3: ILLUMINATIONamouldedluminairebearingagraphicalsymbolto serveasanescapesign;it indicatesandassistthe ide~tificationof.escaperoute.a luminarywhichmayor maynotbe providedwith its ownpowersupplyandwhichis usedfor standbylighting.escapesign luminariesstandbylightingluminaries(2)For indoorworkplacesthataremannedfull-time,a minimu~ratedilluminanceof 200.01xshallbeprovidedunlessotherfactors(suchasnatureof operation,physiologicalreasons)require vdifferentvalues.(b) If tasksareperformedat fixed-locationworkplacesoutdoorsthatcorrespondto tasksperformedindoors(e.g.operationof wood-workmachines),thena ratedilluminancespecifiedfor suchtasksin Table3.5 for indoorworkplacesshallbeprovided.(1)Recommendedilluminancefor differenttypesof interiors,tasksandworkspacesgiveninTable3.5 andTable 3.6 shallbe takenastherecommendedminimumvalueson which thedesignandassessmentof lightinginstall~ionsareto bebased.(3)(it) In interiorsdesignedfor permanenthumanoccupation,aminimumratedilluminanceof100.01xis required.(1) Reflectancein theworkingzoneshallbeplannedsothattheratiobetweentaskluminance(innerfield) andthatof thesurroundingof thetaskareno greaterthanapproximately3:1./ (4)At no stagesin theuseful life of the lightinginstallationshall themeanilluminance,E,obtainedattheworkplacesbelessthan0.8 timesthevalueofthe ratedilluminance;atno singleworkplaceshall illuminanceeverfall to lessthan0.6timestheratedilluminance.(2)Reflectanceof from 0.2 to 0.5 arerecommendedfor workingsurfacessuchasbenchand,. -------------dt?,sktops.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 35ELECTRICAL INSTALLATION OF BUILDINGS3.4.3 Glare(1) Glare shall notbe causedby lamps0/ luminaries(directglare)nor by reflectionof highluminancefrom glossysurface(reflectedglare).(2) Lampswith a high luminance(e.g.filamentlampsandhighdischargelamps)shallalwaysbe shielded.I(3) In caseof luminariesfor local workplaceslighting,a directview of the lampsshall beprecludedby shieldingor by arrangingthemin a suitableposition.3.4.4 LightDirectionandModelling(1) Lighting shallbe directedto producean adequatedegreeof modellingshadowto enableobjectsandsurfacetextureto beeasilyrecognized.(2) Undulyhardshadowsshallbe,avoide,d.If theratio Ez(cylindrical):En(horizontal)atahightof I.20m abovefloor is not smallerthan0.3,undulyhardshadowscanbeavoid~d.(3) Deepshadowsproducingexcessive.luminancecontrastsshallbeavoided.3.4.5 ColourRendering(1) For inspectionandcomparisonof colours,theCIE generalcolourrenderingindex~ shallnot exceed90 andtheratedilluminanceshallbe IOOO.O/x.(2) Only lampsmeetingtherequirementsof ColourRenderingGroup3 (or higher)shallbeusedfor lightinginteriors.(3) Safetycoloursshall beduly recognizableassuch.36 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 3: ILLUMINATION3.5 EMERGENCY LIGHTING REQUIREMENTS3.5.1 EscapeLighting3.5.1.1 Illuminance(1)Theminimumilluminanceof the safetylightingfor escaperoutesshall be 1.0/x. Thisrequirementappliesto thecentreline of anescaperoutealonga horizontalplaneO.2mabovefloorlevel.(2)Theresponsetimeshallnotexceeda maximumof I5.0sec.(3)Therateddurationof operationshallatleastequalto thetimethatwill bespecifiedbysafetYlawtobeenactedby theconcernedgovernmentbody.(4)Thelimitdurationof operationshallbe% (for l.Ohr)or % (for3.0hr)of theratedduration.(5)Safetyluminariesfor escaperoutesshallbesitedaccordingto their luminancedistributionsoastomeettherequirementsspecifiedfor safetylightingandin sucha waythattheycannoteasilyberenderedineffective.(Principallocationsfor thesittingof safetyluminariesare,thus,neartheexitsof escaperoutesandatpoil}tswhereit is necessaryto emphasizethepositionsofpotentialhazards.)3.5.2 SafetyLightingfor ParticularHazardousWorkplaces3.5.2.1 I/Iuminance(I) Theminimumilluminancefor suchworkplacesshallbeO.1En(ratedilluminancespecifiedforthetaskandroomof suchworkplacesin Table3.5)butnot lessthan IS.O/x.(2)Theminimumilluminancefor platformandtheatrestagesshallbe 3.0/x, and I5.0/x forarenasandrace-courses.3.5.2.2 Colourrendering(1) Thecolour renderingshallat leastbe equivalentto Group3 so as to ensurethatsafetycoloursremainrecognizableassuch.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 37ELECTRICAL INSTALLATION OF BUILDINGS3.5.2.3 Responsetime(1) The responsetimeof safetylightingshallnotexceedamaximumof 6.5s.(2) In caseof raisedplatform,theatrestages,arenasandrace-courses,themaximumresponsetimeshallbe 1.0s.3.5.2.4 Rateddurationof operation(1) For workplaces,the lightingshallbe effectivefor as long as thehazardsubsists,with aminimumdurationof 1.0min.(2) For raisedplatform,theatrestages,race-coursesandarenas,therateddurationof operationshallat leastbeequalto thedurationrequiredby law.3.5.2.5 Sitingof safetyluminariesin hazardousworkspaces(1) Safetyluminariesshallbesitedsoastoensurethattherequiredilluminanceisprovidedovertheentireareain whichhazardoustasksarecarriedout.3.5.3 StandbyLighting(1) The requirementsto bemetby standbylightingareanalogousto thoseapplyingfor normalartificiallighting. To enablenormalactivitiesto continue,a minimumilluminanceof 10%oftheratedilluminancevalueis generallyrequired.3.6 LIGHTING REQUJ:.REMENTS FOR VARIOUS TYPES OF BUILDINGS3.6.1 General(1) The designobjectivesfor lighting shall be to provideboth good task visibility and asatisfactoryvisualenvironment.(2) (a) The lightingof workspacesshallensuregoodvisibilityof thevisualobjects.(b) The lightingof workplacesshallalsobeconduciveto concentrationandperformanceattitudes,counteractprematurefatigueandpermitanypotentialhazardsto be clearlyrecognized.38 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 3: ILLUMINATION3.6.2 IndustrialBuildings(I) In additiontothelightingrequiredfor specifictasks,ageneralilluminationshallbeprovidedtoallowsafemovementthroughthebuildingatall materialtimes.(2)Wherecriticalcolourmatchingis to bedonefor a longperiod,a minimumilluminanceofIOOO.Olx shallbeprovided.3.6.3 Offices(I) As indicatedon ratedilluminancetables,for generalofficesilluminanceof 500.01xandfordrawingofficesilluminanceof 750.01xshallbeprovided.(2)WhereVDU (VisualDisplayUnits)areused,theilluminanceshallberestrictedto 500.01xor lessto minimize the high brightnessreflectionfrom the screenand large luminancedifferencesbetweenscreen,any sourcedocumentsandthebackgroundsagainstwhich theseitemsareseen.(3)Wherelocalizedlightingis used,theratioof illuminancebetweenadjacentareasshallnotbemorethan3:1with a minimumilluminancefor lUtycontinuouslyoccupiedareaof 200.0/x.(4)Wherelocallightingjs used,theratioof illuminancebetweentaskareaandthesurroundingareashallnotexceed3:1.(5)A glarelimitingindexof 19 is appropriatefor generaloffice roomsandan indexof 16isdesirablefor drawingofficesbecauseof themoredemandingnatureof work.(6)Wheredaylightmakesa substantialcontribution,lampswith a CCT of 4000.0kor aboveshouldbeused.3.6.4HotelsandRestaurants(1)Indinningroomsandrestaurantsanilluminanceof 100.0lx isrecommendedonadinningtable.(2)In loungeandpublicbars,anaverageilluminanceof 50.0/x is recommended.(3)In kitchens.andotherserviceareas,a generalilluminanceof 300.0/x is recommendedandworkingareasshouldhavean illuminanceof 500.01x.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 39ELECTRICAL INSTALLATION OF BUILDINGS(4) Escapelightingshallbeprovidedfor publicrooms,staircasesandcorridorsandprovisionsshallbemadefor emergencylightingandexitsigns.3.6.5 EducationalEstablishments(1) The wide rangeof activitiescarriedout in teachingand'thevarietyof workingmediausedcreateconstantchangesin visualtasks;dueto this,specialrequirements,overandabovethosegiven in Clause3.4.1, shall applyto the qualityof the lightingin teachingrooms. Thisrequirementsaregivenin thefollowingClauses.(2) Theguidelinevaluesfor illuminance,colourappearance,colourrenderinggroupandqualityof classof directglarerestrictiongivenin Table3.7shallbeappliedin teachingspaces.(3) Shouldtherelevanttypeof roomor activitynotbe listedin Table3.7,thevaluesgivenfora similar,comparableroomor activityshallbeusedmutatismutandis.(4) TheguidelinevaluesgiveninTables3.5and3.6 for workspacesshallappJyto roomswhichhavethesamevisualrequirementsascomparableworkplaces,aswell asto generalpurposeandoffice-typerooms.(5) The mainchalkboardin teachingroomsand demonstrationdesksin teachingroomsforspecialsubjectsshallbeequippedwitha supplementarylightingsystemto increasetheverticalilluminance.3.6.6 Hospitals(1) Theguidelinevaluesfor hospitallightingsetin Table3.8shallapplyto all roomsandzonesof a hospital.(2) The lightingof beddedareasshallbeconduciveto thewell-beingof thepatient,while also~nablingexaminationor treatmentto becarriedout. To achievethesegoals:a) (i) thegenerallightingilluminanceshallbe IOO.Olx andshallnotdazzlethepatientsornursingstaff.(ii) the meanluminanceas perceivedby the recumbentpatientsshall be limitedtoIOOO.Ocdlm2while theluminanceof theceilingshallnowhereexceed500.0cdlm240 EBCS-10 1995 ETHIOPIAN B~ILDING CODE STANDARDSECTION 3: ILLUMINATION(ii) At no pointalongtheaxisin (i) aboveshalltheilluminancebe lessthan ISO.Olx.(ii) In wardsoccupiedby infants,a ratedilluminanceof 20.0lx is recommended.EBCS-10 1995 41d) (i) Nightwatchlightingwith illuminanceof approximatelyS.Olx shallbeprovidedforkeepingpatientsunderobservationduringthenight..(iii) The uniformityratioof illuminanceEmin:Eishallherenotbe lessthan1:2.c) (i) For the examinationandtreatmen~of patientsat.thebedside,a ratedhorizontalilluminanceof 300.Olx,inclusiveof thegenerallighting,shallbe providedO.ISmabovethelongitudinalaxisof theplaneof thebedsurface.b) (i) Eachbedshallbeequippedwith a rigidly mounted,adjustableluminaire.A ratedilluminanceof 300.0lx shallbeachievedonthereadingplane(seeFigure3.4).(ii) To avoidglarein multi-bedwards,theluminanceof readingluminariesin thefieldof visionof otherpatientsshallnotexceedIOOO.Ocd/m2(b) In additionto the generallighting an illuminanceof at least IOOO.Olx is generally 'requiredatthesiteof examination.(b)In viewof the illuminancesof 20,OOOlx to IOO,OOO.Olx requiredin theoperatingfield,the surroundinglightingshall be designedto reducethe adaptationproblemswhichwouldbecausedbyextremedifferencein theluminancebetweenoperatingfieldandthesurroundingarea.(c) The illuminanceof thesurroundinglight shallnotbe lessthan IOOO.Olx at a heightofI.Omabovefloor level.(5)(a)Standbylightingsystemshallbeprovidedfor theoperatingtheatres,anaestheticrooms,sterilizingsinksandrecoveryrooms.(3)(a)Generallightingwith a ratedilluminanceof 500.0lx and Group I colour renderingpropertiesshallbeprovidedfor examinationandtreatment.(4) (a)The lighting in operatingtheatreshall alwaysbe designedin conjunctionwith thelightingof theoperatingtheatrefield.ETHIOPIANBUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(b) The standbylightingof the-operatingtableshouldbeequalin all respectsto thenormallighting of this area,and shouldbe of the maintainedtype to ensurecontinuousillumination.800Figure 3.4 Referenceplansof a hospitalbedReading planeExaminationplanePlane'a;-'be~lurf.lcelC>C>0' ::gl lG....9003.7 OUTDOOR LIGHTING REQUIREMENTS3.7.1 Illuminance(1) For outdoorworkspaces,circulationareas/zonesandwork roads,therecommendedratedilluminancesin Table 3.6 shall be providedandthey areto be takenas the recommendedminimumvalues.(2) If the type of applicationof interestto the user is not listed,the recommendedvaluesspecifiedfor a similarspaceshallbeappliedanalogously.3.7.2 Colour RenderingGroup(1) At fixed locationworkspaces,the colour renderingcapabilityshall at.least meettherequirementsof Group3t; safetycoloursandcoloursusedfor classificationpurposesshallberecognizableassuch.tDataonthegrouptowhichlampsbelongwithrespectto theircolourrenderingcapabilityaregiveninproductlistsof manufacturers.42 EBCS-1 0 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 3: ILLUMINATION3.7.3Limitationof Glare(1)Limitationof directglareshallbebasedon Clause3.4.3of thisSection.(2)If theoutdoorworkplaceis floodlight,theluminariesusedshallbeso locatedandarrangedthathazardsdueto directglareareprecluded.3.7.4Lightingof OutdoorFixedLocationWorkspaces(I) If-tasksareperformedat fixed locationwork spacesoutdoorsthatcorrespondto tasksperformedindoor,then,local workplacelightingsshall be providedwith ratedilluminanceequivalentto thevaluesspecifiedfor suchtasksin Table3.5.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 43.J:>..J:>.I1c i;~': G VI rTable3.3 Typicalcharacteristicsof lightingsourcesusedfor generallightingCharacteristicsRange of luminousefficacy (1.0 Irn/W)Available wattage rangerN>Range of nominal life(h)Colour rendering groupNeed for control gearOperating positionRun-up time (min)Restrike time (min)CCT(K)TungstenFilament8 to 1825 to 15001000to 20001ANoAnyImmediateImmediate25000 to 3000Tungstenhalogen18 to24100 to 20002000 to 40001ANoHorizontalImmediateImmediate28ooot03100Low-pressuresodium100 to 17510 to 2006000 to 12000Non existentYesHorizontal6 to123Not applicableHigh-pressuresodium65 to 12050 to 10006000 to 120002 or 4depending onlamp pressureYesAny4 to72200Hot cathodetul;lularfluorescent35to 904 to 1255000 to 10000YesAnyImmediateImmediate2700 to 6500Cold cathodetubularfluorescent40 to6020W/mto30W/m20000Yes. AnyImmediateImmediate2700 to 6500High-pressuremercuryfluorescent35 to5550 to 20005000 to 100003YesAny4104000Mercury halide65 to 85250 to 100005000 to 10000Can very widelydepending on additivesused. Manufacturersshould be consulted.YesSome restrictien5103600 to 4400Note: Detailed informationabout any specific lamp type should be obtained from the manufacturer.~VI'Table3.4 Tubularfluorescentlampsapparentcolourandcolourrenderingcharacteristicsof lampsin generaluseLamp name Apparent colourColour renderingColour rendering characteristics(CCT class) group Typical applicationNorthlight colourCool1ASimilar to northsky light; emphasizes blues and,Used where colour rendering similar to north sky daylightmatching to less extent,greensis neededArtificial daylightCool1Asimilar to north light/colour matching but emitsUsed where critical colour matching complying withmore ultravioletto conform with natural sky lightBS 95:Part 1 is requiredSpecialIntermediate1AEqual emphasis given to all coloursUsed where fine colour judgements are required, e.g.hospitals, art galleries and museumsTriphosphor 4000Intermediate18Emphasizes oranges, greens and blue-violets,I Factories, offices and shops where good, but not critical,Isubdues yellows and deep reds[ colour rendering or matching is required together withhigh luminous efficacyTriphosphor 3000Warm18Emphasizes oranges,greens and blue-violets,Social areas, restaurants, hotels and homes where goodsubdues yellows and deep reds but fl0Table 3.5 Indoor workspacesrecommendedilluminance1 234 5 6Rated illuminanceColourClass ofColourType of Interior and/or task En. in Ixrenderingdirect glareRemarkIappearancegrouplimitationI1 General spaces1.1 Circulation zones in storerooms50ww,nw331.2 Warehousing1.2.1 Warehouses for goods of one kind or of large unit size50ww,nw33I1.2.2 Warehouses with goods of different kinds and search andretrievaltasks100ww,nw33!1.2.3 Warehouses with reading tasks 200ww,nw321.3 Automatic high-bay store,1.3.1 Aisles and gangways 20ww,nw33I 1.3.2 Control platform2002A1ww,nw1.4 Despatch room200ww,nw321.5 Rest rooms; sanitary facilities; medical roomsI1.5.1 Canteens200Iww,nw2A1Incandescent lamps may1.5.2 Other rooms for recreation and rest purposes100ww,nw2A1be used when lighting is1.5.3 Rooms for gymnastic exercises300ww,nw2A1to create a specific1.5.4 Changing rooms100ww,nw2A2atmosphere.1.5.5 Washrooms100ww,nw2A2Supplementary mirror1.5.6 Toilets100ww,nw2A2lighting1.5.7 Medical treatmentand nursing rooms; first-aid facilities500ww,nwlA1optionalI1.6 Building services installationsI1.6.1 Machine rooms100ww,nw331.6.2 Power supply and distribution L100ww,nw331.6.3 Telex and post rooms500ww,nw2A11.6.4 Telephone switchboard300ww,nw2A1- ~--'Table3.5 Indoorworkspacesrecommendedilluminance(conte'd)12345 6--Rated illuminance.ColourColourClass of directType of interiorand/ortask En. In!!renderingglare Remarkappearance 'limitationgroup2 Circulationareas in buildings II 50I 3I3 Adjustment of rated2,1 For persons ww,nw!2.2 For persons and vehicles100ww,nw33illuminance to2.3 Stairs; escalators, and ramps100ww,nw32adjoining spaces;2.4 Loading plattonns100ww,nw32En1~0.1En22.5 Automatic transport facilities or conveyor belts in'orwhere En1= En of theadjoining circulation areas100ww,nw33circulation areas.2.6 Shed entrances100ww,nw33En2= En of adjoiningspaces2.6.1 Day-time operation2 x Entww,nw Only luminariestEn of adjoiningmin 400.0~without luminousinterior.side panels areThe interior area ofto be used. the shed entrance is2.6.2 Night-time operation0,5 Entww,nw to be illuminated.to0,2 Entww,nw3-Only luminariestEn of the adjoiningwithout luminous interior.The interiorside panels arearea of the shedto be used. entrance is to beilluminated~00Table 3.5 Indoor workspacesrecommendedilluminance (conte'd)6Remark2I4 I 5 I-- I ----1Colour! .. 'I Class of directrendenn ...9 glare limitation I1_ group_ I __ II II II II 1 I Workplace-oriented general lighting;minimum of 0.8 En at workplace3ww,nwColourappearanceI2300Ratedilluminance Enin~--Type of interior and/or task3 Offices and similar rooms3.1 Offices with daylight-orientedworkplaces,all in immediate vicinity of windows3.2 Offices3.3 Open-plan offices with averagereflectance with high reflectance3.4 Technical drawing office5001000750ww,nwww,n',ww,nw2A22AHigh reflectance: ceiling: 0.7minimum, walls/partitions: 0.5minimum, local workplace lightingpermitted3.53.63.73.8Conference and consultation roomsReception roomsRooms open to the publicData processing rooms ~300100200500ww,nwww,nwV'IW,nwww,nw2A2,2A2AEn referred to working plane ofdrawing board of 75 to thehorizontal at the centre point of theboard and a height of 1.2m.~0Table3.5 Indoorworkspacesrecommendedilluminance(conte'd)12345 6- -RatedType of interiorand/or task illuminance, En>Colour appearanceColour renderingClass of direct glareRemarkin 2sgrouplimitationI4 Chemical industry4.1Remote controlled process engineering plants 50ww,nw33I4.2 Process engineering plants100ww,nw33,4.3 Permanently manned workplaces in process engineering plants200ww,nw334.4 Measuring stations, control platforms andobservations posts300ww,nw2A1Where required for operational reasons,4.5 Laboratories; pharmaceutical packag~ms 300ww,nw2AI2En may be less than 300.02s.4.6 Particular exacting visual tasks 500Iww,nw2A14.7 Colour matching 1000nwlA1Local workplace lighting recommended,Iwith shielding against light sources ofother light types.5 Cement Industry, glass works and pottery5.1 Workplaces or zones at furnaces/kilns, at rawmaterialsmixers, at grinning plant in brickworks200ww,nw335.2 Enamelling, rolling, pressing, moulding of simple parts; glazing; glass blowing300ww,nw325.3 Grinding, etching, glass polishing; precisionI ,moulding; manufacture of glass instruments500ww,nw3i15.4 Colouring and decorating500ww,nw2A15.5 Grinding lenses, crystal glassware; manual griding and engraving; medium quality tasks750ww,nw2A15.6 Precision work1000ww,nw,twI2A1Local workplace lighting recommendedv.o Table3.5 Indoorworkspacesrecommendedilluminance(conte'd)1 2345 6RatedColourColour renderingCliiss of directType of Interior and/or taskilluminance, En' RemarkIn !!appearancegroupglare limitation6 Smelting lIl(orks, Iron and stnl works, roilingmills, foundrl&!6.1 Production plants not requiring manualintervention50wvr,nw336.2 Production plants requiring occasional manual intervention100ww,nw336.3 Permanently manned workplaces in production plants200ww,nw32Where required for operational reasons,6.4 Measuring stations, control platform and ~V~ may be less than 3oo.0~observation posts300ww,nw2A16.5 Testing and inspection areas500ww,nw,tw2A1g, may exceed 5oo.01x7 Metal working and finishing 7.1 Hammer-forging of small parts200ww,nw327.2 Welding300ww,nw327.3 Machining centres; automatic or semiautomatic machining plant300ww,nw317.4 Rough and medium machining tasks, withpermissible deviations greater than 0.1mm300ww,nw317.5 Precision machining tasks, with permissible deviations less than 0.1mm500ww,nw317.6 Robot-ilquipped workplaces300ww,nw317.7 Laying out and control workplaces; measuring stations750ww,nw317.8 Cold rolling mills200ww,nw327.9 Wira and tube drawing works; manufacture of cold rolled sectional strip300ww,nw327.10 Machining and working of sheet metals300ww,nw327.11 Manufacture of hand tools and cutlery500ww,nw31Table3.5 Indoorworkspacesrecommendedilluminance(conte'd)1 2345 6RatedColourColourClass of direct glareType of Interior and/or tasklIIumlnance,E.,rendering grouplimitationRemarkIn Ixappearance7 Metal working and finishing (conte'd) 7.12 Assembly7.12.1 Low precision200ww,nw327.12.2 Medium precision300ww,nw317.12.3 High precision500ww,nw317.13 Drop forging200ww,nw32-7.14 Foundries 7.14.1Underfloor men-sized trenches, beltconveyor roads, cellars, etc.50ww,nw337.14.2 Platforms100ww,nw337.14.3 Sand preparation200ww,nw337.14.4 Dressing room300ww,nw327.14.5 Workplaces at cupola furnaces and mixers200ww,nw327.14.6 Casting bays300ww,nw327.14.7 Shake out bays200ww,nw327.14.8 Mechanical moulding200ww,nw327.14.9 Hand moulding300ww,nw327.14.10 Core moulding300ww,nw327.14.11 Patternmaking500ww,nw317.15 Die casting works300ww,nw327.16 Surface treatment 7.16.1 Electroplating300ww,nw,tw327.16.2 Priming, painting, varnishing500ww,nw,tw317.16.3 Inspection areas750ww,nw,tw2A17.17Tool, gauge jig manufacture; precisionmechanics; highprecision assembly1000ww,nw,tw31Local workplace lighting recommendedVlNTable3.5 Indoorworkspacesrecommendedilluminance(conte'd)1 2345 6RatedColourColourClass of direct glareType of Interior and/or taskilluminance,rendering RemarkappearancelimitationE',ln~group7 Metal working and finishing (conte'd) 7.18 Motor vehicle manufacture7.18.1 Shell manufacture500ww,nw,tw327.18.2 Body surface treatment500ww,nw,tw32Shielding against direct glare at7.18.3 Paint spray booth1000ww,nw,tw3-assembly lines with local workplace7.18.4 Paint polishing bays750ww,nw,tw31fluorescent lighting may be dispensed7.18.5 Retouching1000ww,nw,tw31with if the operational conditions so7.18.6 Upholstery500ww,nw,tw32require.7.18.7 Final vehicle assembly500ww,nw,tw327.18.8 Inspection750ww,nw,tw318 Power stations 8.1Loading plant 50ww,nw328.2 1i30ilerroom100ww,nw338.3 Pressure equalizing chamber in nuclear power stations200ww,nw2A18.4 Machine rooms100ww,nw328.5 Ancillary rooms, e.g. pump rooms, condenser rooms50ww,nw328.6 Switchboard plant100ww,nw2A28.7 Control rooms300ww,nw2A1Where required for operationalreasons, ~ may be less than 300.0~.8.8 Maintenance work on turbine and generator.500ww,nw2B2By providing supplementary lightingwhile work is carried out.9Electrical engineering Industry9.1Cable manufacture; varnishing and impregnationof coils; simple assembly tasks; winding of coilsand armatures with heavy-gauge wire300ww,nw311 2345 6RatedColour renderingClass of direct glareType of interiorand/or taskilluminance,Colour appearance RemarkEn' in Ixgrouplimitation9Electrical engineering Industry (conte'd) (9.2 Assembly of telephones and small motors;winding of coils and armatures with medium-gauge wire500ww,nw,tw319.3 Assembly of precision devices; radio andLocal workplace lightingtelevision sets; winding of fine wire coils;,ac:l;';'::.~3ndedfabrication of fuses; adjustment, testing and calibration1000ww,nw,tw319.4 Assembly of high-precision parts and of electroniccomponents1500ww,nw,tw2A110Jewellery Industry, watch and clock makingIndustry10.1 Manufacture of jewellery1000ww,nw,tw2A1Local workplace lighting10.2 Working of precious stones1500ww,nw,tw1B1recommended10.3 Optician's and watchmaker's workshops1500ww,nw,tw2A111Woodworking11.1 Steam pits100ww,nw3311.2 Saw mils200ww,nw3211.3 Bench work, gluing, assembly300ww,nw2A211.4 Selection and inspection of veneer wood; marquetry work500ww,nw1A111.5 Pattern making shop; polishing; varnishing 11.6Work at woodworking machines; turning,chamfering, dressing, rebating, slotting,cutting, sawing,sinking500ww,nw2A111.7 Surface finishing500ww,nw2A111.8 Checking for defects750nw,tw1A1Table3.5 Indoorworkspa~esrecommendedilluminance(conte'd)2I345 6----- --1------------ --RatedColourColourCia of dlutetType of Interior and/or 'akilluminance,render!ngglareRemarkEIlI Inj!appearancegrouplimitation----12 Paper Industry, printing and allied trades12.1 Work edHollanders, edge runners, grindingmills200ww,nw3312.2 Paper-making and corrugeding machines;cardboard fabricedion300ww,nw32AV6idance of reflected glare by12.3 Standard bookbinding; wallpaper printing300ww,nw2A1selection of correct light incidence; forhand composing, obliquely from the12.4 Trimming, gilding, embossing; work at printingside.presses500ww,nw2A112.5 Hand printing;paper sorting750ww,nw,tw',2A112.6 Retouching; lithography; hand and machinecomposing; make-ready1000ww,nw,tw2A1Local workplace lighting12.7 Colour control in multk:oIoured printing1500ww,nw,tw1A1recommended.12.8 Steel and copper engraving2000ww,nw,tw2A113Leather Industry13.1 Work edvl'.ds;tubs, pits200ww,nw33For tubs, due edtentionmust be givento vertical lighting, reflections beingavoided by means of suitable light13.2 Scraping, splitting, smoothing, fulling of hides300~I-ww,nw 2A1incidence.13.3Saddlery work; quilting; sewing polishing;sorting; pressing; cutting to size punching;shoe manufacture1-500 WW.OW2A11For dark materials, increase to-............... ----- ___ - OOO+OI}o(. lC)CaJ _ClIrk,?,I~~ ,lighting-Table3.5 Indoorworkspacesrecommendedilluminance(conte'd)Type of Interior and/or task13 Leather Industry (conte'd)-t--~-2rated illuminance,Em InJ!Colourappearance4Colour.renderinggroup5Class of directglarelimitation6RemarkVIVI13.4 Leather dyeing (mechanical)13.5 Quality control13.5.1 Medium standard13.5.2 High standard13.5.3Very high standard13.6 Colour matching14 Manufacture and processing of textiles14.1 Workplaces and work zones at baths and inbate breaking areas14.2 Combing, washing, ironing, devilling andcarding work; drawing, teasing, sizing, cardcutting; slubbing; jute and hemp spinning14.3 Dyeing14.4 Warping, beaming, spinning, spoiling andwinding, twisting, braiding, knitting, andweavingH.5 Comb pricking; perching; sewing; block printing14.6 Millinery14.7 Trimming; burling14.8 Goods inspection; colour matching14.9 Invisible mending750750.10001500100200300300500750750100010001500WW,nw,twnwnw,twnw,twtw,nwww,nwww,nwww,nwww,nwww,nwww,nw,twWW,nw,twww,nw,twnw,tw 1I2A1818181A332A2A2A2A2A1A2A1,11322For surface inspection tasks, providesupplementary lighting with obliqueincidence. Local workplace lightingrecommended.Shield from light sources with adifferent iIIuminant. Local workplacelighting recommended. --Local workplace lightingrecommended.For colour matchIng tasks, shieldfrom light sources with a differentilluminant.Table 3.5 Indoor workspacesrecommendediIIuminance(conte'd)1 2345 6Type of interiorand/or taskRated illuminance,Colour appearanceColour rendering'Class of direct glareRemarkEm in Ix grouplimitation15 Food and luxury food Industries 15.1Workplace and work zones in breweriesand malthouses; washing, tiling inbarrels, cleaning, sieving, peeling,cooking and boiling in canning andchocolate factories; workplaces andwork zones in sugar refineries. for dryingand fermenting leaf tobacco; fermentingcellar200ww,nw2A3.15.2Sorting and washing of produce;grinding, mixing. packaging300ww,nw2A2Depending on the layout of theworkplace, ensurE!adequate vertical15.3Workplaces and work zones in abattoirs, illuminance.butcher's stores. dairie:;, mills and filter beds300nw2A215.4Cutting and sorting of fruit andvegetables300nw2A115.5Making of delicatessen products;kitchens; cigar and cigarette manufacture500nw2A115.6Inspection of glass jars and productcontrol; garnishing, decorating, andsorting500nw2A115.7Colour matching; laboratories 1000ww,nw,tw1A1For colour matching, shield fromlight sources with a differenti1luminant.Local workplace lightingrecommended.1e Wholesale and retail trade16.1 Sales areas300ww,nw2A116_2 Cash desks500ww,nw2A1Table 3.5 Indoor workspacesrecommendedilluminance (conte'd)1 2345 6Type of interior and/or taskRated illuminance,ColourColourClass of directEm in Ixrendering groupglare limitationRemarkappearance17 Craft and trades (examples from differentbranches)17.1Removing rust and painting steel components 200ww,nw3217.2 Subassembly of heating and ventilation system200ww,nw3217.3 Locksmith and plumbing work300ww,nw3217.4 Motor car workshop300ww,nw3217.5 Carpentry and joineryww,nw3217.6 Repair shops for machines and appliances500ww,nw3117.7 Radio and television repair workshops500ww,nw2A118 Services enterprises 18.1Hotels and restaurants18.1.1 Reception200ww,nw2A118.1.2 Kitchen500ww,nw2A218.1.3 Dining rooms200ww1B-18.1.4 Conference rooms300ww,nw2A118.1.5 Self-service restaurants300ww,nw1B118.2 Laundries and dry cleaners 18.2.1 Washing300ww,nw2A218.2.2 Machine ironing300ww,nw2A118.2.3 Ironing by hand300ww,nw2A118.2.4 Sorting300ww,nw2A118.2.5 Stain removal inspection1000ww,nw2A118.3 Hairdressing500ww,nw,tw1A1Local workplace lighting permitted18.4 Beauty treatment750ww,nw,tw1A119 Plastics processing19.1Injection moulding 500ww,nw3219.2 Blowing300ww,nw3219.3 Compression moulding300Iww,nw 32Table3.6 Outdoorworkspaces.-123 4 5Type of outdoorworkspacecirculationareas/zonesandRatedUniformityofilluminance,Enilluminance,g,=Colour renderingRemarksworkshops in !!s..inlgroup1 Circulationareas on works premises,works roads 1.1 Gates500.5 3s. .shallbe 1.0~minimum.1.2 Footpaths5gi~O.08 4Sw s. ....andg2 relatedtothecentrelineof thepath..1.3 Cycle pathsSn~gi~0.34s. .and92relatetothecentrelineof thepath. -1.3.1 Worksroadswithloadingandunloadingzoneor with heavycross trafficanda speed limitof 30.0km/hor100.4 4less1.3.2Worksroadswithloadingandunloadingzoneor withheavycross trafficanda speedlimitof 50.0km/hor200.4 4less2 Parkingareas30.2 43 Harbours 3.1 Containertransshipmentareas3.1.1Openstorageareasandcirculationareas200.2 41)g~=E''/s.axTable3.6 Outdoorworkspaces(conte'd)1 23 4 5Type of outdoorworkspace,circulationa.reas/zones,andRatedUniformityofilluminance,illuminance,9! =E~Colour renderingRemarksworkshops g.' in IxIE.group3 Harbours (conte'd) 3.1.2Loadingand unloadingcontainers1000.24Supplementarylocalworkplacelighting3.2Quayage requiredin containers.3.2.1Quayside50.2 43.2.2Loadingunitloads20.0.2 43.2.3Loadingbulkgoods (drybulkandfluids)100.2 4Dazzlingof shippingto be avoided.3.3Workspaces in depotareas3.3.1Unitloads200.2 43.3.2Bulkgoods50.2 43.3.3Hazardousfluids50.2 43.4Wharfsfor passengertraffic 300.2 33.5Wharfsfor mixedtraffic 500.2I33.6Docks 500.2II43.7Repairfacilitiesin harbour 500.2 4I,4 Transshipmentareas, loadingareasi300.5 4III I5 Workspaces in depot areas, stacks iI II5.1 Piecegoods30I0.2!4I ,5.2 BulkgoodsI10 0.2i4I I!,iII6 Track systemI6.1 Sidings,shuntyardsI6.1.1Publictransport36.1.2Othertraffic56.2 Platforms III306.3 RehandlingyardsI6.4 Levelcrossing I20II0oTable3.6 Outdoorworkspaces(conte'd)1 23 4 5Types of outdoor workspace, Circulation areas/zones, andRatedUniformity ofilluminance, ENIlluminance,Colour renderingRemarksworkshops in Ix91 =Em~group7 Building sites,7.1 Overground workings200.2 47.2 Underground workings200.2 47.3 Structural steelwork, structural metalwork200.2 47.4 Tunnelling300.2 48 Large-scale chemical production plant100.2 49 Power stations 9.1Circulation areas9.1.1 Conventional fuel power stations100.2 49.1.2 Nuclear power stations200.2 49.2Switchboard plant 200.5 410 Open cast mining 10.1Directional lighting 3-410.2 Supplementary working zone lighting200.2 411 Sewage treatment works 11.1Paths and roads 50.2 411.2 Tanks and basins-- 4Lighting only where needed12 Filing stations1000.53Table3.7 Guidelinevaluesfor educationalestablishmentlighting1 234 5 6RatedColourColourQuality class ofTypes of space or activityilluminance, ~renderingdirect glareRemarksIn Ixappearanceproperty grouprestriction1 Outside structures 1.1 Roofed recreation area50ww,nw3-1.2 Roofed bicycle stands20ww,nw3- )2 Secondary rooms for special purposes2.1Room for teaching aids and collections 200ww,nw22If necessary, supplementary lighting for2.2 Projection200ww,nw22stacks cabinets3Community rooms3.1 Corridors100ww,nw233.2 Staircases100ww,nw223.3 Entrance halls100ww,nw233.4 Canteens200ww:nw213.5 exhibition rooms10Table3.7 Guidelinevaluesfor educationalestablishmentlighting(conte'd)Type of space or activity64 52 3ColourQualityclass ofRatedColourrenderingdirect glareI Remarksilluminance,Enappearancepropertyrestrictionin Ixgroup4 General,teachlngrooms The mainchalkboardand/ordemonstrationdesk requiresupplementarylighting.4.1 Roomsfor pre-schoolingpurposes4.2 Teachingrooms,ifnotincludedunder4.3below4.3 Teachingroomswitha day-lightfactor..Q (seeDIN5034Part1) lessthan1% atthemostunfavourableworkingposition,teachingroomsusedchieflyintheeveningor speciallyforadulteducation-1) Attheworkingpositions,a minimumofO.BS is required.2) TheTIluminancerequiredifthe roomisputto otheruses can be attainedbyswitchingpartsof the lightingsystem3) High reflectanceis deemedto be at least0.7forthe ceiling,at least0.5forthewallsor roomdividers.I1tl-- 1t lI 2 iI 2 II 1 I1 II 4) En withrespectofthe drawing-boardI 1 positionedas for useat75fromtheI 1 I horizontal,thecentreof the boardbeingJ. 1 : 7ata heightof 1.2m----.--+----- ---I I2222221222222IIIIII~._~IIww,nwww,nw_,nwww,nwww,nwww,nwww,nwww,nwww,nwww,nwww,nwww,nwww,nwww,nw5007507501000300300'50ciIIIII500 !500 I500 I500 I500500700 I- --1-- ---l-II6 Lecturetheatres6.1 Lecturetheatreswithwindows6.2 Lecturetheatreswithoutwindows5.1 Kitchensforteachingpurposes5.2 Roomsfor manualtraining5.3 Roomsfor handicrafts,sewing,typewriting5.4 Drawing,painting5.5 Physics,chemistryandbiology5.6 Laboratories,demonstrationrooms5.7 Technicaldrawing'4.4 Open-planteachingspaces- withhighreflectance'- withmediumreflectance5 Teaching roomsfor special purposest The valuesof the luminancerestrictioncurvebelongingto thenexthighestnominal illuminanceshall be observedTable3. 8 Guidancevaluefor hospitallighting----~If required, switchable orcontrollable to give lowerilluminance valuesIf required, switchable orcontrollable to give lowerilluminance valuesGeneral lighting at workp,lacesnot less than 160.0Ix+-~~--~~-=-----------I,II--+IiI1111111General lightingNight-watch lightingGeneral lightingAt site of examinationPreparation 500WW,nwUrology50ww,nwRectoscopy50ww,nwGynaecology50ww,nwGeneral lighting500ww,nwRefractometry50ww,nwSkiascopy50ww,nwOphthalmoscopy50ww,nwOphthalmometry50ww,nwPerimetry5ww,nwAdaptometry5ww,nwGeneral lighting500ww,nwWork at monitor20ww,nwi I I I IT I I of I Ratad I U h I colour I Qualityclass for I'IYIpelof alctvlty type I illuminance, 'I 91t ng renderinggro i restrictionof direct I RemarksI umnaton ... E I .. co our t 1 I I L='n ~ up i 9areI General lighting ---i--~--r~-ww --, 1 i 1 -----:I Reading lighting I 200 I ww I 1 I 1 ! Reduced glare for patientsExamination lighting I 300 : ww I 1 'I 1 I Approximately 5.0~Night watch lighting I ww : 1 1 INight lighting L I ww ! 1 r--- 1 II 200 I ww I' 1 I'I IL-- 20 I I 1 II I .: 500 I ww,nw 1 II >1000 I~ww,nw, 1 II i I---~---II I II I II 1 II ,, 1 I I1 !1 IRoom typeBedded areaGeneral examination andtreatment roomsFor endoscope examinationInfants wardSpecial examination andtreatment roomsFor ophthalmic examinationfor radiographic examinationTable3.8 Guidancevaluefor hospitallighting(conte'd)Type of activity / Type ofRatedUghtingcolourQuality class forRoom typeIlluminance,renderingrestriction of directRemarksIllumination s..in !!colourgroup1)glareSpecial examination andtreatment rooms (conte,d)for dental examinationsfor dermatological examinationsIntensive care areasOperating theatre suitesGeneral lighting1000nw1 1Illuminance: from 20000 toOperating field lighting-nw1 1100000.0Ix, 1ooo.01xSurround lighting in operating-nw1 1minimum; desiredtheatreilluminance: 2OOO.01xAncillary roomsGeneral lighting for changingroomsWash rooms500nwRooms for pre-surgery preparation500nwRooms for post-surgery treatment500nwInstrument stories500nw1 1Sterile parts stores500nwSterilization stores500nwRecovery room500nwRecovery lighting100ww,nw11Reduced glare for patientsTherapy roomsMedicinal bathsGeneral lighting300ww,nw11PhysiotherapyMassageDialysis roomsGeneral room lighting100WW1 1Reduced glare for patientsGeneral lighting in beddes areas500ww1 1Laboratories and dispensariesGeneral lighting500ww,nw11Workplace lighting, ifColour check1000tw1 1required.Table 3. 8 Guidance value for hospital lighting (conte'd)Type of activity / Type ofRatedLightingColourQuality class forRoom typeilluminance s..renderingrestriction of directRemarksillumination in...!!colourgroup'glare ---Corridors and stairsBedded areas- day-time200ww2 1- at night50ww2 1Operating theatre suit - day-time300nw2 1- at night100nw2 1~~--Toilets and dirty work areasSanitary blocks connecting to100ww1 -bedded areas-Toilets200ww2Dirty work areas300ww,nw2-Duty rooms for doctorsand nursingGeneral lighting300ww1 1If required, workplacestaffLighting for difficult visual tasks500ww1 1lighting for filling hypodermicsyringes, sorting medicinesetc.Post-mortemexamination roomsGeneral lighting1000nw1 1Workplace lighting>5000nw1 -IELECTICAL INSTALLATION OF BUILDINGSSECTION 4CONDUCTORS4.1 SCOPE1) This Sectionof theCodespecifiesthenominalcross-sectionalareasof conductorsin electriccablesandcordsusedfor lighting,applianceandpowersupplycircuitsfor anominalvoltagenot exceeding1.0kV.2) The conductorsincludesolidandstrandedcopperandaluminiumconductorsin cablesforfixed installationandflexiblecopperconductors.3) The provisionsof thisSectiondonotapplyto conductorsfor telecommunicationpurposes.4.2 NORMATIVE REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardson ElectricalInstallationof Buildings.(a) BS 767]:]992(b) BS 6360:]991(c) IEC 228:1976(d) IEC 50(46]):]984(e) IEC 364-5-523:199366 EBCS-1 0 1995Requirements for Electrical Installation, lEE WiringRegulationsSixteenthEdition.Specificationfor Conductorsin IsolatedCablesandCords.Conductorsof InsulatedCables.InternationalElectrotechnicalVocabulary.Electrica]Installationof Buildings.ETHIOPIAN BILDING CODE STANDARD(1) C22.1:19904.3 DEFINITIONSSECTION 4: CONDUCTORSCanadianElectricalCode,PartI, SafetyStandardfor ElectricalInstallations,SixteenthEdition.j(1) For thepurposeof thisSectionof theCode,thefollowingdefinitionsshallapplyin additionto thosetermsdefinedin Section1.conductor(of a cable)plain conductormetalcoatedconductorsolid conductorshapedconductorstrandedconductorflexible conductorconcentricconductorinsulation(of a cable)extrudedinsulationapartof acablewhichhasthespecificfunctionof carryingcurrent.a metalconductorin whichthewire or wiresarenot coatedwithanadditionalmetal.a conductorin whicheacnindividualwire is coveredwith a thinlayerof a differentmetalor metalalloy.aconductorconsistingof a singlewire.(A Solidconductormaybecircularor shapedotherwise.)a conductorthecross-sectionof whichis otherthancircular.aconductorconsistingof anumberof individualwires,all or someof whichgenerallyhavea helicalform. (The strandedconductormaybecircularor shapedotherwise.)a strandedconductorhavingwiresof diameterssmallenoughandso assembledthatthe conductoris suitablefor use in a flexiblecable.a conductorso constructedasto surroundoneor moreinsulatedconductors.insulatingmaterialsincorporatedin a cable with the specificfunctionof withstandingvoltage.insulationconsistinggenerallyof one layerof a thermoplasticorthermosettingmaterialandappliedby extrusionprocess.ETHIOPIAN' BUILDING CODE STANDARD EBCS-10 1995 67ELECTICAL INSTALLATION OF BUILDINGSmineralinsulation insulationconsistingof compressedmineralpowder.conductorscreen an electrical screenof non-metallicand/or metallic materialcovering~neconductor.insulatingscreen;corescreen anelectricalscreenof non-metallicmaterialcoveringtheinsulation.shield(of a cable) a surroundingearthedmetalliclayerto confinethe electricfieldwithinthecableand/ortoprotectthecablefromexternalelectricalinfluence. (Metallic sheaths,armours and earthedconcentricconductorsmayalsoserveasshields).core(insulatedconductor) anassemblycomprisinga conductorwith itsown insulation(andscreenif any).sheath(jacket) a uniformand continuouscircularcoveringof metallicor non-metallicmaterial,generallyextruded.oversheath anon-metallicsheathappliedoverametalliccovering,constitutingtheouter-mostsheathof thecable.armour a coveringconsistingof a metaltape(s)or wires,generallyusedtoprotectthecableformexternalmechanicaleffects.single-conductorcable;slng/e-cotecable a cablehavingonlyonecore.multiconductorcable a cablehavingmorethanonecore.multicorecable a.cablehavingmorethanonecore.flat (multicore)cable a multicorecablehavingcoresor groupsof coresarrangedinparallelflat formation.flexiblecable a cablewhich is requiredto be capableof beingflexedwhile inserviceandof whichthestructureandmaterialsaresuchasto fulfilthis requirement.68 EBCS-1 0 1995 ETHIOPIAN BILDING CODE STANDARDcordaerial (insulated)cableheatingcableSECTION 4: CONDUCTORSa flexiblecablewitha limitednumberof conductorsof ~mallcross-sectionalarea.aninsulatedcabledesignedtobesuspendedoverheadandoutdoors.a cablewith or withouta shieldor a metallicsheath,intendedtogiveoff heatfor heatingpurposes.4.4 SIZE OF CONDUCTORS4.4.1 PhaseConductorsin a.c.CircuitsandLiveConductorsin decircuits(1) The minimumnominalcross-sectionalareaof conductorshallbe:a) .1.0mm2for cablesandinsulatedcopperconductorsfor powerandlightingcircuits;b) 10.0mm2for barecopperconductorsfor powercircuits;c) 16.0mm2fo~barealuminiumconductorsfor powercircuits;..d) O.5mm2for flexiblecablesof copperconductorsfor extralow voltage.4.4.2 NeutralConducton ~,.l(1) For a polyphasecircuits in which imbalancemay occur in normalservice,the neutralconductorshall havea cross-sectionalareaadequateto carry the maximumconnectedloadbetweentheneutralandanyoneungroundedconductor.(2) For a polyphasecircuitin whichseriousimbalanceis unlikelyto occurin normalservice,otherthanadischargelightingcircuit,multicorecablesincorporatingareducedneutralconductormaybeused.Whensingle-corecablesareusedin suchcircuits,theneutralconductorshallhaveacross-sectionalareaappropriateto theexpectedvalueof theneutralcurrent.(3) In a dischargelightingcircuit,theneutralconductorsshallhavea cross-sectionalareanot.lessthanthatof thephaseconductor(s).ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 69ELECTICAL INSTALLATION OF BUILDINGS4.5 AMPACITY OF WIRES, CABLES AND FLEXIBLE CORDS4.5.1 ConductorOperatingTemperature(1) The currentto becarriedby anyconductorfor sustainedperiodsduringnormaloperationshall be suchthatconductoroperatingtemperaturegivenin theappropriatetableof current-carryingcapacityin AnnexB of thisSectionis notexceeded.4.5.2 CablesConnectedin Parallel(1) Exceptfor a ringfinal circuit,cablesconnectedin parallelshallbeof thesameconstruction,of cross-sectionalarea,lengthanddisposition,withoutbranchcircuitsandarrangedso as tocarrysubstantiallyequalcurrent.4.5.3 CablesConnectedto BareConductorsor Busbars(1) Wherea cableis to beconnectedto a bareconductorbusbar,its typeof insulationand/orsheathshallbesuitablefor themaximumoperatingtemperatureof thebareconductoror busbar.4.5.4 VoltageDrop(1) The sizeof conductorsshallbe,suchthatthevoltagedropbetweenthesupplyterminaland.fixed current-usingequipmentshallnot exceed4% of thenominalvoltageof thesupplyline,whentheconductorsarecarryingthefull,loadcurrent.4.6 FLEXIBLE CORDS(1) Flexible cordsmaybeusedfor:a) electricalequipmentfor householdor similarusehavinga ratingof 16~OAor lessatvoltagesnotexceeding230.0Vandwhichis intendedto bemovedfromplacet-oplace~.b) electricalequipmentfor industrialusewhichmustbecapableofbeingmovedfromplaceto placefor operation;c) pendants;d) theconnectionof stationaryequipmentto facilitateits fnterchange;e) theconnectionof electricalcomponentsbetweenwhichrelativemotionis necessary;f) theconnectionof appliancessuchasrangesandclothesdryers;g) 'supplyingof currentof portablelampsandotherdevicesor exhibitionpurposes;h) wiring of cranesandhoists.70 EBCS-10 1995 ETHIOPIAN BILDING CODE STANDARDSECTION 4: CONDUCTORS4.8 MAXIMUM PERMISSIBLE TEMPERATURE(1) Colour identificationof conductorsshallbeasspecifiedin Tables4.1anr 4.2 V'EBCS-10 1995 71OF CONDUCTORSOLOETHIOPIAN BUILDING CODE STANDARDb) attemperatureabovethetemperatureratingof thecordor ata temperaturesufficientlylow asto be liableto resultin damageto theinsulationor overallcovering;i) pennanentlysecuredto anystructuralmember;orii) run throughholesin walls,ceilings,or floors;oriii) run throughdoorways,windows,or similaropenings;c) for thesuspensionof anydeviceweighingmorethan2.3kgunlessthecordanddeviceassemblyaremarkedascapableof supportinga weightupto11.Okg.a) asa substitutefor thefixedwiring of structuresandshallnotbe:(1) Any cablemustbecapableof withstandingthemaximumexpectedshort-circuitcurrentinits circuit for the maximumexpecteddisconnectiontime of its protectivedevicewithoutexceedingthemaximumpennissibletemperaturegivenin Table4.3 ,,/(4) Wherea flexiblecord is usedasan extensioncordor to plug intoan applianceor otherdevice,no live partsshallbeexposedwhenoneendis connectedto a sourceof supplyandtheotherendis free.4.7(3) Flexiblecordshallbeprotectedby insulatingbushingor in someotheracceptablemannerwhereit entersor passesthroughtheenclosurewall or thepartitioningof a deviceor entersalampholder.(2) Flexiblecordshallnotbeused:ELECTICAL INSTALLATION OF BUILDINGSTable4.1 Colouridentificationof coresof flexiblecablesandcordsNumberof cores Functionof coreColour(s) of core1PhaseBrownNeutralBlueProtectiveGreen-and-yellow'2PhaseBrownNeutralBlue3PhaseBrownNeutralBlueProtectiveGreen-and-yellow4 or 5PhaseBrownor blackNeutralBlueProtective.Green-and-yellowTable4.2 Colouridentificationof coresof non-flexiblecableandbareconductorsfor fixedwiringFunction I ColouridentificationProtective (includingearthing)conductorPhase of a.c. single - phase circuitNeutral of a.c. single or three-phasecircuitPhase R of 3- phase circuitPhase Y of 3-phase a.c. circuitPhase B of 3-phase a.c. circuitPositive of d.c. 2-wirecircuitNegative of d.c. 2-wirecircuitOuter(positiveor negative)of d.c.2-wirecircuitderivedfrom3-wiresystemPositive of 3-wired.c. circuitMiddle wire of 3-wired.c. circuitNegative of 3-wired.c. circuitGreen and yellowred or yellow or blueblackredyellowblueredblackredredblackblue72 EBCS-1 0 1995 ETHIOPIAN SILOING CODE STANDARDSECTION 4: CONDUCTORSTable4.3 MaximumconductoroperatingtemperatureConduct ConductorUmltlngfinalorInsulationmaterial operatingtemperaturematerialtemperatureCCCopper70C p.v.c (general purpose) 70160/140t60C rubber602008SoC rubber8522090C thermosetting90250Impregnated paper80160CopperMineral- Plastic covered or exposed to70 (sheath)160touch105 (sheath)250- Bare and neither exposed to touchnor in contact withcombustible materials70C p.v.c (general purpose)70160/140tAluminiu85C p.v.c 85160/140tm60C rubber 6020085C rubber8522090C thermosetting90250Impregnated paper80160t above300.6m2ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 73ANNEXPREFACE TO THE TABLES IN ANNEX At ANDANNEX Btt FO,R CABLES AND FLEXIBLE CORDSA.I BASIS OF TABULATED CURRENT-CARRYING CAPACITYThecurrent-carryingcapacitysetoutinAnnexB takesaccountof IEC Publica~ion364-5-523(1983),so far asthe lateris applicable.For typesof cablenottreatedin theIEC publication(e.g.annouredcables),thecurrent-carryingcapacityof Annex B is basedon dataprovidedby ERA TechnologyLtd.ttt, andthe BritishCable Makers' Confederation(see also ERA Report 69-30 'currentRating StandardsforDistributionCables'),The tabulatedcurrent-carrying'capacityrelatesto continuousserviceandis alsoknownasthefull thermalcurrentrating'of thecable,correspondingto theconductoroperatingtemperatureindicatedin theheadingsto thetablesconcerned.It is intendedto providefor asatisfactorylife of conductorandinsulationsubjectto thethermaleffectsof carryingcurrentfor sustainedperiodsin normalservice. A cablemaybe seriouslydamaged,leadingtoearlyfailure,or itsservicelifemaybesignificantlyreduced,if it isoperatedfor anyprolongedperiodata temperaturehigherthanthe indicatedvalue.In addition,thereareotherconsiderationsaffectingthechoiceof thecross-sectionalareaof aconductor,suchas the requirementsfor protectionagainstelectricshock,protectionagainstthermaleffects,overcurrentprotection(seeA.5 below),voltagedrop(seeA.7 below)andthelimitingtemperaturesfor terminalsof equipmentto whichtheconductorsareconnected.t AnnexA: Correctionfactorstt AnnexB: Current-carryingcapacityandvoltagedropttt ERA TechnologiesLtd,CleaveRoad,Leatherhead,SurreyKT227SA74 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 4: CONDUCTORSThetabulatedcurrent-carryingcapacityrelatesto a singlecircuit in the instanationmethodsshownin AnnexA of Section8, in anambientair temperatureof 30C.The currvELECTRICAL INSTALLATION OF BUILDINGSA.2.3 OtherfrequenciesIn extremecases,notablyfor largemulticorecables,thereductionin current-carryingcapacityof cablescarrying,for example,balanced400.0Hza.c. comparedwith the current-carryingcapacityat50.0Hz,maybeasmuchas50%. For smallcablesandflexiblecords,suchasmaybeusedtosupplyindividualtools,thedifferencein the50.0Hzandthe400.0Hzcurrent-carryingcapacitiesmaybenegligible.A.3 EFFECTIVE CURRENT-CARRYING CAPACITYThecurrent-carryingcapacityof acablecorrespondstothemaximumcurrentthatcanbecarriedin specifiedconditionswithouttheconductorsexceediQgthepermissiblelimit of steadystatetemperaturefor thetypeof insulationconcerned.The valuesof tabulatedcurrentrepresenttheeffectivecurrentcarryingcapacityonlywherenocorrectionfactor is applicable;otherwise,the current-carryingcapacitycorrespondsto thetabulatedvaluemultipliedbytheappropriatefactoror factorsfor ambienttemperature,groupingandthermalinsulation,l!S applicable.Irrespectiveof the type of overcurrentprotectivedevice associatedwith the conductorsconcerned,the ambienttemperaturecorrectionfactorsto be usedwhen calculatingcurrent-carryingcapacity(as opposedto thoseusedwhenselectingcablesizes)are thosegiven inTableA.4.A.4 RELATIONSHIP OF CURRENT-CARRYING CAPACITY TSECTION 4: -CONDUCTORSIn the nominalcurrentor currentsettingof the device.protectingthe circuit against /'overcurrent.12 theoperatingcurrent(Le. thefusingcurrentor trippingcurrentfor theconventionaloperatingtime)of thedeviceprotectingthecircuitagainstoverload.G - A correctionfactorto beappliedwheretheinstallationconditionsdiffer fromthoseforwhich valuesof currentcarryingcapacityare tabulatedin Annex B. The variouscorrectionfactorsareidentifiedasfollows:c. for ambienttemperatureCg for groupingCj for thermalinsulationCt for operatingtemperatureof conductor.In all circumstances,Iz mustbenot lessthanIb,andInalsomustbenot lessthanlb.Wherethe overcurrentdeviceis intendedto affordprotectionagainstoverload,12 mustnotexceed1.451.andIn mustnotexceedIz (seeA.5 below).Wherethe overcurrentdeviceis intendedto afford shortcircuit protectiononly, In can begreaterthanIz and12canbegreaterthan1.451z.A.5 OVERLOAD PROTECTIONWhereoverloadprotectionis required,the type of protectionprovideddoesn9t affect thecurrent-carryingcapacityof a cablefor continuousservice(lz), but it mayaffectthechoiceofconductorsize. The operatingconditiQnsof a cableare influencednot only by the limitingconductortemperatureforcontinuousservice,butalsobytheconductortemperaturewhichmightbeattainedduringtheconventionaloperatingtimeof theoverloadprotectiondevice,in theeventof anoverload.Thismeansthattheoperatingcurrentof theprotectivedevicemustnotexceed1.45Iz.Wheretheprotectivedeviceis afuseor aminiaturecircuit-breaker,thisrequirementissatisfiedby selectingavalueof Iz not lessthanInIn practice,becauseof thestandardstepsin nominalratingof fusesandcircuit-breakers,it isoftennecessaryto selectavalueof Inexceedinglb' In thatcase,becauseit is alsonecessaryforETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 77ELECTRICAL INSTALLATION OF BUILDINGSIz in turnto benot lessthantheselectedvalueof Iu, thechoiceof conductorcross-sectionalareamay be dictatedby the overloadconditionsand the current-carryingcapacity(IJ of theconductorswill not alwaysbefully used.The size neededfor a conductorprotectedagainstoverloadby a semi-enclosedfusecan beobtainedby theuseof a correctionfactor,1.45/2=0.725,whichresultsin thesamedegreeofprotectionasthataffordedby otheroverloadprotectivedevices.This factoris to beappliedtothenominalratingof thefuseasa divisor,thusindicatingtheminimumvalueof -4 requiredoftheconductorto beprotected.In thiscasealso,thechoiceof conductorsizeis dictatedby theoverloadconditionsandthecurrent-carryingcapacity(IJ of theconductorscannotbefully used.A.6 DETERMINATION OF THE SIZE OF CABLE TO BE USEDHaving establishedthe designcurrent(Ib) of thecircuit underconsideration,the appropriateproceduredescribedin A-6.1 to A-6.4 belowwill enablethedesignerto determinethesizeofthecablethatwill benecessaryto use.As a preliminarystep,it is usefulto identifythe lengthof thecablerun andthepermissiblevoltagedropfor theequipmentbeingsupplied,asthismaybeanover-ridingconsideration(seeA.7 below).The permissiblevoltagedropin mV,dividedby Ib andby the lengthof run, willgivethevalueof voltagedropin mv/Almwhichcanbetolerated.A voltagedropnotexceedingthatvalue is identifiedin theappropriatetableandthecorrespondingcross-sectionalareaofconductorneededonthisaccountcanberead-offdirectlybeforeanyothercalculationsaremade.The conductorsizenecessaryfromconsiderationof theconditionsof normalloadandoverloadis then detennined. All correctionfactorsaffectingIz (that is, the factorsfor ambienttemperature,groupingandthermalinsulation)can,if desired,beappliedto thevaluesof -4 asmultipliers. This involvesa processof trial anderroruntil a cross-sectionalareais reachedwhich ensuresthat Iz is not lessthanIbandnot lessthanIu of any protectivedevicethat isintendedto select. In anyevent,if a correctionfactotfor protectionby a semi-enclosedfuseisnecessary,thishastobeappliedto Iu asadivisor. It is, therefore,moreconvenientto applyallthecorrectionfactorsto Inasdivisors.This methojlis u'sedin A.6.1 throughA.6.3 andproducesavalueof currentandthatvalue(orthenextlargervalue)canreadilybelocatedin theappropriatetableof current-carryingcapacityandthecorrespondingcross-sectionalareaof conductorcanbeidentifieddirectly. It shouldbenotedthatthevalueof -4 appearingagainstthechosencross-sectionalareais not Iz. It is not78 ~EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD,(AI)SECTION 4: CONDUCTORSnecessaryto knowIz wherethesizeof conductoris chosenby thismethod;but if it is desiredto identifyIz thevalueis determinedby themethodindicatedin A.3 above.However,this methodcannotbe used.for cablesinstalledin enclosedtrenches(InstallationMethods18,19and20of AnnexA, Section8)becausethecorrectionfactorsgivenin TableA3arerelatedto conductorcross-sectionalareas.For suchcables,it is, therefore,necessaryto usetheprocessof trial anderrordescribedabove,selectingona trialbasisa particularsizeof cablefrom, for instance,voltagedropconsiderations.A.6.1' Overloadprotectionaffordedby a fuseor a miniaturecircuitsbreaker(1) For singlecircuits- dividenominalcurrentof theprotectivedevice(In)by anyapplicablecorrectionfactorfor ambienttemperature(CJ givenin TableAA.- thenfurtherdivideby anyapplicationfor thermalinsulation(CJ(2) The sizeof cableto be usedshallbe suchthatits tabulatedcurrent-carryingcapacity(~)give in Equation(AI) below is not lessthanthevalueof nominalcurrentof theprotectivedeviceadjustedasabove:~~J! -I) (Ampere)Ca~:(3) For groups- divide the nominalcurrentof the protectivedevice(In) by the correctionfactor forgrouping(Cg) givenin Table::.A.l, A.2' or A.3:(A2)Alternatively,it maybeselectedin accordancewith thefollowing formulae,providedthatthecircuitsof thegrouparenot liableto simultaneousoverload:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 79------~--~----~---~--~~---~--~---~----~--~---~ELECTRICAL INSTALLATION OF BUILDINGS(A.3)and(AA)(Ampere).[1 e2lI:+0.48/; ~/t'c;; Ct.'The size of cableto be usedshall be suchthat its tabulatedsingle-circuitcurrent-ca.rrYingcapacity(It) is not lessthanthevalueof It calculatedin accordancewith Equation(A.2) ab~veor,whereEquations.(A.3)and(A.4) areused,notlessthanthelargerof theresultingtwovaluesof~.WherecorrectionfactorsC. and/orCj areapplicable,theyareto beappliedas divisorsto thevalueof It determinedby theaboveformulae.A.6.2 Protectiondevicea semi-enclosedfuse(1) For singlecircuits- dividedthe nominalcurrentof the fuse(In) by any applicablecorrection.factorforambienttemperature(CJ givenin TableA.Sj- thenfurtherdivideby anyapplicablecorrectionfactorfor thermalinsulation,(Cj);J ~thenfurtherdivideby 0.725.The sizeof cableto beusedshallbesuchthatitstabulatedcurrent-carryingcapacity(~)is notlessthanthevalueof nominalcurrentof thefuseadjustedasabove:(A. 5)80 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD/'SECTION 4: CONDUCTORS(2) For groups- dividedthenominalcurrentof thefuseIn by 0.725andby the applicaolecorrectionfactorfor grouping(Cg) givenin TablesAI, A2 ,or AJ(A6)Alternatively,it maybe selectedby thefollowing formulae,providedthatthecircuitsof thegrouparenot liableto simultaneousoverload.(A7)and(AS)(Ampere)The size of cableto be usedshall be suchthat its tabulatedsingle-circuitcurrent-carryingcapacity(It) is not lessthanthevalueof It calculatedin accordanc;with Equation(A6) aboveor,whereEquation(A7) and(AS) areused,not lessthanthelargerof theresultingtwovaluesof It.(J) WherecorrectionfactorsC. and/orCj areapplicable,theyareto be appliedasdivisorsto-thevalueof It determinedby theaboveEquation.A.6.3 OverloadprotectionnotrequiredWherethecableunderconsiderationis notrequiredtobeprotectedagainstoverload,thedesigncurrentof thecircuit (Ib) is to bedividedby anyapplicablecorrectionfactors,andthesizeofthe cableto be usedshall be suchthat its tabulatedcurrent-carryingcapacity(It)givenbyETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 81ELECTRICAL INSTALLATION OF BUILDINGSEquation(A.9) below for the installationmethodconcernedis not lessthanthe valueof Ibadjustedasabove:(A.9)(Ainpere)A.6.4 Variationof installationconditionsalonga cablerouteTheproceduresin A.6.1 throughA.6.3abovearebasedontheassumptionthatall theconditionsnecessitatingtheuseof correctionfactorsapply,tothesamepartof therouteof theconductorsof the circuit. Wherevariousfactorsapplyto differentpartsof theroute,eachpartmaybetreatedseparatelyor, alternatively,only thefactoror combinationof factorsappropriateto theroostonerousconditionsencounteredalongtheroutemaybeappliedto thewholeof theroute.It is permissibleto obtain more precisefactorsby calculationof the various conductortemperaturerisesthatwill occur alongsucha route,providedthatthe appropriatelimitingtemperatureof theconductoris nowhereexceeded.A.7 TABLES OF VOLTAGE DROPIn thetables,valuesof voltagedroparegivenfor a currentof oneamperefor a metrerun, i.e,for adistanceof 1.Omalongtheroutetakenbythecables,andrepresenttheresultof thevoltagedropsin all thecircuitconductors.The valuesof voltagedropassumethattheconductorsareat theirmaximumpermittednolffialoperatingtemperatures.The valuesin thetables,for a.c.operation,applyonly to frequenciesin therange49.0Hzto61.0Hz;and for single-corearmouredcables,thetabulatedvaluesapplywherethe armourisbondedto earthat both ends.- The valuesof voltagedrop for cablesoperatingat higherfrequenciesmaybe substantiallygre&ter.For a given run, to calculatethe voltagedrop (in mY) the tabulatedvalue for the cableconcernedhasto bemultipliedby thelengthof therun in metresandby thecurrentthecableis intendedto carry;namely,thedesigncurrentof thecircuit(Ib) in amperes.For three-phasecircuits,thetabulatedmV/AIm valuesrelateto the line voltageandbalancedconditionshavebeenassumed.82_'EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 4: CONDUCTORSForcableshavingconductorsof 16.0mm2or lesscross-sectionalarea,theirinductancescanbeignoredand(mV/Alm)rvaluesonly aretabulated.For cableshavingconductorsgreaterthan16.0mm2cross-sectionalarea,theimpedancevaluesaregivenas(mV/Alm)z,togetherwith theresistivecomponent(mV/Alm)randthereactivecomponent(mV/Alm)xThedirectuseof thetabulated(mV/Alm)ror (mV/Alm)zvalues,as appropriate,may leadtopessimisticallyhighcalculatedvaluesof voltagedropor, in otherwords,to unnecessarilylowvaluesof permittedcircuit lengths. For example,wherethe designcurrentof a circuit issignificantlylessthanthe effectivecurrent-carryingcapacityof the cablechosen,the actualvoltagedropwould be lessthanthecalculatedvaluebecausetheconductortemperature(and,hence,its resistance)will be lessthanthatonwhichthetabulatedmV/Aim hadbeenbased.Asregardspowerfactorin a.c.circuits,theuseof thetabulatedmV/Aim values,(for thelargercablesizes,thetabulated(mV/Alm)zvalues)to calculatethevoltagedropis strictlycorrectonlywhenthephaseangleof thecableequalsthatof theload. Whenthephaseangleof thecabledoesnotequalthatof the load,thedirectuseof thetabulatedmV/Aim or (mV/Alm)zvaluesleadsto a calculatedvalueof voltagedrophigherthantheactualyalue.In somecases,it maybeadvantageousto takeaccountof theloadpowerfactorwher calculatingvoltagedrop.Wherea moreaccurateassessmentof voltagedropis desirablethefollowing methodsmaybeused.(a) Correctionfor operatingtemperatureshallbecarriedasfollows:For cableshavingconductorsof cross-sectionalarea16.0mm2or less,the designvalueofmV/Aim is obtainedby multiplyingthetabulatedvalueby a factorCt, givenbyc=t230 +12t - (CC - ~)(t - 30)p a g i pt230 + tp(A. 10)where~ is themaximumpermittednormaloperatingtemperature,DC.Equation(A.10) appliesonly wheretheovercurrentprotectivedeviceis otherthana fuseandwheretheactualambienttemperatureis equalto or greaterthan30C.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 83ELECTRICAL INSTALLATION OF BUILDINGSNote: For convenience,theabovefonnula is basedontheresistance-temperaturecoefficientof 0.004perC at20C for both copperandaluminiumconductors.For cableshavingconductorsof cross-sectionalareagreaterthan 16.0mm2,only theresistivecomponentof the voltagedrop is affectedby thetemperatureandthe factorCt, is thereforeappliedonly to thetabulatedvalueof (mV/Alm),andthedesignvalueof (mV/Alm)z is givenby thevectorsumof Ct (mV/Alm),and(mV/Alm)x'For very largeconductorsIzeswheretheresistivecomponentof voltagedropis muchlessthanthecorrespondingreactivepart(i.e whenx/r~3)thiscorrectionfactorneednotbeconsidered.(b) Correctionfor loadpowerfactorFor cableshavingconductorsof cross-sectionalareaof 16.0mm2or less,thedesignvalueofmV/Aim is obtainedapproximatelyby multiplyingthetabulatedvalueby thepowerfactorofthe load,CDS ~.For cableshavingconductorsof cross-sectionalareagreaterthan16.0mm2thedesignvalueofmV/Aim isgivenapproximatelyby:CDS ~ [tabulated(mV/Aim),]+sin~ [(tabulated(mV/Alm)xlFor single-corecablesin flat formation,thetabulatedvaluesapplyto outercablesandmayunderestimatefor the voltagedrop betweenan outercableand the centrecable for cross-sectionalareasabove240.0mm2andpowerfactorsgreaterthan0.8.(c) Combinedcorrectionfor bothoperatingtemperatureandloadpowerfactorFrom (a) and(b) above,whereit is consideredappropriateto correctthetabulatedmV/Aimvaluesfor bothoperatingtemperatureandloadpowerfactor,thedesignvaluesof mV/Aim aregivenasfollows:i) For cableshavingconductorsof 16.0mm2or lesscross-sectionalarea:Ct CDS ~ (tabulatedmV/Alm)ii)For cableshavingconductorsof cross-sectionalareagreaterthan16.0mm2:CtCDS ~ (tabulatedmV/Alm),)+sin ~ (tabulatedmV/Alm)x)'84 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDANNEX A (NORMATIVE)CORRECTION FACTORSTableA.I: Correctionfactorsforgroupsof morethanonecircuitofsingle-corecables,or morethanonemulti~orecable([0beappliedtothecorrespondingcurrent-carryingcapacityfor a singlecircuitin TablesB.I throughB.8,B.9throughB.16,B.l7 throughB.l9,B.20,B.2?,B.28,B.31throughB.38,B.39throughB.46t)-7~.,Reference method of installation(see Annex 8-A of Section 6) ./ Correction factor (C~Number of circuits or multicorecables ../'23456769101214161620Enclosed(Method3 or4) orbunchedandclippeddirecttoa non-metallicsurface(method1) 'V0.600.700.650.600.570.540.520.500.460.450.430.410.390.38Touching0.650.790.750.730.720.720.710.70------Single layerclipped to non-metallicsurface (Method 1) Spacedtt0.940.900.900.900.900.900.900.900.900.900.900.900.900.90! Touching0.660.81I 0.770.70,740.730.730.720.710.70----Singlelayermulticoreon a perforatedmetalcabletray,verticalorhorizontal(method11)Spacedtt#0.910.690.660.60.67---------Horizontal0.900.65------,,--- ,Single layersingle core on a perforatedmetalcable tray,touching (Method 11)Vertical0.65,--,-------,-Single layer multicoretouching on ladder supports (Method 13)0.660.620.600.790.760.760.760.77--- ---;/.1Il.-l;',J.-'tJ.:rJ,b'c9-/ELECTRICAL INSTALLATION OF BUILDINGSU'f~(~~!StTable A.2 Correction factorsfor mineral insulatedcablesinstalledonperforatedtray(To beAppliedtotheCorrespondingCurrent-CarryingCapacityfor SingleCircuitsforReferenceMethod11~TableB.27)Notesto TablesA.I andA.2(i) Thefactorsin theTablesareapplicabletogroupsof cablesallof onesize.Thevalueof currentderivedfromapplicationof theappropriatefactorsis themaximumcurrentto becarriedbyany{)fthecablesin thegroup.(ii) If, duetoknownoperatingconditions,acableisexpectedtocarrynotmorethan30%of itsgroupedrating,itmaybeignoredforthepurposeofobtainingtheratingfactorof itsgroupedrating,itmaybeignoredforthepurposeofobtainingtheratingfactorfortherestofthegroup.Forexample,agroupofN loadedcableswouldnormallyrequireagroupreductionfactorofCgappliedtothetabulated~.H,owever,if M cablesinthegroupcarryloadswhicharenotgreaterthanO.3CgLtamperestheothercablescanbesizedbyusingthegroupratingfactorcorrespondingto(N-M) cables.l~lI~lcII~'Cc,(CIc.!'C~C~I.!Ic1~Ic1I(I;,Tray NumbNumber of multicore cables or circuitsOrientationArrangement of cables er ofTrays123. 469HorizontalMulticonductor cables touching11.00.900.800.800.750.75HorizontalMulticonductor cables spacedt11.01.01.00.950.90-VerticalMulticonductor cables touching11.00.900.800.750.750.70VerticalMulticonductor cables spaced t11.00.900.900.900.85.HorizontalSingle conductor cables trefoil11.01.00.95separatedtt VerticalSingle conductor cables trefoil11;00.900.90separatedttSpacedby a clearancebybetweenadjacentsurfacesof atleastonecablediameter(Dc)Spacedby a clearancebetweenadjacentsurfacesof atleastonecablediameter( 2De).ttt(iii) Whencableshavingdifferingconductoroperatihrgtemperaturesaregroupedtogether,thecurrentratingshallbebasedonthelowestoperatingtemperatureof anycablein thegroup.(iv) Wherethehorizontalclearancesbetweenadjacentcablesexceeds2Dc,nocorrectionfactorneedbeapplied.86 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD ~~0){~~'0o~JTableA.3 - CorrectionfactorsCorcablesinstalledin enclosed1:renches~taIlation Methods18, 19and20of AnnexA, Section8yt j' l' e-vCf ~[qq7 .Thecorrectionfactmstabu1atedbelowrelatetothedi'l'ition of cableillustratedm lremNo. 18to lremNo.20of AnnexA, Soroon8,andare'1'Plicabletothecurren~~.capacitiesfor ReferenceMethods 12or 13of Annex A, Section8, asgivenin therelevanttablesof this Annex.Installation Method 18Installation Method 19Installatior:lMethod 20conductor cross-6 single- core6 single- core' 12 single-core12 single-18 single-core24 single-sectional area2 single-core3 single-core4 single-corecables, 4 two-cables, 4 two-8 single-corecables, 8 two-core cables,cables, 12core cables,[mm~cables, or 1cables, or 2cables, or 2core cables,core cables,cables, or 4core cables,8 two-coretwo-core16 two-corethree- or four-two-corethree- or four-or 3 three- oror3 three- orthree- or four-or 6 three- orcables, or 6cables, or 9cables, or 12core cablecablescore cablesfour-corefour- corecore cablesfour-corethree- or four-three- or four-three- or four-cablescables cablescore cablescore cablescore cablesr1 23456789101140.930.900.870.820.860.830.760.810.740.6960.920.899.860.810.860.820.750.800.730.68100.910.880.850.800.850.800.740.780.720.66160.910.870.840.780.830.780.710.760.700.64250.900.860.820.760.810.760.690.740.670.62350.890.650.810.750.800.740.680.720.660.60500.880.840.790.740.780.730.660.710.640.59700.870.820.780.720.770.720.640.700.620.57950.860.810.760.700.750.700.630.680.600.551200.850.800.750.690.730.660.610.660.580.531500.840.780.740.670.720.670.590.640.570.511850.830.770.730.650.700.650.580.630.550.492400.820.760.710.630.690.630.560.610.530.483000.810.740.690.620.680.620.540.590.520.464000.800.730.670.590.660.600.520.570.500.445000.780.720.660.580.640.580.510.560.480.436300.770.71~0.650.560.630.570.490.540.470.41(Y:)-Jt whencableshavingdifferentconductoroperatingtemperaturesaregroupedtogether,thecurrentratingshallbebasedonthelowestoperatingtemperatureof anycablein thegroup.0000TableA.4 Correctionfactorsfor ambienttemperaturewhereprotectionis againstshort-circuit. Note Thistableapplieswheretheassociatedovercurrentprotectivedeviceisintendedtoprovideshort-circuitprotectiononly.Exceptwherethedeviceisasemi-enclosedfuse,thetablealsoapplieswherethedeviceis intendedto provideoverloadprotection.Typeof insulation Operating Ambienttemperaturectemperature253035404550556065707580859095Rubber (flexible cables only)sooe1.041.00.910.820.710.580.41--------General purpose p.V.c.700e1.031.00.940.870.790.710.610.500.35------.Paper800e1.021.00.950.890.840.770.710.630.550.450.32----Rubber8Soe1.021.00.950.900.850.800.740.670.600.520.430.30---Heat resisting p.v.c.t8Soe1.031.00.970.940.910.870.840.790.710.61'0.500.35---ThermosettinggOOe1.021.00.960.910.870.820.760.710.650.580.500.410.29--Mineral'700e sheath1.031.00.930.850.770.670.570.450.31------10Soe 1.021.00.960.920.880.840.800.750.700.650.600.540.470.400.3NOTE: (i) Correctionfactorsfor flexiblecordsandfor 85Cor 150Crubberinsulatedflexiblecablesaregivein therelevanttableof current-carryingcapacity.(ii) Thistablealsoapplieswhepdeterminingthecurrent-carryingcapacityof a cable.(t) Thesefactorsareapplicable~~lyto ratingin Columns2 through5 of TablesB.l andB.2.TableA.5 Correctionfactorsfor ambienttemperaturewheretheoverloadprotectivedeviceis a semi-enclosedfuseAmbient temperature FC]OperatingType of insulationtemperature253035404550556065707580859095FC]Rubber (flexiblecables only)601.041.00.960.910.870.790.56-- ------General purpose p.v.c.701.031.00.970.940.910.870.840.690.48------Paper801.021.00.970.950.920.900.870.840.760.620.43----Rubber851.021.00.970.950.930.910.880.860.830.710.580.41---Heat resisting p.v.c..851.031.00.970.940.910.870.840.800.760.720.680.49Thermosetting0.901.021.00.980.950.930.910.890.870.850.790.690.560.39--Mineral: Bare and exposed to70, sheath1.031.00.960.930.890.860.790.620.42 -touch p.v.c. covered-----Bare and not exposed to105, sheath1.021.00.980.960.930.910.890.860.840.820.790.770.640.550.43touch Thesefactorsareapplicableonlyto ratingsin columns2 to 5 of TablesB.I ~d B.2.Note: Correctionfactorsforflexiblecordsandfor 85Cor 150Crubber-insulatedflexiblecablesaregivenin therelevanttableof current-carryingcapacity../Current-carryingcapacity(Amperes)ANNEX B (NORMATIVE)TYPE OF CABLE AND AMP ACITYTable B.1 Single-coreP.V.C. insulatedcables,non-armoured,with or without sheath(copperconductor)Ambienttemperature : 30CConductoroperatingtemperature:70CReference Method 4 (endosed inReference ~ethod 3 (endosed in IReference Method 11 (on aReference Method 12 (free air)conduit in thermally insulatingconduit on a wall or in trunkingReference Method 1 (dippedperforaled cable tray horizontal Ofdirect)HOfizontaJ flalVertical flalwall etc.)etc.) vertical)spacedspacedTrefoilConductOf cross-3 Of 4 cables3 Of 4 cables2 cables2 cables,sectional area2 cables,3 Of 4 cables2 cables,3 Of 4 cables2 cables,ttYee-phase2 cables,three phasesingle-phasesingle-phase3 cabIes trefoilsingle-phasethree-phasesingle-phasethree-phasesingle-phaseac. flal andsing!e-phaseac. flal andac. Of d.c. Ofac. Of d.c. OfttYee phaseac. Of d.c. flalac. Of d.c. flal3 cables3 cablesac. Of d.c.ac.ac. Of d.c.ac.and touchingtouching Ofand touchingtouching Ofthree-phasettYee-phaseac.trefoiltrefoilac.ac.12345II7a9101112r,II~iti{n;.~~V.~.mm2 mV.mVmV'mV-mV--mY-mY -..mVmV11110.513.51215.514-----1.514.513.517.515.52016-----,2.5 19.51624212725-----4262432263733----6343141364743----10464257506559-----16615676666779-----25607310169114104126112146130110359969125110141129156141161162137501191061511341621671911722191971677015113619217123421424622326125421695162164232207264261300273341311264120210166269239330303349316396362306150240216300262361349404369456419356165273245341296436400463424521460409240320266400346515472549504615569465300367326456394594545635564709659561400- 546467694634732679652795656500- 626533792723635776982920749630- 72061190482695369211381070655800- --103094310861020126511669711000- --1154105812161149142013371079'l',V-{I,p...O.eoc.by - ooen'Ii-enclo~ E'.se. see A.6.2 o the preCace 'to this Ar1nex.TableB.2 Voltagedrop(per ampereper meter)Conductoroperatingtemperature: 70C2 cables - single-phase ac. 3 or 4 cables - thr~phase ac.Conduct 2or cross- cablesReference Methods 3Reference Methods 1 Reference Methods 3sectionalReference Methods 1d.c.and 4 (Enclosed inand 11(clipped orReference Method 12and 4 (Encl~ inReference Methods 1, Reference Method 12areaconduit etc. in or on adirect on trays,(spacedt)conduit etc. in or on a11and 12(in trefoiQand 11(Flatand(flatspaced t)wall)touching) wall ')touching)12 ~ 458789mm2mV mV mVmVmVmVmVmV144 44 4444383838381.529 29 2929252525252.518 18 181815151515411 11 11119.59.59.59.567.3 7.3 7.37.36.46.46.46.4~10 4.4 4.4 4.44.43.83.83.83.8( , -Current-carryingcapacity(Amperes):Table B.3 MulticoreP.V.C.insulatedcables,non-armoured(copperconductors)Ambienttemperature: 30'CConductoroperatingtemperature:70'CReferenceMethod4 (enclosedinanReferenceMethod3 (enclosedinReferenceMethod11 (on a perforatedinsulatedwall,etc.)conduiton a wallor ceiling,or inReferenceMethod1 (clippeddirect)cabletray),or ReferenceMethod13Conductortrunking) (freeair)cross- 1 two-corecablet,sectional 1 two-corecablet1 threecore1 two-corecablet.1 three-core1 two-corecablet1 three-core 1 three-coreareasingle-phasea.c.cablet or I four-single-phasea.c.cablet or I four-single-phasea.c.cabletor 1 four-single-phasecabletor 1 four-corecable,threecorecable,three-corecable,three-a.c. or d.c.core cable,three-or d.c. phasea.c..or d.c.phasea.c.or d.c.phasea.c.phasea.c.12 345G789mm2AAAAAAAA111101311.51513.51714.51.5141316.51519.517.52216.52.516.517.5232027243025425 23302736324034632 293634464151431043395246635770601657526962657694602575669060112961191013592631119913611914612.650110991331161661441601537013912516614921316423219695167150201179256223262236120192172232206299259326276150219196256225344299379319165246223294255392341434364240291261344297461403514430300334296394339530464593497400--470402634557715597t Withor withoutprotectiveconductor.Circularconductorsareassumedforsizesupto and including16.0mm2Valuesfor largersizesrelatetoshapedconductorsandmaysafelybeappliedto circularconductors.Note:Wheretheconductoris to be protectedby a semi-enclosedfuse,see A.6.2of thePrefaceto thisAnnex.~---------------------SECTION 4: CONDUCTORS.TableB.4 Voltagedrop(peramperepermeter)Conductoroperatingtemperature: 70CConductorTwo-coreTwo-core cable single-Three-or four-core cableCross-sectional cable d.c.phase a.c.three-phase a.c.areamm2mVmV mV144 44 381.52929 252.51818 15411 11 9.567.3 7.3 6.4104.44.4 3.8162.82.8 2.4r .x z.J... -~z-- 25 1.751.750.1701.751.500.1451.50351.251.250.1651.251.100.1451.10500.93,0.930.1650.940.800.1400.81700.630.630.1600.650.550.1400.57950.460.470.1550.500.41Q.1350.431200.360.380.1550.410.330.1350.351500.290.300.1550.340.260.1300.291850.230.250.1500.290.210.1300.252400.1800.1900.1500.240.1650.1300.213000.1450.1550.1450.210.1350.1300.185400'0.1050.1150.1450.1850.1000.1250.160ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 930~ ,Current-Carrying Catpacity (Amperes):TableB.S Single-corearmouredP.V.C.insulatedcables,non-magneticarmour(copperconductors)Conductor operating temperature: 700cReference Method 1Reference Method 11 on a Reference Method 12 (free air)(clipped direct)perforated cable tray2 cables single-phase a.c.2 cables d.c.3 or 4 cables, three-phase a.c.Conductorcross-2 cables,3 or 42 cables,3 or 4sectionalsingle-phasecables,shingle-cablesHorizontalVertical flatHorizontalVertical,HorizontalVertical flat3 cablesareaa.c. or d.c.three-phasephase a.c.three~phaseflat anda.c. flat andflat anda.c. andflat spacedspacedspacedspacedflat spacedspacedtrefoiltouchingtouchingtouchingtouching123456789101112-mm2AAAAAAAAAAA5019317920518922921722921623021218170245225259238287272294279286,263231952962693132853493323573403383132801203423093603274013834153963853573241854473994694225114895485254904564252405254655504925935686486225665285013005945156245476686407487196165785674006875757236187377078858516746326575007636228056738fO77710359977216767316308436698917288938561218117477172380980091971097677794390514411390824772088610009757371041808100896716851627872816945Note: Wheretheconductoris to be protectedby a semi-enclosedfuse,seeA.6.2of thePrefaceto thisAnnex.TableB.6 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:70C0VI2 cables - single-phase a.c.3 or 4 cables - three-phac;ea.c.Conductor cross-2 cables d.c.Reference Methods 1,Reference Methods 1sectional areaReference Methods 1Reference Method Reference Method 12'.and 11 (Touching)12 (spacedt)11 and 12 (in trefoiland 11 (Flat and(Flat spacedt)touching)touching)1234 5e7mm2mVmVmVmVmVmVrxzrxz rxz rxz rxz500.930.930.220.950.920.300.970.800.1900.820.790.260.84 0.790.340.86700.630.640.210.680.660.290.720.560.1800.580.570.250.62 0.590.320.68950.460.480.200.520.510.280.580.420.1750.450.440.250.50 0.470.310.571200.360.390.1950.430.420..280.500.330.1700.370.360.240.43 0.400.300.501500.290.310.1900.370.340.270.440.270.1650.320.300.240.38 0.340.300.451850.230.260.1900.320.290.270.390.220.1600.270.250.230.34 0.290.290.412400.1800.200.1800.270.230.260.350.175 0.1600.230.200.230.30 0.240.280.373000.1450.1600.1800.240.190 0.260.320.140 0.1550.210.165 0.220.280.200.280.344000.1050.1400.1750.220.180 0.240.300.120 0.1300.1950.160 0.210.0260.210.250.325000.0860.1200.1700.210.165 0.230.290.105 0.1450.1800.145 0.200.250.190 0.240.306300.0680.1050.165 0.1950.150 0.220.270.091 0.1450.1700.135 0.1950.230.175 0.220.288000.0530.0950.160 0.1850.145 0.210.250.082 0.1400.1600.125 0.1800.220.170 0.195 0.2610000.0420.0910.155 0.1800.140 0.1900.240.079 0.1350.1550.125 0.1650.210.165 0.170 0.24t, Spacingslargerthanthosespecifiedin Method12(seeAnnexA. Section8)will resultin largervoltagedrop.ELECTRICAL INSTALLATION OF BUILDINGSTableB.7 MulticorearmouredP.V.C.immlatedcables(copperconductor)Current-carryingcapacity(Amperes):Ambienttemperature:30CConductoroperatingtemperature:700CConductor Reference Method 1Reference Method 11 (on across-sectional(Clipped direct)perforated horizontal or vertical cableareatray), or Reference Method 13 (freeair)1 two-core cable,1 three or four1 two-core cable,1 three or fourSingle-phase a.c. core cable,single-phasecore cable,or d.c. three-phase a.c.a.c. or d.c.three-phase a.c.12345mm2AAAA1.5211822192.528253126438334135649425345'106758726216897797,832511810212811035145125157135501751511901637022219224120795269231291251120310267336290150356306386332185405348439378240476409516445300547469592510400621540683590Note:Wheretheconductoris tobeprotectedbya semi-enclosedfuse,seeA. 6.2of thePrefaceto thisAnnex.96 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 4: CONDUCTORSTableB.8 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:70CConductorTwo-core cableTwo-core cable single-three or four-core cable,cross- d.c.phase a.c. three-phase a.c.sectional area12 3 4mm2mV mV mV1.529 29 252.518 18 15411 11 9.567.3 7.3 6.4104.4 4.4 3.8162.8 2.8 2.4rxzr x z251.751.750.1701.751.500.1451.50351.251.250.1651.251.100.1451.10500.930.930.1650.940.800.1400.81700.630.630.1600.650.550.1400.57950.460.470.1550.500.410.1350.431200.360.380.1550.410.330.1350.351500.290.300.1550.340.26Q.1300.291850.230.250.1500.290.210.1300.252400.1800.1900.1500.240.1650.1300.213000.1450.1550.1450.210.1350.1300.1854000.1050.1150.145 0.1850.1000.1250.160ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 97000 Table B.9 Single-core cables having thermosetting insulation, non-armoured, with or without sheath(copper conductors)Current carryingcapacity(Amperes): Ambient temp~rature:30CConductor operatingtemperature:90CReference Method 4 (enclosedReference Method 3 (enclosed Reference Method 11 (on aReference Method 12 (fee air)Conduct in conduit in thermallyin conduit on a wall or in ... Reference Method 1 (clippedperforated cable tray horizontalor Insulating wall etc.)trunking etc.)direct)or verticalHorizontal flatVertical flatcross- spaced,spacedTrefoilsectiona I area3 or 4 cables3 or 42 cables,2 cables,2 cables2 cables2 cables3 or 4 cables2 cables3 or 4 cablessingle-phasethree-phasesingle-phase. cables three-single phasesingle-phase3 cables,single phasethree- phasesingle phasethree- phaseac. or d.c. flatac. flat andac. or d.c. flatphase ac. flatac. or d.c. orac. or d.c. ortrefoil three-ac. or d.c.ac.a.c. or d.c.ac.and touchingtrunking orand touchingand touching3 cables3 cablesphase ac.trefoilor trefoilthree-phasethree-phase12 3456789101112114 1317151917.5-----1.5181722192523-----2.5242330263431-----433 3040354641-----643 3951455954-----10585371638174-----1676 70958510999-----251009112611114313015814018316313835124111156138176161195176226203171501491351891682282092932152742462097018917024021429326830827935131827095228205290259355326375341426389330120263235336299413379436398495453385150300270375328476436505461570524445185341306426370545500579530651600511240400358500.rt33644590686630769711606300459410573493743681794730886824701400--6835848687939158491065994820500- -783666990904104497312281150936630- -9007641130103311911115142313381069800,- ---12881179135812751581148512141000----14431323152014361n516711349Note: Wheretheconductoris to'beprotectedby a semi-enclosedfuse,seeA.6.2of thePrefaceto thisAnnex.The current-carryingcapacityinColumm2to5 arealsoapplicableto flexiblecableswherethecablesareusedin fixedinstallations.For cablein rigidp.v.c.conduit,thevaluesstated~~>~':..~e.::...~}..~?.?_~!_~~:.~~~~::,~:';.:.~~~reaconductoroperatesatatemperatureexceeding7cPC.it shallbeascertainedthattheequipmentconnectedtotheconductorissuitableTableB.10 Voltagedrop(peramperepermeter)Conductor operatingtemperature:90C2 cables,single-phasea.c. 3 or 4 cables-three-phase.a.c.ConductoReferenceReferenceMethodReference2Methods3 and1 and 11 (ClippedReferenceMethodMethods3 and4ReferenceReferenceReferencer cross Cable4(Enclosedin (EnclosedinMethods1, 11,Methods1 and 11Methods12 (Flatsectional s d.c.conduitetc. inordirector on trays,12 (Spacedt )conduitetc. inorand 12 (In trefoil)(Flattouching)spacedt)area on a wall)touching)on a wall)12 3 456789mm2mVmV mVmVmVmVmVmV146 46 4646404040401.531 31 3131272727272.519 19 191916161616412 12 12121010101067.9 7.9 7.97.96.86.86.86.8104.7 4.7 4.74.74.04.04.04.0162.9 2.9 2.92.92.52.52.52.5rxzr xzr xzr xzr xzr xzr xz251.851.850.311.901.85 0.1901.851.850.281.851.600/2.71.651.600.1651.601.600.190 1.601.600.271.65351.351.350.291.351.35 0.1801.351.350.271.351.150.25 1.151.150.1551.151.150.180 1.151.150.261.20500.991.000.291.050.99 0.1801.000.990.271.000.870.25 0.900.860.1550.870.860.180 0.870.860.260.89700.680.700.280.750.68 0.1750.710.680.260.730.600.24 0.650.590.1500.610.590.175 0.620.590.250.65950.490.510.270.580.49 0.1700.520.490.260.560.440.23 0.500.430.1450.450.430.170 0.460.430.250.491200.390.410.260.480.39 0.1650.430.390.250.470.350.23 0.420.340.1400.370.340.165 0.380.340.240.421500.320.330.260.430.32 0.1650.360.320.250.410.290.23 0.370.280.1400.310.280.165 0.320.280.240.371850.250.270.260.370.26 0.1650.300.250.250.360.230.23 0.320.220.1400.260.220.165 0.280.220.240.332400.1900.210.260.330.20 0.1600.250.1950.250.310.185 0.22 0.290.170 0.140 0.220.170 0.165 0.240.1700.240.293000.1550.175 0.250.310.10 0.1600.220.1550.250.290.150 0.22 0.270.140 0.1400.1950.135 0.160 0.210.1350.240.274000.1200.140 0.250.290.1300.1550.200.1~50.240.270.125 0.22 0.250.110 0.1350.1750.110 0.1600.1950.1100.240.265000.0930.120 0.250.280.1050.155 0.1850.0980.240.260.100 0.22 0.240.090 0.1350.1600.088 0.1600.1800.0850.24 0.256300.0720.100 0.250.270.0860.155 0.1750.0780.240.250.088 0.21 0.230.074 0.1350.1500.071 0.1600.1700.0680.23 0.248000.056 -0.0720.150 0.1700.0640.240.25 -0.062 0.1300.1450.059 0.1550.1650.0550.230.2410000.045 -0.0630.150 0.1650.0540.240.24 -0.955 0.1300.1400.050 0.1550.1650.0470.23 0.2400 t Spacinglargerthanthosespecifiedin Method12(seeAnnexA, SectionB) will resultin largervoltagedrop'-ooCurrent-carryingcapacity(Amperes):TableB.11 .Multicore,non-armouroocablehavingthermosettinginsulation(copper conductors)Ambienttemperature:30'CConductor operatingtemperature:90'CReferenceMethod4 (enclosedinanReferenceMethod3 (enclosedin ReferenceMethod11 (on ainsulatedwall,etc.)conduiton a wallor ceiling, or inReferenceMethod1 (clippeddirect)perforatedcabletray)or ReferenceConductortrunking)Method13 (freeair)Cross-1 three-or1 two-core 1 two-core1 two-coreSectionalarea1 two-corecablefour-corecablecablesingle-1 three-or four-cablesingle-1 three-or four-cablesingle-1 three-orfour-single-phasea.c.corecablethree-core cablethree-corecablethree-or d.c.three-phasephasea.c.orphasea.c.phasea.c. orphasea.c.phasea.c.phasea.c.a.c.d.c. d.c.or d.c.1234 56789mm2AAA AAAAA1676689180~ 107 9611510025998911910513811914912735121109146128171147185158501451301751542091792251927018316422119426922928924695220197265233328278352298120.253227305268382322410346150290259334300441371473399185329295384340506424542456240386346459398599500641538300442396532455693576741621400--625536803667865741Note: (i) Wheretheconductoris to be protectedby a semi-enclosedfuse,seeA.6.2of thePrefaceto theAnnex.(ii) Wherea conductoroperatesata temperatureexceeding70C,it shallbe ascertainedthattheequipmentconnectedto theconductoris suitablefor theconductoroperatingtemperature.SECTION 4: CONDUCTORSTable B.12 Voltage Drop(per ampere per metre)Conductor operating temperature : 90CConductorTwo-core cableTwo-core cable single-Three-or four-core cablecross- sectional d.c.phase a.c.three-phase a.c.area12 3 4mm2mVmV mV162.9 2.92.5rxzr xz251.851.850.1601.901.600:1401.65351.351.350.1551.351.150.1351.15500.980.990.1551.000.860.1350.87700.670.670.1500.690.590.1300.60950.490.500.1500.520.430.1300.451200.390.400.1450.420.340.1300.371500.310.320.1450.350.280.1250.301850.250.260.1450.290.220.1250.262400.1950.2000.1400.240.1750.1250.213000.1550.1600.1400.210.1400.1200.1854000.1200.1300.1450.1950.1150.1250.170ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 101.....otvTable B.13 Single-corecableshavingthermosettinginsulation, non-magneticarmour(copperconductors)Current-carrying.capacity(Amperes): Ambienttemperature:30'cConductoroperatingtemperature:90'CReference Method 1Reference Method 11(onReference Method 12 (free air)(clipped direct)a perforated cable tray)2 caOJes,Conductor single-3 or 4 3 or 42 cables single-phase2 cables,2 cables d.c.3 or 4 cables, three-phase a.c.cross- phase a.c.cables, cablesa.c.sectional or d.c. flatthree-single-three-areaandphase a.c.phase a.c.phase a.c.touchingflat &or d.c. flatflat &HorizontalVertical flatHorizontalVerticalHorizontalVertical flattouching& touchingtouchingflat spacedspacedspacedspacedflat spacedspaced3 cables trefoil123456769101112mm2AAAAAAAAAA A50237220253232282266284270288266222703032773222933573:J735634935833128595,36733338935243641244642642539334612042538344940550447751949748544940215048843751646256653960057554951046318555749658752464361468866061857452924065657968961274971481578271566662530075566279270084280594390681075572040085371789976792988911371094848797815500962791101685110329891314126692387191863010828611146935113910921528147499294010278001170904124698712041155180917441042978111910001261961134510551289123821002026111010411214Note: (i) Wheretheconductoris to beprotectedbya seini-enclosedfuse,seeA.6.2of thePrefaceto thisAnnex.(ii) Whereaconductoroperatesata temperatureexceeding7Cf'C, it shallbeascertainedtbattheequipmentconnectedto theconductoris suitablefortheconductoroperatingt.empera'turc.TableB.14 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:90'C./-2 cables - single-phase a.c.3 or 4 cables - three-phase a.c.Conductor cross-2 cables d.c. Reference Methods 1.sectional area Reference Methods 1Reference Method 12 Reference Methods 1Reference Method .and 11 (Touching)(Spacedt)11 and 12 (in trefoiland 11 (Flat touching)12( Flat spaced t)..touching)1234567mm2mVmVmVmVmVmVrxz rxzr xzr xzrxz500.980.990.211.000.980.291.000.860.1800.870.840.250.880.840.330.90700.670.680.2000.710.690.290.750.590.1700.620.600.250.650.620.320.70950.490.510.1950.550.530.280.600.440.1700.470.460.240.520.490.310.580.39.0.410.1900.450.430.270.510.350.1650.390.380.240.440.410.300.511201500.310.330.1850.380.360.270.450.290.1600.330.310.230.390.340.290.451850.250.270.1850.330.300.260.400.230.1600.280.260.230.340.290.290.412400.1950.210.1800.280.240.260.350.1800.1550.240.210.220.300.240.280.373000.1550.1700.1750.250.1950.250.3201450.1500.210.1700.220.280.200.270.344000.1150.1450.1700.220.1800.240.300.1250.1500.1950.1600.210.270.200.270.335000.0930.1250.1700.210.1650.240.290.1050.1450.1800.1450.200.250.1900.240.316300.0730.1050.1650.1950.1500.230.270.0920.1450.1700.1350.1950.240.1750.230.298000.0560.0900.1600.1900.1450.230.270.0860.1400.1650.1300.1800.230.1750.1950.2610000.0450.0920.1550.1800.1400.210.250.0800.1350.1550.1250.1700.210.1650.1800.24t Spacingslargerthanthosespecifiedin Method12(seeAnnexA, Section8)will resultin largervoltagedrop.ELECTRICAL INSTALLATION OF BUILDINGSTableB.1S Multicorearmouredcableshavingthermosettinginsulation(copperconductors)Current-CarryingCapacity(Amperes): Ambient temperature: 30CConductoroperatingtemperature:90CReference Method 11 (onReference Method 1 (clipped direct)perforated horizontal or verticalcable tray}or Reference Method 13Conductor cross-(free air)sectional area1 two-core 1 two-corecable, single-1 three-or fourcable, single-1 three-or four-core cable,core cable,phase a.c. or three-phase a.c.phase a.c. orthree-phase a.c.d.c.d.c.12345mm2AAAASECTION 4: CONDUCTORSTableB.16 Voltagedrop(peramperepermeter)Conductoroperatingtemperature:90CConductorcross-Two-core CableTwo-core cable single-Three-or four-core cablesectionald.c.phase a.c.three-phase a.c.area12 3 4mm2mV mV mV1.531 31 272.519 19 16412 12 1067.9 7.9 6.8104.7 4.7 4.0162.9 2.9 2.5rx zrx z251.851.850.1601.901.600.1401.6535,1.351.350.1551.351.151.1351.15500.980.990.1551.000.860.1350.87700.670.670.1500.690.590.1300.60950.490.500.1500.520.430.1300.451200.390.400.1450.420.340.1300.371500.310.320.1450.350.280.1250.301850.250.260.1450.290.220.1250.262400.1950.200.1400.240.1750.1250.213000.1550.16'0.1400.210.1400.1200.1854000.1200.130.1450.1950.1150.1250.170ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 105/TableB.1? Ssingle-corenon-armouredcableshaving8SoC rubberinsulation(copperconductors)Current-carryingcapacity(Amperes): Ambienttemperature:30CConductoroperatingtemperature:85CReference Method 3 (enclosed inReference Method 1(clipped direct)Reference Method 11(on a perforatedReference Method 12 (free air)conduit, etc. in or on a wall)cable tray)Horizontal or VerticalConductorsingle-phase ac.Cross-3 or 4 cablesor d.c. or 3 or 4sectional 2 cable single-3 or 4 cables2 cables, single-three-phase ac.2 cables, single3 or 4 cables, three-cables three-3 cables trefoil three-phasearea phase ac. or d.c.three- phase ac.phase ac. or d.c.flat and touchingphase ac. or d.c.phase ac. flat andphase ac. flatac.flat and touching or trefoilflat and touchingtouching or trefoilspaced horizontalor vertical12 345678 9mm2A AAAAAA A117 151917.5--- -1.52219.52523--- -2.530 273431--- -440 364542--- -652 465954--- -1072 638175. --- -1696 85108100--- -2512711214313315314015413435157138177164189174192167501901672151992292112352047024221327425429326930326295293258332308356327370320120339298384357412379431373150372334442411475437499432185428379519469542499573495240510443607553639589679587300593506695636735679786680400719602827755860798929799500835689946865989918108191963097579110889961143106212631060Note:(i) Wheretheconduc~oris to beprotectedbya semi-enclosedfuse,seeA.6.2 oft thePrefacetoAnnex..(ii) Whereaconductoroperatesata temperatureexceeding70'C,it shallbeascertainedthattheequipmentcottnectedto theconductoris suitablefor theconductoroperatingtemperature.TableB.18 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:85Ct2 cables- single-phaseac. 3 or 4 cables- three-phaseac.Conductor2crosscablesReferenceMethodReferenceMethods1ReferenceMethodReferenceMethodsReferenceMethods1sectionald.c.3(Enclosedin conduitand 11 (clippedReferenceM~hod 123(Enclosedin conduit1,11, and 12(inand 11 (Flat. ReferenceMeth~ 12etc.inor on a walldirectorOn trays,Spaced )etc. in or on a wall)trefoiltouching)touching)(Flatspaced )touching)12 3 456789mm2mVmV mVmVmVmVmVmV146 46 46-404040-1.531 31 31-262626-2.518 18 18-161616-412 12 12-101010-67.7 7.7 7.7-6.76.76.7-104.6 4.6 4.6-4.04.04.0-162.9 2.9 2.9-2.52.52.5.rxz rxz rxz rxz rx z rxz rxz251.801.85 0.32 1.901.85 0.201.851.850.291.851.600.281.651.60 0.1751.601.60 0.251.601.600.321.65351.301.35 0.31 1.401.30 0.1951.351.300.281.351.150.271.201.15 0.1701.151.150.241.151.150.321.20500.951.00 0.30 1.050.97 0.190 0.990.970.281.000.870.260.910.84 0.165 0.860.840.240.880.840.320.90700.650.68 0.29 0.740.66 0.1850.690.660.270.720.600.250.650.57 0.160 0.600.57 0.240.620.570.310.65950.480.510.28 0.58 0.49 0.180 0.520.490.270.560.440.250.510.43 0.155 0.450.430.230.480.420.310.521200.380.40 0.27 0.490.390.175 0.430.390.260.470.350.240.430.340.1550.370.340.230.410.340.300.451500.300.33 0.27 0.420.310.175 0.360.310.260.400.290.240.370.27 0.150 0.310.27 0.230.350.270.300.401850.250.27 0.27 0.380.250.170 0.300.250.260.360.230.230.330.22 0.150 0.260.22 0.220.310.220.300.372400.1900.210.26 0.33 0.195 0.165 0.260.1950.250.320.180 0.230.290.170 0.145 0.220.170 0.220.280.170 0.300.343000.1500.170 0.26 0.310.155 0.165 0.230.1550.250.290.150 0.230.270.135 0.140 0.1950.135 0.220.26 .0.135 0.290.324000.1150.140 0.26 0.300.125 0.160 0.200.120 0.250.280.130 0.220.260.110 0.140 0.1750.110 0.210.240.105 0.290.315000.0910.115 0.26 0.280.100 0.155 0.1850.097 0.240.260.1050.220.240.089 0.135 0.1650.089 0.210.230.0850.290.306300.0720.100 0.25 0.270.082 0.155 0.1750.0770.240.250.0850.220.240.073 0.1350.1550.073 0.210.220.067 0.280.29Spacingslargerthanthosespecifiedin Method12(seeAnnexA of Section8) will resultin largervoltagedrop.....o00TableB.19 Multicore,sheathedandnon-armouredcableshaving85Crubberinsulation(copperconductors)Current-carryingcapacity(Amperes):Ambienttemperature:300CConductoroperatingtemperature:85CReference Method 3 (enclosed)Reference Method 1 (clipped direct)Reference Method 11 (on a perforated cable tray). orConductor cross-Refrence Metthod 13 (free air)sectional area1 two-core cable single-1 three- or four-core1 two-core cable. single-1 three- or four-core1 two-core cable single-1 three- or four-core cable. three..phase ac. or d.c.cable. phase ac.phase ac. or d.c.cable. three-phase ac.phase ac. or d.c.phase ac.12 3456 7mm2AAAAA A16.514.5181619.5 17.51.52118.5232025 222.52925322834 30438 33433746 40648 43554859 52106658766681 711687n10388109 9425114100136117144 12335139122168144In15150167147201174213 18670211185256222272 23795254222310269329 287120292256I359 312381I333150320287413;359438 383185368326I470 409J499 437240439381I553 482587 5153005094361636 555675593. INote: (i)(ii)Wheretheconductoris tobeprotectedbya semi-enclosedfuse.se{,A.6.2of thePrefaceto thisAnnex.Wherea conductoroperatesata temperatureexceeding70DC,it shallbeascertainedthattheequipmentconnectedto theconductoris suitablefor theconductoroperatingtemperature.SECTION 4: CONDUCTORSTable B.20 Voltagedrop (peramperepermeter)Conductoroperatingtemperatures:85CConductorTwo-core Three- or four-core, cable three-cross- sectional cable d.c.Two-core cable single-phase a.c.phase a.c.area12 3 4mm2mV mV mV146 46 401.531 31 262.5, 19 19 16412 12 1067.7 7.7 6.7104.6 4.6 4.0162.9 2.9 2.5rxzr xz251.801.850.1751.851.600.1501.60351.301.300.1701.351.150.1501.15500.950.970.1700.990.840.1450.86700.650.660.1650.680.580.1400.59950.480.490.1600.520.430.1400.451200.380.390.1600.420.340.1350.361500.300.310.1550.350.270.1350.301850.250.250.1550.300.220.1300.262400.1900.1950.1500.250.1700.1300.223000.1500.1550.1500.220.1350.1300.185ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 109..ELECTRICAL INSTALLATION OF BUILDINGSTable B.2l 60Crubber-insulatedflexiblecables,other than flexiblecordsCurrent-carryingcapacity:Ambienttemperature:30C(Amperes):Conductoroperatingtemperature:60'CConductorSingle-phase a.c. or d.c.Three-phase a.c.Single phase a.c. or d.c.cross- sectional1 two-core cable with or1 three-core, four-core orarea without protective conductorfive- core cable2 single core cables12 34mm2A AA430 26-639 34-1051 47-1673 63-2597 83-35- 10214050- 12417570- 15821695- 192258120- 222302150- 255347185- 291394240-,.343 471300- 394541400- .644500- -738630- .861Notes: (i) The tabulatedcurrentratingsareforcablesin freeair,butmayalsobeusedforcablesrestingona surface.If thecableistowoundonadrumonload,theratingsshouldbereducedin accordancewith(iii) belowand,for cableswhichmaybecovered,(iv)below.(ii) Wheretheconductoris to beprotectedbya semi-enclosedfuse,seeA.6.2of theprefaceto thisAnnex.(iii) The currentratingsof cablesusedonreelingdrumsaretobereducedbythefollowingfactors:a) Radialtypedrum i)ii)ventilated:85%unventilated:75%b) Ventilatedcylindricaltypedrum i) 1 layercable:85%ii) 2 layersof cable:65%iii) 3 layersof cable:45%iv) 9 layersof cable:35%A radial-typedrumisonewherespirallayersofcableareaccommodatedbetweencloselyspacedflanges;if fittedwithsolidflanges,theratingsgivenaboveshouldbereducedandthedrumis describedasnon-ventilated,andiftheflangeshavesuitableaperturesasventilated.A ventilatedcylindricalcabledrumisonewherelayersofcableareaccommodatedbetweenwidelyspacedflangesandthedrumandendflangeshavesuitableventilatingapertures.(iv) Wherecablemaybecoveredoveror coiledupwhilstonload,or theairmovementoverthecablerestricted,thecurrentratingshouldbereduced.It is notpossibletospecifytheamountof reduction;butthetableof ratingfactorsfor reelingdrumscanbeusedasa guide.110 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDTableB.22 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:60'CtConductor2 single-core cables touchingcross-Two-coreTwo-core cable single-phase1 three-core, four-core or five-coresectionalcable d.c. a.c.cable three-phase a.~Single-phase a.c.taread.c.mm2mV mV mVmVmV412 12 10--67.8 7.8 6.7--104.6 4.6 4.0--162.9 2.9 2.5--rxzr xz rxz251.801.800.1751.851.55 0.1501.55'- ---35- -1.100.1501.151.311.310.211.3250- -0.830.1450.840.910.910.210.9370- -0.570.1400.580.640.640.200.6795- -0.420.1350.440.490.490.1950.53120- -0.330.1350.360.380.380.1900.43150- -0.270.1300.300.310.310.1900.36185- -0.220.1300.260.250.250.1900.32240- -0.1700.1300.210.1900.1950.1850.27300- -0.1350.1250.1850.1500.1550.1800.24400- ---- 0.1150.1200.1750.21500- ---- 0.0900.0990.1700.20630- ---- 0.0680.0790.1700.185Largervoltagedropwill resultif thecablesarespaced.ELECTRICAL INSTALLATION OF BUILDINGSTable B.23 8SC or lS0C rubber-insulatedflexiblecablesCurrent-carryingcapacity(Amperes): Ambient temperature:30CConductoroperatingtemperature:85Cdc. or sing/I-phasla.c.Conductorcross-(1 two-corscable,withThrel-phasla.c.(1 thrsl-Singlephasl a.c.or dc. 2slctiona/areaor withoutprotlctivscors,four-corsor five-sing/I-corscablesconductor)corscable}touching12 34mnfA AA441 36653 471073 641699 862513111435140192501702407021629795262354.120303414150348476185397540240467645300537 74140088550010176301190CORRECTION FACTOR FOR AMBIENT TEMPERATURE85C rubber-insulatedcables:AmbientTemperature(0C): 35 40 45 50 55 60 65 70 75 80Correction factor: 0.95 0.90 0.85 0.80 0.74 0.67 0.60 0.52 0.43 0.30150Crubber-insulatedcables:AmbientTemperature(0e)Correction factor:AmbientTemperature(0e):Correction factor:35to 85 90 95 100 105 110 115t 120t 125t 130135t1.00 0.96 0.92 0.88 0.83 0.78 0.73 0.68 0.62 0.55 0.48140t 1450.39 0.28t Refer to notesfor Table B.2!.112 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDTable B.24 Voltage drop (per ampereper meter)Conductor operatingtemperature:85'CConductor1 two-coreor single-coreTwo-core cable single-phase1 three-core,four-core or flve-2 single-corecables touchingcross-sectional cables d.c.a.c.core cable three-phasea.c.Single-phasea.c.tarea12 3 45mm2mV mVmVmV413 13 11-68.4 8.47.3-105.0 5.04.3-163.1 3.12.7rx zr x zr xz252.02.000.1752.001.700.1501.70- --351.42 -1.200.1501.201.42 0.211.43500.99 -0.900.1450.910.99 0.211.01700.70 -0.610.1400.630.70 0.200.72950.53 -0.460.1350.480.53 0.1950.561200.41 -0.360.1350.390.41 0.1900.461500.33 -0.290.1300.320.33 0.1900.381850.27 -0.240.1300.270.27 0.1900.332400.21 -0.1850.1300.220.21 0.1850.283000.165 -0.1450.1250.1950.170 0.1800.254000.125 --- -0.130 0.1750.225000.098 --- -0.105 0.1700.206300.073 --- -0.084 0.1700.190Note:(i) Thevoltagedropfiguresgivenabovearebasedon a conductoroperatingtemperatureof 85Candare,therefore,notaccuratewhentheoperatingtemperatureisin excessof 85C.In thecaseof the15ELECTRICAL INSTALLATION OF BUILDINGSTable B.25 Current-carrying capacity [Amperes](fleXIblecords)Conductor cross-Current-carrying capacityMaximum masssupportable bysectional area Single-phase a.c.Three-phase a.c.twin flexible cord1234mm2AAkg0.53320.756631101051.2513-51.5161652.525205432255Where cableis on a reel,seenotesto Table B.21.CORRECTION FACTOR FOR AMBIENT TEMPERATURE60Crubber and p.Y.c.cords:AmbientTemperature(0C):Correction factor:35 40 45 50 550.91 0.82 0.71 0.58 0.4185Crubbercordshavingah.oJ.r. sheathoraheat-resistingp.Y.c.sheathandfor85Cheat-resistingp.Y.c.cords:AmbientTemperature(0C):35to 50 55 60 65 70Correction factor: 1.00 0.96 0.83 0.67 0.47ISOOCrubber cords:AmbientTemperature(C):35to 120125130135140145Correction factor:1.000.960.850.740.600.42Glass'fiber cords:AmbientTemperature(C):35to 150155160165170175Correction factor:1.000.920.820.710.570.40114 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 4: CONDUCTORSTableB.26 Voltagedrop (peramperepermetre)Conductoroperatingtemperature:600CtConductor cross- d.c.or single-phase a.c.Three-phase a.c.sectional area123mm2mVmV0.5093800.7562'541.0046401.2537-1.50 322:72.501910 .4.001218The tabulatedyaluesarefor 60'C rubber-insulatedandp.y.c.-insulatedflexiblecords.For othertypesof..flexiblecords,theyareto be multipliedbythefollowingfactors:For 85C rubberor p.y.c.-insulated:1.09150'Crubber-insulated: 1.31185Cglassfibre: 1.43ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 115TableB.27 Mineral insulatedcablesbareandexposedtotouch(seeNoteii below)or havingoverallcoveringof P.V.C.(copperconductorsandsheath)Current-carryingcapacity(Amperes):ReferenceMethod1 (OippedDirect)Ambienttemperature:30CSheathoperatingtemperature:70C2 single core3 single-core3 single-corecables or 1cables in 1 four-core 1 nineteen-Conductor two-coretrefolleor 1cables in flatcable 3 cores1 four-core1 seven-core1 twelve-corecore cablecross-sectional . cable, single-three-coreformation,loaded three-cable all corescable allcable all coresall coresarea . phasea.c. orcable, three-three-phasephase a.c.loadedcores loadedloadedloadedd.c.phase a.c.a.c.123456789mm2AAAAAAAALightduty,500V118.51517151310--1.5 23192119.516.513--2.5 312629262217.5--4 403538-----Heavy duty. 750V119.5161816.514.511.59.58.51.5 252123211814.512.010.02.5342831282519.516.0-4 453741373226--'6 5748524741---10 7765706455---16 10286928572---2513311212011094---35 163137147-----50 202169181-----70 247207221-----95 296249264-----120340286303-----150 388327346- .----185 440371392-----240 514434457-----Note: i) For single-corecables.thesheathsof thecircuitareassumedto be connectedtogetheratbothends.n_ - - hloe.~cx-r.c>''.cd1-~1-c->'L.'.. 1-he:;; tnhl...:llr.tec::1 ...al'U1cs. ,..h~,-'Id be>m .It.iplie.;:.l nv 0.9_''.-.t:le:B-27 lVIineralins&.alat:.edcablesbare a..d.exposedto to&.ach(seeNote ii bela,',>or havi..g overall coveri..g or p.v.c.(copperconductorsandsheath) (conte'd)Current-carryingcapacity(Amperes):ReferenceMethod11(On a perforatedcabletray,horizontalor vertical)AmbienttemperaPire:3O-CSheathoperatingtemperature:70C2 single-1 two-1core1 three-1 four-core1 four-1 seven-1 twelve-nineteen-3 single - core cables three-phase a.c..cablescorecable 3cablescore corecorecoretouchingcable,loadedcable allcable allcable allcoreConductor cable allcross- sectionalthree-three-phasecorescorescoresSingle phase a.c. or phase a.c.loadedloadedloadedcoresVerticalHorizontaFlatareaa.c.loadedTrefoild.c. spaceI spacedtouching101112131415161718192021mm2AAAAAAAAAAAAUght duty,500V1.018.519.516.5161411--19221716.51.5242521211814--252822212.5313328282419--323729'284.0424437-----43483937Heavy duty, 750V1202117.518161210921241917.51.5252622232015.51311273025222.534363030272117-354132304454740403528--4753434065760515144---59675451107882696859---8090736916104109928978---105119979225135142120116101---13515412512035165174147-----16418715314750204215182-----20223018818270251264223-----24627922922395301317267-----294333275267120346364308-----335382314308150395416352-----380431358352185448472399--..- --424482405399240524552466-----472537471466Note: i) For single-corecables,thesheathsof thecircuitareassumedtobeconnectedtogetheratbothends.ii) For barecableexposedto touch,thetabulatedvaluesshouldbemultipliedby0.9.....10TableDol7 Mineral insulatedcablesbareandexposedtotouch(seenote2) or havingoverallcoveringof P.V.C(copperconductorsandsheath)(conte'd)Current-carryingcapacity(Amperes):ReferenceMethods12and13(Freeair)Ambienttemperature:3O'CSheathoperatingtemperature:7DC3 single-core3 single-corecables three-2 single- corecables in trefoilor1 four-core1 four-core1 seven-1 twelve-1 nineteen-phase a.c.Conductorcables or 1 two-1 threecorecable 3 corescable allcore cablecore cablecore cablecore cable,single cable, three-loaded three-coresall coresall coresall coresVerticalHorizontTouchincross-phase a.c. or d.c. phase a.c.loadedloadedloadedload alsectionalarea phase a.c. spacedspaced922232425262728293031mm2AAAAAAIA AAAILight duty 500V119.516.5161411--2023181.52521211814--2629232.53328282419--34393144437-----455141Heavy duty, 750V1.02117.51816121092225201.52622232015.513113232262.5363030272117-37433444740I40 3528--495645660515144---6271571082696859---84957716109928978---11012510225142120116101---14216213235174147-----17319716150215182-----21324219870264223--.--25929424195317267-----309351289120.364 308-----353402331150416352-----40045,4-377185472399--.- --446507426240552466-----497565496Note_' i) For ~in_gle-c?~e_~~ble~~~',s?..=:,-~s.~'O~ ~ ~_~~c::';~~~~~'~~~~~dt~~..-..a~::~:::~~~~g~t:Peratbothends.SECTION 4: CONDUCTORSTableB.28 Mineral insulatedcablesbareandexposedtotouchor havinganoverallcoveringof p.v.c(copperconductorsandsheath)Voltagedrop(peramperepermeter)for single-phaseoperationsheathoperatingtemperature:70C.Conductorcross-sectional Two single-core cables,Multicore cablesareaTouching123--mm2 mVmV142421.528282.5171'141010677104.24.2162.62.6rxzr xz251.650.2001.651.650.1451.65351.200.1951.20---50 0.890.1850.91---70 0.620.1800.64---95 0.460.1750.49---1200.370.1700.41---150 0.300.1700.34---185 0.250.1650.29---240 0.1900.1600.25---ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 119ELECTRICAL INSTALLATION OF BUILDINGSTableB.28 Mineralinsulatedcablesbareandexposedtotouchor havinganoverallcoveringof p.v.c(copperconductorsandsheath)(conte'd)Voltagedrop(peramperepermeter)for single-phaseoperationsheathoperatingtemperature:70CConductorThree single-core cablescross-Flat formationMulticoresectionalTrefoil, touchingcablesareaTouching.Spaced 1cablediameterapart12 345mm2mVmVmVmV1.0363636361.524 -2424242.51414141449.19.19.19.166.06.06.06.0103.63.63.63.6162.32.32.32.3rx z rxz rxzrxz251.450.1701.451.450.251.451.45 0.321.501.600.1251.60351.050.1651.051.050.241.101.050.311.10---500.780.1600.800.790.240.830.82 0.310.87---~o0.540.1550.560.550.230.600.58 0.300.65---950.400.1500.430.410.220.470.44 0.290.53---1200.320.1500.360.330.220.400.36 0.280.46---1500.260.1450.300.290.210.360.32 0.270.42---1850.210.1400.260.250.210.320.28 0.260.39---2400.1650.1400.220.210.200.290.26 0.250.36---120 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDAmbient temperature:30'CSheathoperatingtemperature:105CTableB.29 Mineral insulatedcablesbareandneitherexposedtotouchnor in contact'th comhustiblematerials(copperconductorsand sheath)Current-carryingcapacity(Amperes):ReferenceMethod 1 (Oipped Direct)2 single core3 single-core3 single-coreConductorcables or 1cables in 1 four-coretwo-coretrefoil or 1cables in flatcable 3 cores,1 four-core1 seven-core1 twelve-core1 nineteen-'cross- formation,cable, allcable all corescable all corescore cable allsectional cable, single-three-corethree-phaseloaded three-cores loadedloadedloadedcores loaded'area phase a.c. orcable, three- phase a.c.d.c.phase a.c.a.c.123456789mm2AAAAAAAALightduty,500V1.022192118.516.513--1.5 282427242116.5--2.5 383336332822--4.0 514447-----H~vy duty,750V10.51.0 2420242017.514121.5 31263026'2217.515.5132.5 42354135302420-4 554753464032--6 7059675850---16 12710711910390---25 166140154134117---35 203171187-----50 251212230-----70 307260280-----95 369312334-----120 424359383-----150 485410435-----185 550465492-----240 643544572-----'Vote: I) 1'orSln~e-corecables.thesheathsot thecIrCUItareassumedto be connecteatOQetnerat botnends.ii) No correctionfactorfor groupingneedbe applied.iii) Whereaconductoroperatesatatemperatureexceeding7ffcit shallbeascertainedthattheequipmentconnectedtotheconductorissuitablefortheconductoroperatingtemperature.....tvtvTableB.29 Mineral insulatedcablesbareandneitherexposedto touchnor in contactwithcombustiblematerials(copperconductorsandsheath)(conte'd)Current-carryingcapacity(Amperes):ReferenceMethods12and13(Freeair)Ambienttemperature:30'CSheathoperatingtemperature:105'?C2 single-3 single-3 single-core cables three-phasecore core1 four-corecables or 1cables incable 31 four-core1 seven-1 twelve-1 nineteen- a.c.Conductor two-coretrefoil or 1corescable allcore cablecore cablecore cablecross- cable,three-coreloadedcoresall coresall coresall coressectional single-cable,three-loadedloadedloadedloadedVerticalHorizontalarea phase a.c.three-phase a.c.. spacedspacedTouchingor d.c.phase a.c.10111213141516171819mm2AAAAAAAAAALightduty,500V1.02421201814--2629231.53126262218--3337292.54135353024--4349394.05446-----566451Heavyduty,750V1262222191513112832251.5332828241916.5143540322.5453837322622-47544346050494334--617056676646354---78897110 104878573---105120961613711511297---13715712725179150146126---17820416435220184-----21624820050272228-----26630424770333279-----32337030095400335-----385441359120460385-----441505411150526441-----498565469185.557629530596 500-----240 697584-----624704617Note: ])For S1n21e-corecables,thesheaths01theCIrcUItareassumedto beconnectedtOQetler at bothends.ii) No correctionfactorfor groupingneedbe applied.iii) Wherea conductoroperatesat a temperatureexceeding7Cf'C. it shallbe asce:1:ainedthattheequipmentconnectedto theconductoris suitablefor theconductorope...at.inp::temporat.-ure.SECTION 4: CONDUCTORSTableB.30 Mineralinsulatedcables,bareandneitherexposedto touchnor in contactwithcombustiblematerials(copperconductorsandsheath)Voltagedrop(peramperepermetre)for single-phaseoperationSheathOperatingTemperature:105CConductorTwo single-core cablescross-sectionalMulticore cablesareaTouching12 3mm2A A1.047 471.531 312.519 19412 12- 6 7.8 7.8104.7 4.7163.0~i. 3.0rx zrxz251.850.180,1.85 1.850.1451.85351.350.175 1.35---501.000.170 1.00---700.690.165 0.71---950.510.160 0.54---1200.410.160 0.44---1500.330.155 0.36---1850.270.150 0.31---2400.210.150 0.26---ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 123ELECTRICAL INSTALLATION OF BUILDINGSTableB.30 Mineralinsulatedcables,bareandneitherexposedto touchnor in contactwithcombustiblematerials(conte'd)(copperconductorsandsheath)Voltagedrop(peramperepermetre)for single-phaseoperation: Sheathoperatingtemperature:105CThree single-core cablesConductorTrefoilFlat formationMulticorecross-sectionaltouchingcablesareaTouchingSpaced 1 cablediameterapart12345mm2mVmVmVmV1.0404040401.5272727272.51616161641010101066.86.86.86.810'4.14.14.14.1162.62.62.62.6rxzrxzrxz rxz251.60 0.160 1.651.60 0.23 1.651.60 0.31 1.651.60 0.125 1.60351.15 0.155 1.201.15 0.23 1.201.20 0.30 1.25-- -500.87 0.150 0.880.88 0.22 0.910.90 0.29 0.95-- -700.60 0.145 0.620.61 0.22 0.650.63 0.290.70-- -950.45 0.140 0.470.46 0.21 0.500.48 0.28 0.56-- -1200.36 0.135 0.380.37 0.21 0.420.39 0.28 0.48-- -1500.29 0.135 0.320.31 0.20 0.370.34 0.27 0.43-- -1850.23 0.130 0.270.26 0.20 0.330.29 0.26 0.39-- -2400.1800.1300.220.22 0.195 0.290.26 0.25 0.36-- -124 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDTableB.31 Single-coreP.V.C.-insulatedcables,non-a.oured,'..jthor withoutsheath(aluminiumconductors)Current-carryingcapacity(Amperes):Ambienttemperature:30CConductoroperatingtemperature:70CReference Method 4Reference Method 3Reference Method 11Reference Method 12 (free air)(enclosed in conduit in(enclosed in conduit onReference Method 1(on a perforated cabI -thermally insulatingwall a wall or in trunking etc.)(clipped direct)tray, horizontal orHorizontalVertical flatTrefoiletc.)vertical)flat spacedspacedConductor cross-2 cables,3 or 42 cables,3 or 42 cables,2 cablessectional 2 cables,3 or 42 cables,3 or 4single-cables,single-cables,thresingle-single-3 cablesarea single-cablessingle-cablesphase a.c.three-phase a.c.e-phasephase a.c.phase a.c.trefoilphase a.c.a.c. flator d.c. or 3or d.c. or 3phase a.c.three-phase a.c.three-or d.c. flatflat andor d.c. flatandcablescablesthree-or d.c.phase a.c.or d.c.phase a.c.andtouchingorandtouchingorthree-three-phase a.c.touchingtrefoiltouchingtrefoilphase a.c.phase a.c.123456789101112mm2AAAAAAAAAAA50938411B1041341231441321631481287011810715013317215918516921019116595142129181161210194225206256234203. 120 164149210186245226261240298273237150 189170234204283261301277344317274185 215194266230324299344317394364316240 252227312269384354407375466432375300 289261358306444410469433538501435380--413352511472543502625584507480--477405591546629582726680590600--545462679626722669837787680740----771709820761956902776960----900823953886112510669071200----10229261073999129312291026Nnte: Wheretheconductoristobeprotectedbyasemi-enclosedfuse,seeA.6.2ofthePrefacetothisAnnex.~~TableB.32 Voltagedrop(peramperepermeter)ConductorOperatingTe~perature:70'C2 c,bIes . singfe-p/llsea.c. 3 ' 4 c,bIes tJuee.(Jhasea.e.C,nduct/1,ReferenceMethods3 ReferenceMethods3crrmsectional2 C8bJesd~.,nd 4 (fndostJdinReferenceMethods 1ReferenceMethlJd 12and 4 {enclosedinReferenceMllthods 'ReferenceMiJtlllJds 1Referenc,M,thod 12,,. ctmduitetc. in If fin ,,nd 11{cippetldirectfI'{sp,c.!}Cflnduitetc. in II' fiR ,11 ,nd 12{IntreflJi,nd 11{FlattflUchingJIFIIt sp,c.!}rnIJfin tray$,tflUching}walltflUChing},1 J 45,7,I.',zmVmVmVmVmVmVowmV,xz, xz, xz,xz,AZ, XZ, xz5111.551.600.301.601.550.1901.551.550.28..1.551.350.261.401.350.1651.351.350.241.351.350.321.40701.051.100.301.151.050.1851.051.050.27-'.,00.940.260.970.910.1600.920.910.240.940.910.310.96950.770.81D.290.860.770.1850.790.770.270.820.700.250.740.670.1600.690.67D.230.710.670.310.741200.610.64D.290.700.610.18110.640.610.270.670.550.250.610.530.1550.550.530.230.580.530.310.6115110.490.510.280.590.490.1750.520.490.260.550.45D.240.510.420.1550.450.420.230,480.420.300.521850.390.42D.280.5110.400.1750.430.39D.260,470.36D.240.440.340.15110.370.340.230.410.340.300.462400.300.320.270.420.300.1700.350300.260.400.28D.240.370.260.15110.300.260.220.350.260.300.403000.240.260.270.370.240.1700.300.240.260.350.230.230.320.210.1450.260.210.220.310.210.300.3638110.190D.22D.270.350.1950.1650.260.1950.250.320.1900.230.300.1700.1450.220.1700.22D.280.1700.290.344800.15110.18110.260.320.1550.165D.230.1550.250.290.155 ' 0.230.270.1400.140 0.1950.1400.22D.260.1350.290.326000.1200.15110.270.310.1300.1600.210.125D.25D.280.1250.220.260.1100.140 0.18110.1100.220.240.1100.290.317400.099 0.1050.160 0.1900.100D.250.27. 0.0940.135 0.1650.0940.210.230.0890.290.3096IJ0.075 0.0860.155 0.18110.082D.240.26 0.0770.135 0.1550.0770.210.220.0710.290.2912oo0.060 0.0740.155 0.1700.0680.240.25 0.066 .0.135 0.15110.0660.21D.220.059 0.28D.29t Spacingslargerthanthosespecifiedin Method12(seeAnnexAnnexA of Section8)will resultin largervoltagedrop.TableB.33 MulticoreP.V.C,-insulatedcables,non-armoured(aluminiumconductors)Current-carryingcapacity(Amperes): Ambienttemperature:30CConductoroperatingtemperature:70CReference Method 4 (enclosed inReference Method 3 (enclosed inReference Method 1 (clippedReference Method 11 (on aconduit on a wall or ceiling, or inperforated cable tray), oran insulatingwall, etc.) trunking)direct)Reference Method 13 (free air)Conductor cross- sectional1 two-core1 three- or four-1 two-core1 three- or four-1 two-core,1 three- or four-1 two-core1 three- or four-areacable, single-corecable, single-core cablecable, single-core cable,cable, single-core cable,phase a.c. orcable,three-phase a.c. orthree-phase a.c. orthree-phasephase a.c.three-phased.c.phase a.c.d.c.phase a.c.d.c..a.c.or d.c.a.c.1234 56 789mm2AAAAAAAA16444154486659736125585371628373897835716586n103901119650867810492125110135117. 70 1089813111616014017315095130118157139195170210183120-135-160-197-212150-155-184-227-245185-176-210-259-280240-207-248-305-330300-237-285-351-381Note: Wheretheconductoris to beprotectedby a semi-enclosedfuse,seeA.6.2 of thePrefaceto thisAnnex.TableB.32 Voltagedrop(peramperepermeter)ConductorOperatingTe~perature:70'C2 cilbies . single-p/lIISBII.C. 3 II 4 cilbies . t!IrrJe.pMSBII.t.ClndUCtIJlReferenceMethtJds3 ReferenceMethtJds3Cf'(JssstlCtional2 ubles d.c.1Int14 (EndtJSIJdinReferenceMethlJds 1ReferenceMethIJd 12and 4 {endtJstJdinReferenceMethtJds'ReferenceMethods 1ReferenceMethtJd 1211mClJndtit etcy in IJf on II1Int111{tippeddirect01(spac.!)conduitetcy in bl In II1111nt112{TntrefrJiIInd 11(Flat tluclling)IFIIIt SPIIC.!)waI)In tny. tlUelling)WIIIJtouching)11 J 45,7,I- mVmVmVmVmVmVmrmVIxZI XZI XZI XZrAzI XZI Xz5/11.551.600.301.601.550.1901.551.55D.28.;1.551.350.261.401.350.1651.351.350.241.351.350.321.40701.051.100.301.151.050.1851.051.050.27'1.100.940.260.970.910.1600.920.910.240.940.910.310.96950.770.81D.290.860.770.1850.790.770.270.820.700.250.740.670.1600.690.670.230.710.670.310.741200.610.64D.290.700.610.1800.640.610.270.670.550.250.610.530.1550.550.53D.230.580.530.310.6115/10.490.510.280.590.490.1750.520.490.260.550.45D.240.510.420.1550.450.420.230.480.420.300.521850.390.42D.280.5/10.400.1750.430.39D.260.470.36D.240.440.340.15/10.370.340.230.410.340.300.462400.300.32D.270.420.300.170D.350300.260.40D.28D.240.370.260.15/10.300.260.220.350.260.300.403000.240.260.270.370.240.1700.300.240.260.350.230.230.320.210.1450.260.210.220.310.210.300.363800.1900.21D.270.350.1950.1650.260.1950.250.320.1900.230.300.1700.1450.220.1700.22D.280.1700.290.344800.15/10.1800.260.320.1550.1650.230.1550.250.290.155 /0.23D.270.1400.140 0.1950.1400.22D.260.1350.290.326000.1200.15/10.270.310.1300.1600.210.125D.25D.280.1250.22D.260.1100.140 0.1800.110D.220.240.1100.290.317400.099 0.1050.160 0.1900.100D.250.27. 0.0940.135 0.1650.094D.210.230.089D.290.309600.075 0.0860.155 0.1800.082D.240.26 0.0770.135 0.1550.0770.210.220.0710.290.2912000.060 0.0740.155 0.1700.0680.240.25 0.066 .0.135 0.15/10.0660.210.220.059 '0.280.29t Spacingslargerthanthosespecifiedin Method12(seeAnnexAnnexA of Section8)will resultin largervoltagedrop.TableB.33 MulticoreP.V.C,-insulatedcables,non-armoured(aluminiumconductors)Current-carryingcapacity(Amperes): Ambienttemperature:30CConductoroperatingtemperature:70CReference Method 4 {enclosedinReference Method 3 {enclosedinReference Method 1 {clippedReference Method 11 (on aconduit on a wall or ceiling, or inperforated cable tray), oran insulatingwall, etc.) trunking)direct)Reference Method 13 (free air)Conductor cross- sectional1 two-core1 three- or four-1 two-core1 three- or four-1 two-core,1 three- or four-1 two-core1 three- or four-areacable, single-corecable, single-core cablecable, single-core cable,cable, single-core cable,phase a.c. orcable,three-phase a.c. orthree-phase a.c. orthree-phasephase a.c.three-phased.c.phase a.c.d.c.phase a.c.d.c.. a.c.or d.c.a.c.1234 56 789mm2AAAAAAAA16444154486659736125585371628373897835716586n103901119650867810492125110135117. 70 1089813111616014017315095130118157139195170210183120-135-160-197-212150-155-184-227-245185-176-210-259-280240-207-248-305-330300-237-285-351-381Note: Wheretheconductoris to beprotectedby a semi-enclosedfuse,seeA.6.2 of thePrefaceto thisAnnex.ELECTRICAL INSTALLATION OF BUILDINGSTableB.34 Voltagedrop(peramperepermeter)Conductoroperatingtemperature:70CConductorcross-Two-coreTwo-core cable singe-Three-or four-core cable,sectionalcable d.c.phase a.c.three-phase a.c.area 12 3 4mm2mV mV mV164.5 4.5 3.9rxzr xz252.92.90.1752.92.50.1502.5352.12.10.1702.11.800.1501.80501.551.550.1701.551.350.1451.35701.051.050.1651.050.900.1400.92950.770.770.1600.790.670.1400.68,120- -0.530.1350.55150- -0.420.1350.44185- -0.340.1350.37240- -0.260.1300.30300- -0.210.1300.25rI128 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDCurrent-carryingcapacity(Amperes):TableB.35 Single-corearmouredP.V.C.-Insulatedcable,Non-magneticarmour.(aluminumconductors)Ambienttemperature:30'CConductoroperatingtemperature: 70'CReference Method 1Reference Method 11(clipped direct)(on a perforated cableReference Method 12 (free air)tray)Conductor cross2 cables3 or 42 cables3 or 4sectionalsingle-cablessingle-cables2 cables single-phase a.c.2 cables d.c. spaced3 or 4 cables, three-phase a.c.areaphase a.c.three-phasephase a.c.three-phaseor d.c. flator d.c. flatanda.c. flat andanda.c. flat andHorizontalVertical HorizontalVertical flat3 cablestouching-t1)uchingHorizontal- Verticaltouchingtouchingflat spacedflatspaced flat spacedspacedtrefoil12345,6789101112mm2AAAAAAAAAAA50143133152141168159167157169155131701831681941782122002142022131961689522120223421425924526124725523620512025523327024629928530328829327223815029426731028234032334933333531227518533430335231938937140038237935431524039335441337445743747245244341537230045240547442752049854552350547543038051845254347958355963861355151849748058650161653465562974271560456856860065855069258972469685982865661864274072859676964280277098695270766671596081965186870686683211711133770726808120089369295275693890213601317822774880~IV0 Note: Wheretheconductoristobe protectedby asemi-enclosedfuse,seeA.6.2of thePrefacetothisAnnex.TableB.36 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:70C2 cables, single-phase a.c.3 or 4 cables, three-phase a.c.Conductor:cross-2 cables d.c.Reference MethodsReference MethodReference MethodsReference MethodsReference Methodsectional area1 and 11 (Touching)12 (Spacedt)1,11 and 12 (In1 and 11 (Flat12 (Flat spacedt)trefoil touching)touching)123 4567mm2mVrY)VmVmVmVmVrxzr xzr xzr x zr xz501.551.550.231.551.550.311.551.350.1951.351.350.271.351.300.341.35701.051.050.221.101.050.301.100.920.1900.930.930.260.960.950.331.00950.770.780.210.810.810.290.860.680.1850.700.700.250.750.730.320.801200.610.620.210.660.650.290.710.540.1800.570.570.250.620.600.320.681500.490.500.200.540.530.280.600.440.1750.470.460.240.520.500.310.581850.390.410.1950.450.440.280.520.350.1700.390.380.240.450.420.300.512400.300.3~0.1900.370.340.270.440.280.1650.320.300.230.380.330.290.443000.240.260.1850.320.280.260.390.220.1600.270.240.230.340.280.290.403800.1900.220.1850.280.260.250.360.1850.1550.240.220.220.320.270.260.384800.1500.1800.180.250.220.250.330.1550.1550.220.1950.220.290.240.250.356000.1200.150.1750.230.1950.240.310.1300.150 0.2000.1700.210.270.210.240.327400.0970.1350.1700.220.1800.230.290.1150.1450.1850.1600.200.260.2000.220.309600.0750.1150.160 0.2000.1650.210.270.1000.1400.1750.1500.1850.240.1900.1950.2712000.0600.1100.155 0.1900.1600.1800.240.0940.1400.1700.1450.1600.220.1850.1650.25t Spacingslargerthanthosespecifiedin Method12(seeAnnexA, Section8 ) will resultin.a largervoltagedrop.SECTION 4: CONDUCTORSTableB.37 MulticorearmouredP.V.C.-insulatedcables(aluminiumconductors)Current-carryingcapacity(Amperes): Ambient temperature:30'CConductoroperatingtemperature:70'CConductorReference Method 1Reference Method 11cross-sectional(clipped direct)(on a perforatedcable tray)areaor Reference Method 13 (free air)1 two-core1 three- orcable, single-four-core1 two-core cable,1 three- or four-phase a.c. orcable, three-single-phase a.c.core cable, three-d.c.phase a.c.or d.c.phase a.c.123 4 5mm2AA A A166858 71 612589763594801099450131115997011313911916514395199175151174211186120-202150-216-232185-250-265240-287-312300-342-360 -399Note: Wheretheconductoris to beprotectedby a semi-enclosedfuse.seeA.6.2of thePrefaceto thisAnnex.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 131ELECTRICAL INSTALLATION OF BUILDINGSTableB.38 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:70CConductorcross-Two-core cableTwo-core cable single-Three- or four-core cable,sectionald.c.phase a.c.three-phase a.c.area112 3 4mm2mV mV mV164.5 4.5 3.9rxzr x z252.92.900.1752.902.50.1502.5352.12.100.1702.101.800.1501.80501.551.550.1701.551.350.1451.35701.051.050.1651.050.900.1400.92950.770.770.1600.790.670.1400.68~120- -0.530.1350.55150- -0.420.1350.44185- -0.316.1350.37240- -0.260.1300.30300- -0.210.1300.25132 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDAmbienttemperature:3O'CConductoroperatingtemperature:9{fC._~ ...~~ __ i tTable8.40 Voltagedrop(peramperepermeter)Conductoroperatingtemperature:WOe~.2 cables- single-phasea.c. . 3 or 4 cables - three-phasea.c.ConductorReferenceReference Refer~ncescross-2 cablesMethods3 and4Methods1 and Methods3 and4ReferenceReferencesectional d.c. ReferenceMethod ReferenceMethodarea(enclosedin11 (clippeddirect12 (Spacedt)(enclosedinMethods1. 11Methods1 and 1112 (flatspacedt)conduitetc. in oror on trays, conduit,etc or onand 12 (intrefoil)(flatandtouching)on a walltouching) a wall)12 3 45e789mm2mVmVmVmVmVmVmVmV--,rxzr xzr xzr xzr xzr xzr xz1.601.700.301.721.650.190 1.661.650.281.68.1.440.261.461.440.165 1.451.440.241.461.440.321.4850 1.131.170.301.211.120.185 1.141.120.271.151.000.261.040.970.1600.980.970.241.000.970.31 1.0870 0.820.860.290.910.820.185 0.840.620.270.940.750.250.790.710.1600.730.710.23 .0.570.710.31 0.78950.650.680.290.740.650.180 0.670.650.270~700.590.250.640.570.1550.590.570.230.610.570.31 0.64120 0.530.540.280.610.520.175 0.550.520.260.580.480.240.540.450.1550.470.450.230.500.450.30 0.54150 0.420.450.280.530.430.175 0.460.420.260.490.380.240.450:360.1500.390.360.230.430.360.30 0.47185 0.320.340.270.430.320.170 0.360.320.260.410.300.240.380280.1500.320.280.220.350.280.30 0.41240 0.260.280.270.380.260.170 0.310.260.260.360250.230.340220.1450.270.220.220.310.220.30 0.373000.20--- 0.21 0.165 0.270.210.25 0.330.200.230.310.180 0.145 0.230.180 0.220.280.1800.29 0.34380 0.160---0.1700.165 0.230.1650.250.300.165 0.230.280.150 0.140 0.200.150 0220.270.1450.29 0.32480 0.1300.1400.160 0.210.1350.250.280.135 0.220.260.120 0.1400.1650.120 0.22 0.250.1200.29 0.31- --600 0.105 0.1150.160 0.190.1100.250.27 0.100 0.1350.1700.100 0.21 0.230.0950.29 0.30- -- ---740 0.080 0.0920.155 0.180.0870.240.26 0.082 0.1350.1600.082 0.210.230.0760.29 0.30- -- ---9600.064---0.0790.155 0.170.073.240.25---0.070 0.1350.1500.070 0.210.220.0630.28 0.291200 -'~t Spacingslargerthanthosespecifiedin Method12(seeAnnexA of Section8) will resultin a largervoltagedrop.TablB~ ftIlItI_~8 1 non-ou..-(aluminiumconductors)Current-carryingcapacity(Amperes): Ambienttemperature:30'CConductoroperatingtemperature:9O'CReference Method 4 (enclosed.Reference Method 3 ( enclosedReference Method 1 (clippedReference Method 11 (on ain an insulated wall, etc.)in conduit on a wall or ceiling,direct)perforated cable tray), or Referenceor in trunking)Method 13 (free air)Conductorcross1 two-core1 three- or1 two-core1 three- or1 two-core1 three- or1 two-coresectional area cable,single-four-corecable, single-four-corecable,single-four-corecable,cable, single-1 thee- or four-phase a.c. or cable, three-phase a.c. orcable, three-phase a.c. orthree-pbasephase a.c. orcore cable,d.c. phase a.c.d.c.phase a.c.d.c.s.c.d.c.three.-phasea.c.123456789mm2AAAAAAAA16605572648476917725787194841019010897359687115103126112135120501151041381241541361641467014513117515619817421118795175157210188241211257227120-180-216-245 -2631,50-206-240-283 -304185-233-272-323 - .347240-273-318-382 -409300-313-364-440 -471Note: i) Wheretheconductoris tobeprotectedbya semi-enclosedfuse,seeA.62 of th' Prefaceto thisAnnex..ii) Wherea conductoroperatesatatemperatureexceeding7ffc, it shallbeascertainedthattheequipmentconnectedto theconductoris suitablefor theconductoroperatingtemperature.ELECIAICAlINSTALLATION OF BUILDINGSTableB.42 Voltagedrop(peramperepermetre)Conductoroperatingtemperature:90CConductor Three or four-core cable,cross-Two-core cableTwo-core cable single-three-phase a.c.sectionald.c.phase a.c.area12 3 4mm2mV mV mV164.8 4.8 4.2rx zr xz253.13.100.1653.102.70.1402.7352.22.200.1602.201.900.1401.95501.601.650.1601.651.400.1351.45701.101.100.1551.150.960.1350.97950.820.820.1500.840.710.1300.72120----0.56 0.1300.58150----0.45 0.1300.47185----0.37 0.1300.39240----0.28 0.1250.31300----0.23 0.1250.26136 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDTableD.43 Single-corecableshavingthermosettinginsulation,non-magneticarmour(aluminiumconductors)Current~carryingcapacity(Amperes): Ambient temperature:30CConductor operatingtemperature:900C/Reference Method 1Reference Method 11 (onReference method 12 (free air)(clipped direct)a perforated cable tray)Conduct2 cables,3 or 42 cables,3 or 4or cross- single-cables,singlecables2 cables single-phase Ii.C.2 cables d.c.3 or 4 cables, three-phase a.c.sectional phase a.c.three-phasephase a.c.three-phaseareaor d.c., flata.c., flator d.c., flata.c., flatandandandandHorizontalVertical flatHorizontalVerticalHorizontalVertical flat3 cablestouchingtouchingtouchingtouchingflat spacedspacedspacedspacedflat spacedspacedtrefoilmm2AAAAAAAAAAA501791651921762121992161972151921627022820924422226925427525327024420795276252294267328310332307324296252120320291340308378358384357372343292150368333390352429409441411424394337185419378444400490467511480477447391240494443521468576549605572554523465300568508597536654624701666626595540380655573688608735704812780639649625480747642786685825790942906765717714600836706880757909872107610368327808017409347649888249899501250120~8908358979601056838112191110941052148814359709111014120011639031236990118711411715165810439801118Note: i) Wheretheconductoris to beprotectedby a semi-enclosedfuse,seeA.6.2of thePrefaceto thisAnnex.ii) Wherea conductoroperatesata temperatureexceeding7rflC, it shallbe ascertainedthattheequipmentconnectedto theconductoris suitablefor theconductoroperatingtemperature.-l.H00TableB.44 Voltagedrop(per ampereper meter)Conductor operatingtemperature:9(fC2 Cables - single-phase a.c.3 or 4 cables - three-phase a.c.Conductor2 cablescross- d.c.Reference Methods 1Reference Method 12Reference Methods 1,Reference Methods 1Reference Method 12sectional areaand 11 (Touching)(Spaced1)- ,11 and 12 (In trefoiland 11 (Flat touching)(Flat spacedt)touching)mm2mVmV mVmVmVmVrxzr xzr xzr xzr xz501.601.600.221.601.600.301.601.400.1651.401.400.261.401.350.341.40701.101.100.210.151.100.291.150.960.1600.960.970.251.000.990.331.05950.620.630.200.650.650.290.900.710.1750.740.740.250.760.760.320.631200.660.660.200.690.690.260.740.570.1700.600.600.240.640.630.310.701500.520.530.1950.570.560.260.620.460.1700.490.490.240.540.520.300.601650.420.430.1900.470.460.270.540.360.1650.410.400.240.470.440.300.532400.320.340.1650.390.370.270.450.29.0.1600.340.320.230.390.350.290.463000.260.270.1650.330.300.260.400.240.1600.290.260.230.340.290.290.413600.210.230.1600.290.260.250.360.1950.1550.250.230.220.320.270.270.364600.1600.1850.1750.250.230.250.340.1600.1550.220.200.210.290.240.260.356000.1300.1600.1750.240.200.240.310.1350.1500.200.1750.210.270.220.250.337400.1050.1400.1700.220.1900.220.290.1200.1450.1900.1650.1950.260.210.220.309600.0800.1200.1600.200.1700.210.270.1050.1400.1750.1500.1600.240.1950.1950.2612000.0640.1050.1600.1900.1550,200.250.0930.1350.1650.1400.1750.220.1600.1650.26t Spacingslargerthantho~ specifiedin Method12(seeAnnexA. Section8)will resultlargervoltagedrop.SECTION 4: CONDUCTORSTableB.45 Multicorearmouredcableshavingthermosettinginsulation(aluminiumconductor)Current-carryingcapacity(Amperes): Ambient temperature:30CConductoroperatingtemperature:900CReference Method 11 (on a perforatedConductoReference Method 1 (clipped direct)cable tray) or Reference Method 13r cross-(free air)sectional1 two-core cable1 three- or four 1 three- or four-area single-phase a.c.core cable,1 two-core cable,core cable three-or d.c.three-phase a.c.single-phase a.c.phase a.c.12 345mm2A AAA1682 718574251'08921129835132 11313812050159 13716614570201 17421118595242 214254224120-249-264150-284-305185-328-356240-386.418300-441-488Note: i) Wheretheconductoris to beprotectedbyasemi-enclosedfuse,seeA.6.2of thePrefaceto thisAnnex.ii) Wherea'conductoroperatesat a temperatureexceeding7fYC, it shallbe ascertainedthattheequipmentconnectedto theconductoris suitablefor theconductoroperatingtemperature.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 139ELECTRICAL INSTALLATION OF BUILDINGSTableB.46 Voltagedrop (peramperepermetre)Conductoroperatingtemperature:90CConductor cross-Two-coreTwo-core cable single-Three or four-core cable,sectionalcable d.c.phase a.c.three-phase a.c.area 12 3 4mm2mV mV mV164.8 4.8 4.2rxzr xz253.13.10.1653.102..70.1402.7352.22.20.1602.201.900.1401.95501.601.650.1601.651.400.1351.45701.101.100.1551.150.960.1350.97950.820.820.1500.840.710.1300.72---120--- -0.560.1300.58150----0.450.1300.47185----0.370.1300.39240----0.280.1250.31300---.0.230.1250.26140 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 5EQUIPMENT5.1 SCOPE(1)This. Section covers services,serviceequjpment,and meteringequipmentand theirinstallationrequirementsfor systemsoperatingat 1000.OV or less.5.2 NORMATIVE REFERENCES(1)Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationof Buildings.(a) C22.1:1992 CanadianElectricalCodePart 1, SafetyStandardfor ElectricalInstallations,SixteenthEdition(b)NFPA 70/NEC:1986 NationalFireProtectionAssociation/AmericanNationalElectrical~ Code,1987Edition(c) IEE:19705.3 DEFINITIONSThe Institute of Electrical Engineers,Regulationsfor theElectrical Requirementsof Buildings, FourteenthEditionIncorporatingAmendments(1)For thepurposeof thisSection,in additionto thetermsdefinedin Section1,thefollowingdefmitionsshallapply.serviceconductors/ cable141 EBCS-10 1995thesupplyconductors/cablethatextendfromthestreetmainorfrom transformersto theserviceequipmentof theconsumer'sinstallation.ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSservicedrop theoverheadserviceconductorsfromthelastpoleor otheraerialsupportto andincludingthesplice, if any,connectingto theservice-entranceconductorsatthebuildingor otherstructure.service-entranceconductors,overheadsystem the service conductors.betweentheterminalsof the serviceequipmentanda pointusuallyoutsidethebuilding,clearof buildingwalls,wherejoined by tapor spliceto theservicedrop.service-tntranceconductors,undergroundsystem the undergroundservice conductorsbetweentheterminalsof theserviceequipmentandthe lastpointof connectionto theserviceentranceconductors.Note: Whereserviceequipmentis locatedoutsidethebuildingwalls,theremaybenoservice-entranceconductors,or they may be entirelyoutsidethebuilding.consumer'sin$tallationswiringandapparatussituatedupontheconsumer'spremisesinstalledandcontrolledby him,excludinganyswitchgearof theSupplyAuthoritywhichtheconsumermaybe permittedto use.5.4 GENERALREQUIREMENTS5.4.1 NumberofServicesPermitted5.4.1.1 Singleservice(1) Exceptasprovidedin 5.4.1.2'eachconsumer'sinstallationshallbesuppliedwith a singleservice.5.4.1.2 MultipleservicesUnlessprohibitedby Codeor Standardor by regulationsof theSupplyAuthorityconcerningthenumberof services,additionalservicesshallbepermittedin thefollowing cases:(a) In multiple-occupancybuilding,by specialpermission,wherethereis noavailablespace. for serviceequipmentaccessibleto all theoccupants.(b) Dueto capacityrequirements,two or moreservicesshallbepermittedwhere:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 142SECTION 5: SERVICE AND SERVICE EQUIPMENTi) the loadrequirementsarein excessof 3000.0Aata voltagesupplyof 600.0Vorless; _---/~ii) theloadrequirementsof a single-phaseinstallationaregreaterthanthatnormallysuppliedthroughoneservice.(c) For fire pumpswher~a separateserviceis required.(d) For emergency,legallyrequiredstandby,optionalstandby,or parallelpowerproductionsystemswherea separateserviceis required.(e) For differentcharacteristics,suchasfor differentvoltage,frequenciesor phase,or fordifferentuses,suchasdifferentrateschedules.5.4.1.3Marking(I) Wheremorethanoneserviceispermittedorprovided,apennanentplaqueor directoryshallbeinstalledadjacenteachserviceequipmentlocationdenotingall otherserviceson or in theconsumers'installationandtheareaservedby each.5.4.1.4 Grouping(1)Whentwo or moresupplyservicesareinstalledto a building,all serviceboxesassociatedwiththevariousconsumer'sservicesshallbegrouped,wherepracticable.5.4.2 Consumer'sInstallationNotto beSuppliedThroughAnotherBuilding(1)Serviceconductorssupplyingaconsumer'sinstallationshallnotpassthroughtheinteriorofanotherbuildingor otherstructure.5.4.3 ConductorsConsideredOutsideof a Building(1)Conductorsshall be consideredoutsideof buildingor otherstructureunderany of thefollowingconditions:(a) Whereinstalledundernot lessthan50.0mmof concretebeneatha building or otherstructure;and(b) Whereinstalledwithin a buildingor otherstructurein a racewaythat is enclosedbyconcreteor bricknot lessthan50.0mmthick./(. 143 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS5.4.4 OtherConductorsin Racewayor Cable(1) Conductorsotherthanserviceconductorsshallnotbe installedin thesameservice'wayorservice~entrancecable.Exemption: Earthingconductorsand loadmanagementcontrolconductorhavingovercurrentprotection.5.4.5 ClearancefromBuildingOpenings(1) Serviceconductorsinstalledasopenconductorsormulticonductorcablewithoutanoverallouterjacketshallhaveaclearanceof notlessthan925.0mmfromwindows,doors,porches,fireescape,or similarlocations.(2) Serviceconductorsshallnotbeinstalledbeneathopeningsthroughwhichmaterialsmaybemoved,suchasopeningsin farmandcommercialbuildings.(3) Overheadwire shallnotberunsuchthattheyobstructentranceto thesebuildingopenings.Exemption: Conductorsrunningabovethetoplevelof a windowshallbepermittedfor a clearanceof requirementsof lessthan925.0mmas in (1) above.5.5 SERVICE EQUIPMENT5.5.1 General5.5.1.1 Enclosedorguardedliveparts(1) Serviceequipment'slive partsshallbeenclosedor guardedasspecifiedbelow:(a) They shallbeenclosedso thattheywill notbeexposedto accidentalcontact;or(b) If notenclosedtheyshallbe installedon a switchboard,panelboard,or controlboardandguardedby providinga meansfor lockingor sealingdoorsgivingaccessto them.5.5.1.2 Earthingandbonding(1) Serviceequipment,raceway,cablearmour,cablesheaths,panelboards,etcandanyserviceconductorsthat are to be earthedshall be done in accordancewith the relevantParts ofSection7.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 144SECTION 5: SERVICE AND SERVICE EQUIPMENT5.5.1.3 Availableshort-circuitcurrent(1)Serviceequipmentshall be suitablefor the short-circuitcurrentavailableat its supplytenninal.5.5.1.4 Workingspace(1)Sufficientworkingspaceshallbeprovidedtothevicinityof theserviceequipmenttopermitsafeoperation,inspection,andrepairs.5.5.1.5 Location(1)Serviceboxesor otherconsumer'sserViceequipmentshall be installedin an acceptablelocationand in compliancewith applicableCodesor Standardsor by-laws of the SupplyAuthorityconcerningthe locationof serviceboxesor otherequipmentandshallbe:(a) readilyaccessibleor havethemeansof operationreadilyaccessible;(b) not locatedin coal bine, clothesclosets,bathrooms,stairways,rooms in which thetemperaturenormallyexceeds30C,dangerousorhazardouslocations,in locationswheretheheadroomclearanceis lessthan2.0m,nor in anysimilarundesirablelocations;and(c) placedwithin the buildingbeingserved,unlessenvironmentalconditionswithin thestructureare unsuitable,in which casethe-servicebox or otherconsumer'sserviceequipmentmaybeplacedontheoutsideof thebuildingor on a poleandshallbe:i) protectedfromtheweather,or beweatherproof;ii) protectedfrom mechanicalinjury if lessthan2.0maboveground;iii) placedas closeaspracticalto thepointwheretheconsumer'sserviceconductorsenterthebuilding.5.5.2 Control5.5.2.1 General(1)Everyconsumer'sinstallationshallbeadequatelycontrolledby switchgearreadilyaccessibletotheconsumerandwhichshallincorporate:(a) meansof disconnect,(b) meansof overcurrentprotection,145 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(c) meansof earth-leakageprotection(if necessary),Note: WheretheSupplyAuthorityprovidesswitchgearandpennitspartof it tobeusedbytheconsumer,theconsumerneednotthenduplicatethatpart.5.5.2.2 Meansof disconnect(1) The meansof disconnectrequiredby 5.5.2.1shallcomprisea linkedswitchsuitableforoperationon loador a linkedcircuitbreaker,arrangedto disconnectall circuit.(2) Alternatively,for systemswhereoneconductoris connectedwith earth,the linkedswitchor circuit-breakermaybearrangedto disconnectthelive conductorsonlyandan isolatinglinkmaybe insertedin theearthedconductor;suchan isolatinglink shallbeso arrangedthatit isin contactbeforethelinkedswitchcanbeclosed,or shallbesecurelyfixed.by boltsor screws./ 5.5.2.3/Overcurrentprotection(1) The meansof overcurrentprotectionreferredto in 5.5.2.1shall compriseeithera fuseinsertedin eachliveconductorof thesupplyor a circuit-breakerhavinganovercurrentreleasefittedin eachlive conductorof thesupply.Exemption: Themeansof overcurrentprotectionmaybeomittedprovidedthati) theratingofallcablesconnectedbetweentheSupplyAuthority'sfuseorcircuit-breakerandtheconsumer'ssub-circuitfuseor circuitbreakersis notlessthantheratingof theSupplyAuthority'sfuseor circuit-breaker;andii) theovercurrentdeviceprotectingall circuitscontrolledby theswitchgeararelocatedwithinthesameenclosureastheswitchgearor,alternatively,arefixedimmediatelyadjacentto it.oJ 5.5.2.4 Earth-leakageprotec#on(1) Meansfor earth-leakageprotectionshallbeprovid~dfor serviceequipmentin accordancewith Clause9.4.2,Section9.Note: Whenaninstallationisbeingplanned,it isdesirabletoconsulttheSupplyAuthority,oracompetentpersonhavingknowledgeof localconditions,to ascertainwhethersatisfactoryprotectionagainstearthleakagewill beobtainedbytheuseofthefusesorcircuitbreakersprovidedforovercurrentprotectionorbytheuseofearth-leakagecircuitbreaker.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 1465.5.2.5 Sequenceof controlSECTION 5: SERVICE AND SERVICE EQUIPMENT(1) Thesequenceof theequipmentformingtheswitchgearrequiredby 5.5.2.1shallbesuchthatthemeansof disconnectfollowstheconsumer'sterminalwithouttheinterventionof anyotherapparatus(seeFigure5.1).~ f~ lObiIIII~:~:~~n~lu~in.~p~ue.::e~t'l~~!:'~I= ::d t~c.ica~~-::~owltchaut.Included.)F.' ServicerUle.nd ncutrallink.If .ny.Wh W.tt-hourmeterand/ortime.witchwhererequlrcclforofl'-pcaklatifl'.upply.S Consumer'.linked.wltch.F.2 Consumer'.mainfu~CB Consumer'.Iinlcedextas-currcntcircuit-bRokerwithor withoutearth-Db ~~~~P,'distributionboard;Figure5.1 SeqJlenceof controlNote: Theconsumer:slinkedswitchandtheconsumer'smainfusemaybecombinedin a switchandfuseunit5.5.2.6 Detachedbuilding..,r (1) Wherea consumer'sinstallationcomprisesinstallationin two or morebuildings,separate. meansof disconnectcomplyingwith therequirementsof 5.5.2.2shall be providedin eachbuilding.5.5.2.7 Capacityofprotectivegear(1) Everymeansof overcurrentprotectionshallbesuitableforthemaximumshort-circuitcurrentattainableor available.V5.5.2.8 Discrimination(1) The characteristicsand settingsof overcurrentprotectivegear,includingfuses,and thearrangementof the installajionshall be such that discriminationin the operationof theovercurrentprotectivegearis ensured.147 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS5.6 WIRING METHODS5.6.1 UndergroundConsumer'sServiceConductors5.6.1.1 Installationandtype(1) A consumer'sserviceconductorsrunningundergroundto a buildingfromanundergroundsupplysystemor froma poleline shallbe:(a) installedin rigid conduitandbeof a typesuitablefor usein wet locations;(b) asingleor multipleconductorcablefor serviceentranceusebelowgroundprovidedthat:i) The installationis in accordancewith Section8;ii) Rigid conduitis usedfor mechanicalprotectionwhereportionsare exposedtoinjury;andHi) Thecable~withoutspliceorjoint fromapointof connectionatthesupplyserviceto theconsumer'sserviceequipmentin thebuilding.5.6.1.2 Conduittodrain(1) Consumer'sserviceconduitenteringa buildingundergroundshallbesuitablydrained.5.6.1.3 Conduitseal.(1) Consumer'sserviceconduitconnectedto an undergroundsystemshallbe sealedwith asuitablecompoundto preventtheentranceof moistureor gases.5.6.2 OverheadConsumer'sServiceConductors(1) Conductorsof aconsumer'sservicewhichis connectedto anoverheadsupplyserviceatanypointabovegroundon a buildingor otherstructureshallbe installedin a rigid metalconduitor in oneof thefollowingways,if acceptable:(a}Othertype'of rigid conduit,(b) Busway(c) Flexiblemetalconduit,theconductorsbeinglead-sheathedcable(d) Mineral-insulatedcableotherthanthelightweighttype(e) AluminiumsheathedcableETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 148SECTION 5: SERVICE AND SERVICE EQUIPMENT(f) Any othersuitabletypecable(g) Serviceentrancecable,providedthat:i) it is protectedby anacceptablemeansif within2.0mof theground;ii) thevoltagedoesnotexceed230.0Vto earth;iii) it is supportedat intervalsnotmorethan1.0m;andiv) it is mountedon insulatingsupportswhichhold it not lessthan500.Ommfrom aconductingsurface,if adjacentto sucha surface.(2) Bareoverheadsupplyconductorsrunningon theoutsidewallsof abuildingmayberunasexposedwiringusingtypesof conductorsuitablefdr exposureto theweather..(3)Thelengthof consumer'sserviceconductorsbeyondtheserviceheadshall~eadequate.toenableconnectiontotHesupplyserviceconductorsortotheconductorsreferredto in5.6.2.withaminimumlengthof 750.0mm.(4)Consumer'sservicecondqctorsshallbeprovidedwith drip loops.(5)Consumer'sservice conductorsshall be suitablefor the temperaturewhich can beexperiencedin theparticularlocality.5.7 METERING EQUIPMENT5.7.1 Connection(1)Meteringequipmentshallbeconnectedontheloadsideof theserviceboxexceptthatit maybeconnectedonthesupplywhere:(a) no live partsor wiring areexposed;(b) thevoltagedoesnotexceed380.0Vbetweenconductors;and(c) theratingof theconsumer'sserVicedoesnotexceed:i) 200.0Afor a metermountingdevice,or'ii) 600.0Afor transformerratedmetermountingdevicelocatedoutdoors.Note:- Transfonnerratedmetermountingdevicemeansametermountingdevicewithcurrenttransfonnersandwithor without testsw.itchesmountedin thesameenclosure~149 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 6CIRCUIT LOADING AND DEMAND FACTOR6.1 SCOPE(1) This sectioncoversconductorampacitiesandequipmentratingsrequiredfor consumer'sservices,feedersandbranchcircuits.6.2 NORMATIVEREFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) C22.1:1990 CanadianElectricalCode,SafetyStandardfor ElectricalInstallationsSixteenthEdition.(b) NEC Handbook 1981 National Electrical Code HandbookBased on the 1981(NEC), SeventeenthEdition.(1) For thepurposeof thisSection,thefollowingdefinitionsshallapplyin additionto thetermsdefinedin Section1.6.3 DEFINITIONSdemandfactordiversityfactorcontinuousloadit is theratioof themaximumdemandof a systemor partorasystem,to thetotalconnectedloadonthesystem,to themaximumdemand of the whole system,orpart of a system, underconsideration.theratioof thesumof the individualmaximumdemandsof thevarious subdivisionsof a system,or part of a system,to t~emaximumdemandof thewholesystem,or partof a system,underconsideration.anyconditioninwhichthemaximumloadcurrentin acircuitflowswithoutinterruptionfor a periodof not lessthan3.0hrs.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 150SECTION 6: CIRCUIT LOADING AND DEMAND FACTOR6.4 GENERAL6.4.1 CurrentCalculation(1)Whencalculatingthecurrentsfromloadsexpressedinwattsor volt-amperes,to besuppliedbya low voltagea.c. system,thevoltagedivisorto be usedshall be 230.0Y or 380.0Y asapplicable.6.4.2 YoltageDrop(1)Voltagedropin aninstallationshallbebaseduponthecalculateddemandloadof thebranchcircuitsandshallsatisfytherequirementsof Clause4.5.4.6.4.3 MaximumCircuitLoadingForloadsotherthanmotors,thetotalloadonconsumer'sservice,feederor abranchcircuitshallbe80%.of thecircuitratingwhentheloadis a continuousone..6.4.4 Useof DemandFactor(1)Wheretwo or moreloadsaresoinstalledthatonlyonecanbeusedatanyonetime,theoneprovidingthegreatestdemandshallbeusedin determiningthecalculateddemand.(2)Whereafeedersuppliesloadsof acyclicor similarnaturesuchthatthemaximumconnectedloadwill notbesuppliedatthesametime,theampacityof thefeederconductorsshallbebasedonthemaximumloadthatmaybeconnectedatanyonetime......(3) Theampacityof conductorsof a feederor branchcircuitshallnotexceedtheampacityoftheconductorsof 'theserviceor of thefeederfromwhichtheyaresupplied.6.5 SERVICES AND FEEDERS6.5.1 Single-FamilyDwellings(1)Theminimumampacityof serviceor feederconductorssupplyinga single-familydwellingshallbebasedon thefollowing:v151 EBCS-10 1995 ETHIOPIAN PiUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(a) a basicloadof 2500.0Wfor thefirst 70.0m2of living area;plus(b) anadditional1000.OWfor each70.0m2or portionthereofin excessof 70.0m2;plus(c) 3500.0Wfor anyelectric'InjeraMitad';plus(d) 6000.0Wfor asinglecookingstovehavinga ratingof 12.0kWor less,plus40% of theamountby whichtheratingof thecookingstoveexceeds12.0kW;plus(e) anyelectricwaterheaterwitha demandfactorof 100%.6.5.2 ApartmentandSimilarMulti-FamilyBuildings(1) Theminimumampacityof serviceor feed,erconductorsfromamainservicesupplyingloadsin dwellingunitsshallbebasedon thefollowing:(a) a basicloadof 2500.0Wfor thefirst 45.0m2of livingarea;plus(b) anadditional1500.0Wfor thesecond45.0m2or portionthereof;plus(c) an additional1000.0Wfor each'additional90.0m2or portionthereofin excessof theinitial 90.0m2;plus(d) 3500.0Wfor anyelectric'InjeraMitad';plus(e) 6000.0Wfor a singlecookingstovehavinga ratingof 12.0kWor less,plus40%of theamountby whichtheratingof thecookingstoreexceeds12.0kW;plus(t) anyelectricwaterheaterswith a demandof 100%(2) Theminimumampacityof serviceor feedercond~torsfromamainservicesupplyingtwoor moredwellingunitsshallbebasedonthecalculatedloadobtainedfromClause6.5.2(1)andthefollowing:(a) Exciudinganyair-conditioningloads,theloadshallbeconsideredto l;?e:i) 100%of thecalculatedloadin theunithavingtheheaviestload;plusii) 65%of thesumof thecalculatedloadsin thenext2 unitshavingthesameor nextsmallerloadto thosespecifiedin (i) above;plusiii) 40%of thesumof thecalculatedloadsin thenext2 unitshavingthesameor nextsmallerloadsto thosespecifiedin (i) above;plusiv) 25%of thesumof thecalculatedloadsin thenext15unitshavingthesameor nextsmallerloadsto thosespecifiedin (i) above;plusv) 10%of thesumof thecalculatedloadsin theremainingunits;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 152SECTION 6: CIRG.UITLOADING AND DEMAND FACTOR(b) If air-conditioningis used,theamountbywhichthesumof all theair-conditioningloadsexceeds1500.0VA shallbeadded,withademandfactorof 100%,totheloaddeterminedin accordancewith (a) above.(c) In addition,anylighting,heating,andpowerloadsnotlocatedin dwellingunitsshallbeaddedwith a demandfactorof 75%.Note: The living areadesignatedin Clause6.5.1and6.5.2shallbedeterminedfromtheoutsidedimensionsof thegroupfloor of thedwellingplus 75%of thebasementareabasedon theinsidedimensions,plusanyareawhich mightnormally be usedfor living purposeson theupperfloors.6.5.3 Schools(l) Theminimumampacityof serviceor feederconductorsshallbebasedonthefollowing:a) a basicloadof 50.0W/m2of classroomarea;plusb) 10.0W/m2of theremainingareaof thebuildingbasedon theoutsidedimensions;plusc) air conditioning,andpowerloadsbasedontheratingof theinstalledequipment.(2)Demandfactorsmaybeappliedasfollows:(a) 75% for a building with an areaupto and including900.0m2basedon the outsidedimensions.(b) For abuildingwithanareaexceeding900.0m2basedontheoutsidedimensions,theloadmay,bedividedbythenumberof squaremeterstoobtaina load-pre-square-meterratingandthedemandloadmaybeconsideredto bethesumof: Vi) 75%of theloadpersquaremetermultipliedby 900;andii) 50%of theloadpersquaremetermultipliedby theareaof thebuildingin excessof900.0m26.5.4 Hospitals(1) The minimumampacityof serviceor feederconductorsshallbebasedonthefollowing:(a) a basicloadof 20.0W/m2of theareaof the',buildingbasedon theoutsidedimensions;plus(b) 100.0W/m2for high intensityareasuchasoperatingrooms;plus(c) air conditioning,andpowerloadsbasedontheratingof theinstalledequipment153 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(2) Demandfactorsmaybeappliedasfollows:(a) 80% for a building with an areaupto and including900.0m2basedon the outsidedimensions;(b) For a buildingwith an areaexceeding900.0mbasedon the outsidedimensions,thebalanceof theloadmaybedividedbythenumberof squaremetersto obtaina load-per-square-meterratingaDdthedemandloadmaybeconsideredto bethesumof:i) 80%of the loadpersquaremetermultipliedby 900;andii) 65% of theloadpersquaremetermultipliedby theareaof thebuildingin excessof900.0m26.5.5 Hotels,Motels,Dormitories,andBuildingsof SimilarOccupancy(1) The minimumampacityof serviceor feederconductorsshallbebasedon thefollowing:(a) a basicloadof 20.0W/m2of theareaof thebuildingbasedon theoutsidedimensions;plus(b) lightingloadsfor specialareassuchasballrooms;basedontheratingof theequipmentinstalled;plus(c) air conditioningandpowerloadsbasedontheratingof theequipmentinstalled.(2) Demandfactorsmaybeappliedasfollows:a) 80% for a buildingwith an areaupto and including900.0m2basedon the outsidedimensions;b) For a buildingwith an areaexceeding900.0m2basedon theoutsidedimensions,thebalanceof theloadmaybedividedbythenumberof squaremeterstoobtaina load-per-squaremeterratingandthedemandloadmaybeconsideredto bethesumof:i) 80%of the loadper squaremetermultipliedby 900;andii) 65%of theloadpersquaremetermultipliedbytheareaof thebuildingin excessof900.0m2ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 154SECTION 6: CIRCUIT LOADING AND DEMAND FACTOR6.5.6 Other Types of Occupancy(1)The minimumampacityof serviceof feederconductorsfor the typesof occupanciesspecifiedin Table6.1 shallbebasedonthefollowing:(a) a basicloadto be calculatedon thebasisof wattspersquaremeterrequiredby Table6.1 for the areaservedbasedon theoutsidedimensions,with applicationof demandfactorsasindicatedtherein;plus(b) specialloadssuchasairconditioning,powerloads,showwindowlighting,stagelighting,etc, basedon the ratingof the equipmentinstalledwith suchdemandfactorsas arepermittedby thisCode.6.5.7 Branch Circuits(1)Conductorsof a branchcircuitsupplying'InjeraMitad'and/orcookingstovein adwellingunitshallbeconsideredashavinga demandof(a) 3.5kW for 'InjeraMitad';(b) 8.0kWwheretheratingof thecookingstovedoesnotexceed12.QkW;or(c) 8.0kW.plus40% of theamountthattheratingof thecookingstoveexceeds12.0kW.Note: For thepurposeof Clause6.5.7(1),two or moreseparatebuilt-in cookingunitsmaybeconsideredas onecooking(2)For 'Injera Mitadn and or a cooking stove installedin commercial,industrial,andinstitutionalestablishments,thedemandshallbeconsideredasnotbeinglessthantherating.(3)Thedemandloadsgivenin (1) aboveshallnotapplyto cord-connectedhotplatesor otherappliances.6.5.8 FeederDemandFactors for Lifts(1)Feederdemandfactorsfor lifts shallbeasshowninTable 6.2.155 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSTable6.1 Demandfactorfor serviceandfeedersandwattspersquaremeterforvarioustypesof occupancyDemandfactor [%]Type of OccupancyWatts per m2ServiceconductorFeedersStore, Restaurant30100100Office5070-90qOIndustrialand Commercial25100100Church / Mosque10100100Garage10100100Storage warehouse57090Theatre307595Armouries arid Auditoriums1Q80100Banks50100100Barber shops and beauty3090100parlors-.Clubs2080100Court houses207090Loadges1580100Table6.2 Feederdemandfactorsfor liftsNumber of lifts on Demand factorsNumber of lifts onDemand factorsa single feeder(OF)a single feeder(OF)11.0060.7920.9570.7730.9080.7540.8590.7350.8210 or more0.72Note: Demandfactors(DF) arebasedon 50% duty (i.e, half-timeload,half-timeno load).ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 156SECTION 7EARTHING, BONDING, AND LIGHTNINGPROTECTIONPART I - EARTHING AND BONDING7.1 SCOPE(1) PartI of thisSectioncoverstheprote;:ctionof electricalinstallationbyearthingandbonding.(2) This part also coversprovisionsfor insulatingand guardingas suitablealternativestoearthingwherepermi~d by thisCode.7.2 NORMATIVE REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) C22.1:1992(b) NFPA 701NEC:1987(c) IEE:1970157 EBCS-10 1995Canadian Electrical Code, Part 1, Safety Standard forElectricalInstallations,SixteenthEdition.An AmericanNationalElectricalCode.The Instituteof Electrical Engineers,Regulationsfor theElectrical Equipment of Buildings, FourteenthEdition,IncorporatingAmendments.ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS7.3 SYSTEM AND CIRCUITS EARTHING7.3.1 'DirectCurrentSystems(1) A two~wiredirect-currentsystemsuppiyinginteriorwiring andoperatingatnotmorethan300.0Vor not lessthan50.0Vbetweenconductorsshallbeearthed,unlesssuchsystemis used.for supplyingindustrialequipmentin limitedareasandthecircuit is equippedwith an earthdetector.(2) Theneutralconductorof all3-wire direct-currentsystemssupplyinginteriorwiring shallbeearthed.7.3.2 AlternatingCurrentSystems(1) Exceptasotherwiseprovidedfor in thisCode,alternating-currentsystemsshallbeearthedif:a) by so doing,theirmaximumvoltage-to-earthdoesnotexceed230.0Y;orb) thesystemincorporatesa neutralconductor.(2) Wiring systemssuppliedby an unearthedsupplyshall be equippedwith a suitableearth( ,..Idetectiondeviceto indicatethepresenceof anearthfault.(3) Circuitsof lessthan50.0V shallbeearthedunderanyof thefollowing conditions:a) Wlieresuppliedby transformersthatareenergizedfrom:i) systemsof morethan230.0Y-to-earth;or. ii) unearthedsystem.b) where installedasoverheadoutsideof buildings.(4) Whereprimarywindingsof currentandvoltageinstrumenttransformersareconnectedtocircuitsof 230.0V-or-more-to-earth,thesecondarycircuitsof thetransformershallbeearthed.(5) Where the transformersare on switchboards,the secondarycircuits shall be earthedirrespectiveof thevoltageof thecircuits.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 158,.SECTION 7:' EARTHING, BONDING AND LIGHTENING PROTECTION..7.4 LOCATION OF SYSTEM EARTHING CONNECTIONS7.4.1 D.C. Systems(1) D.C. systemsto bee~hed shallhavetheearthingconnectionmadeatoneor moresupplystations;butnotat individualservicesnor elsewhereon interiorwiring.7.4.2 A.C. Systems(1) An internalwiring systemthatis suppliedby ana.c.serviceandwhichisto beearthedshallhaveateachservice,anearthingconductorconnectedtoanearthelectrodewhichcomplieswithClause7.8below.(2) The earthingconductorshallbeconnectedto theearthedserviceconductoratanyaccessiblepointfromthe loadendof servicedropor servicelateral.(3) Wherethetransformersupplyingtheservicesis locatedoutsidethebuilding,at leastoneadditionalearthingconnectionshall be madefrom theearthedserviceconductorto an.earthelectrode,eitheratthetransformeror elsewhereoutsidethebuilding.(4) An earthingconnectionshallnotbemade'toanyearthedcircuitconductorontheloadsideof theservicedisconnectingmeans.(5) For circuitsthataresuppliedfromtwosourcesin a commonenclosureor groupedtogetherinseparateenclosureandemployingatie,a singleearthingelectrodeconnectionto thetiepointof theearthedcircuitconductorsfromeachpower-supplysourceshallbepermitted.(6) Wherethe systemis earthedat any point, the earthedconductorshall be run to eachindividualserviceandnotbesmallerthantherequiredearthingconductorspecifiedinTable7.1,andwherethe earthedcircuit conductoralso servesas the neutral,the requirementsof therelevantClausesof Section4 shallbemet.7.4.3 IsolatedSystems(1) For awiring systemor circuitwhichis requiredtobeearthed,andwhichis notconductivelyconnectedto a distributionsystem,theearthingconnectionshallbemadeatthetransformer,orothersourceof supply,or on thesupplysideof the first switchcontrollingthe system,andsatisfyingboththefollowingconditions:159 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUilDINGSa) The earthingconductorshallnotbesmallerthanthatspecifiedin Table7.1.b) If two or moresystemsareemployed,a commonsystemearthingconductorshallbeinstalledunlessseparateearthingis suppliedfor eachsuchsystem,in which casetheearthingfor theindividualsystemsshallbe interconnected.7.4.4 SingleServiceSupplytoTwoor MoreBuildingsor Structures(1) Whereto or morebuildingsor structuresaresuppliedfroma singleservice:a) theearthedcircuitconductorateachof thebuildingsor structuresshallbeconnectedtoanearthingelectrodeandbondedto thenon-current-carryingmetalpartsof theelectricalequipment;orb) exceptfor buildingshousinglivestock,the non-current-carryingmetalpartsof the~lectricalequipmentin or on thebuildingor structureshallbepennittedto bebondedto earthby a bondingconductorrunwiththefeederor branchcircuitconductors.7.4.5 Conductorsto beEarthed.(1) For a.c.wiring systems,theconductorsto beearthedshallbeasfollows:a) Single-phase,2-wire,theidentifiedconductor;b) Single-phase,3-wire,the identifiedneutralconductor;c) Multi-phasesystemshavingone wire commonto all phases,the identifiedneutralconductor;'d) Multi-phasesystemshavingoneearthedphase,theidentifiedconductor;e) Multi-phasesystemsinwhichonephaseisusedasin (b) above,theidentifiedconductor.7.4.6 CurrentOverEarthingConductor(1) Wherewiring systems,circuits,electricalequipment,cableannour,conduitandothermetal./ . racewaysareearthedasa protectivemeasure,theearthingshallbearrangedsothatthereis noobjectionablepassageof currentovertheearthingconductoror earthingpath.(2) If theuseof multipleearthingconnecti9nsresultsin anobjectionableflow of current,oneor moreof thefollowingalterationsshallbemade:a) Abandononeor moreof theearthes.b) Changethe locationsof theearthingconnections.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 160SECTION 7: EARTHING, BONDING AND LIGHTENING PROTeCTIONc) Interruptthecontinuityof theconductorsbetweentheearthingconnections.d) Takeothersuitableremedial'actionto limit thecurrent.Note; The temporarycurrentswhicharesetup underaccidentalconditionswhiletheearthconductorsareperformingtheirintendedprotectivefunctionsarenotconsideredobjectionable.7.5 BONDING7.5.1 Non-Current-CarryingMetalParts ..(1)Atl non-current-carryingmetalwork of wiringsystemsincludingcablesheathsandarmour,conduit,ducts,truckingboxes,andcatenarywires,shallbebondedto earth.(2)Whereisolationof metalis adoptedasaprotectivemeasure(preventionof dangerousearth-leakagecurrent),it shallbeconfinedto thefollowingitems: .a) Short isolatedlengthsof metalused'for themechanicalprotectionof cableshavinganon-metallicsheath.b) Metal clipsusedfor fixing cables.c) Smallmetalpartssuchasscrews,''rname-platesisolatedby isolatingmaterial.7.S.~ExposedNon-Current-CarryingMetalPartsof Equipment(1)Exposednon-current-carryingmetalpartsof equipmentshallbebondedto earth;howeverthisdoesnotapplyto double-insulatedequipmentor isolatedmetalpartsreferredto in Clause7.5.1(2).7.S.3 Non-MetallicWiring Systems(1) Wherenonmetallicwiring sY$temsareused:a) anearthconnectionshallbeprovidedatall outlets;andb) metalboxesshallbeearthed.'.S.4 Non-ElectricalServices(1) Metalpartsof watersupplyservicesandgasserviceswhichmaybecomeenergizedshallbebondedto earth.161 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(2) The bondingconductorshallbeattachedto thewatersupplyserviceor gasservice:a) ata locationasnearto consumer'selectricalserviceentranceasis practicable;andb) atalocationwherea sub-feederentersa building.(3) The watersupplyserviceor thegasserviceshallbebondedby meansof a copperbondingconductorriotlessthantheappropriatevalueshownin Table7.1subjectto a minimumsizeof2.5mm2Note:- i) ForthepurposeofClause7.,5theassociatedcircuitconductoristhelargestconductorconnectedintotheinputsideof theconsumer'sswitchgear.'ii) Conductorof materialotherthancoppershallhavearesistancenotexceedingthatof theprescribedcopperconductor. _Hi)Connectiontothepipesof theservicesshallbemadebymeansof aclamp.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 162SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONTable7.1 Minimumsizesof copper-earthingandcopper-bondingconductorsnotcontainedin a compositecable,flexiblecable,or flexiblecordNominalcross-sectionalNominalcross-sectionalNominalcross-sectionalare. of largestassociated are. of earthingconductorareaof bondingcoductorcoppercircuit conductormm2mm2mm21.061.0t1.561.0t2.561.0t461.0t661.0t1062.5t1662.5251663516650166-70 501695501612050161505016~185 7050.2407050300705040070505007050'6007050t 2.Smm2 for bondingmetalworkof otherservicesatpointsof entryto premises.j163 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS7.5.5 ExtraneousFixedMetalwork(1) The exposedmetalpartsof all equipmentwhichis requiredby thispartof theCodeto beearthed,whichmightotherwisecomeintofortuitouscontactwith extraneousfixed metalwork,shallbeeithereffectivelysegregatedtherefrom,or effectuallybondedthereto,soasto preventappreciablevoltagedifferencesatsuchpossiblepoints of contact.(2) For sizesof bondingconductors,refer to Table7.1.Note: Theextraneousfixedmetalworkrequiredtobebondedandearthedinthesecircumstancesincludesthefollowing:i) Bathsandexposedmetalpipes,sinksandtanks,intheabsenceofmetal-to-metaljointsofnegligibleelectricalresistances.ii) Wherepracticable,accessiblestructuralsteelwork.Hi)Frameworkof mobileequipment,suchascranesandlifts, onwhichanelectricalapparatusismounted.7.6 METHOD OF EARTHING7.6.1 EffectiveEarthing(1) Thepathto earthfromcircuits,equipment,or conductorenclosuresshallbepermanentandcontinuousandshallhave:/ a) sufficient ampacityto conductsafelyanycurrentliableto be imposedon it; andb) impedancesufficientlylowto limitthevoltageaboveearth,andtofacilitatetheoperationof overcurrentdevicesin thecircuit.7.6.2 CommonEarthingConductor(1) Theearthingconductorfor circuitsshallbepermittedto beusedasabondingconductorforequipment,conduit,andothermetalraceways,or enclosurefor conductors,includingserviceconduitor cablesheathandserviceequipment.7.6.3 CommonEarthingElectrode(1) Wherethealternating-currentsystemis connectedto anearthingelectrodein or atbuildingasspecifiedin Clauses7.4.2,thesameelectrodemaybeusedto earthconductorenclosuresandequipmentin or onthatbuilding.ETHIOPIAN BUILDING CODE STANDARDt _EBCS-10 1995 164SECTION 7: EARTHING, BONDING AND LIGHTENING PR01ECTION7.6.4 Underground Service(I) Whereanundergroundservicecableis servedfromacontinuousundergroundmetalsheathedcablesystemandthe sheathor armourof theservicecableis connectedto theundergroundsystem,thesheathor armourof theservicecableshallnotberequiredto bebondedto earthatthebuildingif it is insulatedfromtheinteriorconduitor piping.(2)Whereametal-sheathedservicecableservedfromacontinuousundergroundmetalsheathedcablesystemis bondedto theundergroundsystemandis containedin anundergroundserviceconduit,theconduitshallnotberequiredto bebondedto earthatthebuildingif it is insulatedfromtheinteriorconduitor piping.7.6.5 Short Sectionof Raceway(1)Isolatedsectionof metalracewayor cablearmour,if requiredto bebondedto earth,shallpreferablybebondedsoby connectingto otherearthedracewayor armour.7.6.6 Fixed Equipment(I) Fixedequipmentshallbebondedto earthin oneof thefollowingways:a) An effectivemetallicconnectionto earthedmetalraceways,metalsheath,or cable4 'aiIDOUrexcept:i) Armour as specifiedin Clausesin '(2) and(3) below;and/orii) sheathof mineral-insulatedcablewhenof stainlesssteelasspecifiedin (4) below;and/oriii) wheretheracewayor cablesarerununderground,in locationssubjectto corrosion.b) A bon,dingconductorwhichis runwithcircuitconductorsasapartof a cableassemblyandwhichmaybeuninsulated;but,if providedwithanindividualcovering,thecoveringshallbe finishedto showa greencolouror a green/yellowcombination.c) A separatebondingconductorinstalledthesameasabondingconductorfor conduitandthelike.d) Otheracceptablemeans.165 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(2) The armourof armouredcablesincorporatinga bondingconductorshalinotbeconsideredas fulfilling therequirementsof a bondingconductorfor thepurposeof this~lause,andthebondingconductorprovidedin thesecablesshallcomplywith (1b) above.(3) The armourof flexiblemetalconduitand liquid-tightflexiblemetalconduitshallnotbeconsideredasfulfilling therequirementsof bondingconductorfor thepurposesof thisClause,anda separatebondingconductorshallberunwithintheconduit.(4) The sheathof mineral-insulatedcablehavinga stainlesssteelshall not be consideredasfulfilling therequirementsof abondingconductorfor thepurposesof thisClauseandbondingshallbeby oneof themethodsspecifiedin (1b) or (1d) above.7.7 BONDING METHODS7.7.1 CleanSurface(I) Whereanon-conductiveprotectivecoatingsuchaspaintor enamelii usedontheequipment,conduit,couplingsor fittings,suchcoatingshallbe removedfrom threadsandothercontactsurfacesin orderto ensurea goodelectriq~1connection.7.7.2 Bondingat ServiceEquipment(1) Theelectricalcontinuityof theearthingcircuitattheserviceequipmentshallbeassuredbyoneof-themeansgivenin Clause7.7.3for thefollowingequipmentandenclosuresif of metal:a) Serviceracewaysor servicearmouror sheaths.b) All serviceequipmentenclosurescontainingserviceentranceconductorsincludingmeterfittings,boxesor the like, interposedin theserviceracewayor armour.c) Any conduitor armourwhich forms partof the earthingconductorto the serviceraceway.7.7.3 Meansof AssuringContinuityat ServiceEquipment(1) Electricalcontinuityatserviceequipmentshallbeassuredby:a) the useof threadedcouplingsandthreadedbosseson enclosureswith joints madeuptightrigid metalconduitis used;or7.7.(1)conear7.7(1)as~7.(1b:ni(ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 166SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONb) theuseof threadlesscouplingsmadeup tightwhereelectricalmetallictubingis used;orc) theuseof bondingjumpersmeetingtherequirementsof Clauses7.7.7and7.9,ord) otherdevices(notstandardlocknutsandbushings)suchasearthingbushingsequippedwith bondingjumpersmeetingtherequirementsof Clause7.7.7below.7.7.4MetalArmouror Tapeof ServiceCable(1)Whereservicecablehasanuninsulatedearthedserviceconductorin continuouselectricalcontactwith itsmetalarmouror tape,themetalcoveringshallbec,?nsideredto beadequatelyearthed.7.7.5Bondingat Other-Than-ServiceEquipment(1)Theelectricalcontinuityof metalraceway,metalsheathed,or armouredcableshall beassuredby oneof themethodsspecifiedin Clauses7.7.3or by theuseof:a) threadlessfittings,madeup tightwith conduitor armouredcable;bY two locknuts,oneinsideandoneoutsideof boxesandcabinets;orc) onelocknutanda metalconduitbushingprovidedthebushingcableinstalledso thatitis mechanicallysecureandmakespositivecontactwiththeinsidesurfaceof thebox orcabinet.7.7.6LooselyJointedMetalRaceways(1)Expansionjoints andtelescopingsectionsof racewaysshallbemadeelectricallycontinuousby bondingjumpersor otheracceptablemeans.(2)Metalthroughracewaysusedinconnectionwithsoundrecordingandreproductingequipmentmadeup in sectionsshallcontainanearthingconductortowhicheachsectionshallbebonded.7.7.7BondingJumperst(l) Bondingjumpersshallsatisfythefollowing:A bondingjumperis a reliableconductorto assuretherequiredelectricalconductivitybetweenmetalpartsrequiredto be electricallyconnected.167 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSa) They shallbe copperor othercorrosion-resistantmaterial.b) They shallbeof sufficientsizeto haveanampacitynot lessthanthatrequiredfor thecorrespondingearthingconductor.c) They shall be attachedto cabinetsand similarequipmentin a mannerspecifiedinClause7.10.4.d) They shallbe strapswhenusedfor bondingnon-current-carryingmetalparts;shallnotbe lessthan19.0mmin widthandnot lessthan.:i) l.4mm in thicknessif of steel;orii) 1.2mmin thicknessif of aluminiumor copper.7.8 EARTHINGELECTRODES7.8.1 General(1) The type and embeddeddepthof an earthelectrodeshall be suchthatthe drying andfreezingof soil will not increaseits resistanceabovetherequiredvalue.(2) The designusedin andtheconstructionof anearthelectrodeshallbesuchasto withstanddamageandto takeaccountof possibleincreasein resistancedueto corrosion.7.8.2 ServicePipeElectrode7;8.2.1 Publicwaterpipe _(1) Wherea servicewaterpipe from a public watermainto a building is usedas earthingelectrode,it shallbe:a) continuouslyconductive;b) locatedor placedundergroundnot lessthan2S0.0mmbelow the normalpermanentmoisturelevel;andc) the undergroundportion extendsnot lessthan 3.0m beyondthe extremitiesof thebuildingserved.7.8.2.2Independentmetalwaterpipes(1) Wherea conductiveindependentmetalwaterpipingsystemis usedasearthingelectrode,itshallbeplacedundergroundnotlessthan2S0.0mmbelowthenormalpermanentmoisturelevelandtheundergroundportionextendnot less3.0mbeyondextremitiesof thebuildingserved.,.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 168SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.8.2.3 Metalcasingof apump(1)Whereametalcasingof apumpsystemis usedasearthingelectrode,it shallnotbelessthan75.0mmin diameterandshallextendat least15.0mbelowthewell-head.7.8.2.4 Bonding(1) Wheremorethanoneof theearthingmeanslistedunderClause7.8.2existat a building,theyshallbebondedtogetherwith a conductorcomplyingwith Clause7.5.4(3).7.8.3 ArtificialEarthingElectrodes7.8.3.1 Concrete-EncasedElectrode(1)A concrete-encasedelectrodeshall be encasedwithin the bottom50.0mmof a concretefoundationfootingthatis in directcontactwiththegroundandshallbe:a) a barecopperconductornot lessthan6.0min lengthandof sizespecifiedin Table7.2,orb) a plateelectrodethatshall:i) presentnot less0.4m2of surfaceto theconcreteencasingtheplate;ii). be not lessthan6.0mmin thicknessif of iron or steel;or i .5mmin thicknessifnon-ferrousmetal;andiii) have a meansof attachmentfor' the systemearthingconductorthat shall beaccessibleaftertheconcreteis poured.Table7.2 Minimumsizefor concreteencasedelectrodesAmpacity of largest associatedSize of copper conductorcircuit conductor [(mm2][A]160 or less25161-25035251 - 33550356 - 50070above 50095169 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS, 7.8.3.2 Rodelectrode(1) A rod electrodeshall:a) benot lessthan16.0mmin diameterif of ironor steel,or 12.7mmif non-ferrousmetalor ferrousmetalcladwith a non-ferrousmetal;b) benot lessthan3.0min length;c) havea cleanmetalsurfacewhich is not coveredwith paint,enamel,or otherpoorconductingmaterial;andd) bespacednot lessthan3.0mapart(if morethantworodsarerequired).7.8.3.3 Plateelectrode(1) Plateelectrodeshallpresentnot,lessthanO.2m2of surfaceto exteriorsoil andbe not lessthan6.35mmin thicknessif of ironor steel,or 1.5mmif of ferrousmetal.7.8.3.4 Laying(1) An artificialearthingelectrodeshallbeburied:.a) at least250.0mmbelowpermanentmoisturelevelasfar aspractical;b) in a horizo,lltaltrenclwhererockbottomis encounteredatdepthlessthan1.2m.7.8.3.5 Drivingrodelectrode(1) A rod electrodeshallbe drivento a depthof no lessthan3.0mregardlessof the sizeornumberused,exceptthat:'.J.a) whererockbottomis encounteredatadepthof 1.2mor more,it shallbedrivento rockbottom;orb) whererock bottomis encounteredata depthof lessthan1.2m,it shallbeburiedin ahorizontaltrenchandbenot less3.0mlong.7.8.3.6 ~l'acing(1) Each electrodeshall be separatedat least2.0m from any otherelectrodeincludinganelectrodeusedfor signalcircuits,radio,lightning,or anyotherpurpose.ETHIOPIAN BUII,..DINGCODE STANDARD EBCS-10 1995 170SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.8.3.7 Connectionof electrodes(1)Whereseparationof thedifferentsystemelectrodesis notpossible,theelectrodesshallbeconnectedtogether,ator belowgroundlevel,withacopperconductorof asizenotlessthanthatoftheearthingconductorfor theelectricalsystemandin nocaseshalltheconductorbesmallerthanl6.0mm2copper.7.8.3.8 Bonding(1)Whereany or all of the separateearthingelectrodesare bondedtogetherthe bonding,conductorshallbe:a) a copperconductornot smallerthanl6.0mm2;b) installedso asnot to besubjectedto mechanicaldamage;andc) connectedtoelectrodesfor powersystemsbymeansof aboltedclampor solderedjointsandpreferablybeconnectedto otherelectrodesin thesamemanner.7.9 EARTHING AND BONDING CONDUCTORS7.9.1 General7.9.1.1 Continuityof earthingandbondingconductors(1)No automaticcutoutor switchshallbe placedin theearthingor bondingconductorof awiringsystemunlesstheopeningof thecutoutor switchdisconnectsall sourcesof energy.7.9.1.2 Materialfor systemearthing(I) The earthingconductorof a wiring system,whetheralso usedfor earthingelectricalequipmentor not,maybe insulatedor bare,an~shallbeof copper.7.9.1.3 Materialfor bondingconductors(1)The earthingconductorof a wiring system,whetheralso usedfor earthingelectricalequipmentor not,maybe insulatedor bare,andshallbe:a) a conductorof copperor othercorrosion-resistantmaterial,insulatedor bare;b) abusbar or steelpipe; _171 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS .c) rigid metalcanduit,exceptwhereusedundergraundar in anylacatianwherematerialhavinga deteriaratingeffectmaycameinto.cantactwith themetal,ar in anyexpased.racewayinstalledautdaarswhereitmaybesubjectto.mechanicaldamageframvehiculartraffic, in which casea separatecanductaras requiredin (a) abaveshall be installedwithin thecanduit;d) electricalmetallictUbing,exceptwhereusedincancretearmasanryslabsin cantactwiththegraundar in anylacatianwherematerialhavingadeteriaratingeffectmaycameinto.cantactwith themetal,ar in anyexpasedracewayinstalledautdaarswhereit maybesubjectto.mechanicaldamageframvehiculartra~c, in whichcase,separatecanductarasrequiredin (a) abaveshallbe installedwithin'thetubing;e) thesheathaf mineral-insulatedcable,exceptwhenit is stainlesssteel,ar anycanductaraf amineral-insulatedcableif it is permanentlymarkedatthetimeaf installatianso.thatit canbereadilydistinguishedframcanductarsthatarenatusedasbandingcanductars,exceptthatif thesheathis af aluminiumin anundergraundrun ar in a lacatianwherematerialshavinga deteriaratingeffectmaycamein cantactwith themetal,carrosionresistantprotectionsuitablefor thecarrasiveconditionencaunteredshallbe provided;f) thesheathaf aluminium-sheathedcable,butif usedfar undergroundrunsor in lac~atianswherematerialshavinga deterioratingeffectmay camein contactwith the metal,c~)ITasian-resistantpratectiansuitablefar thecorrasivecanditionsencaunteredshallbepravided;arg) athermetalracewaysor cablearmaurasprovidedfor in Clause7.6.6.7.9.2 Installationof EarthingConductorsfor a System(1) The earthingcanductarfar a systemshallbewithautjaint ar splicethroughautits length,exceptin thecaseaf busbars,thermitweldedjaints, campressianconnectarsappliedwith acampressiantaalcompatiblewiththeparticularcannectar,ar devicesacceptablefar connectionin serieswith theearthingcanductor.(2) 16.0mm2ar largercapperearthingcanductarwhich is free from expasureto.mechanicalinjury may be run alangthe surfaceaf the buildingconstructianwithautmetalcaveringorprotectian,if it is rigidly stapledto.thecanstructian;o.therwise,it shallbe in conduit,electricalmetallictubingor cablearmour.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 172SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION(3) A copperearthingconductorof IO.Omm2shallbe in conduit,electricalmetallictubingorcableannour.(4) Metalenclosuresfor earthingconductorsshallbecontinuousfromthepointof attachmen~tocabinetsor equipmentto theearthingelectrodeandshallbesecurelyfastenedto theearthingclampor fitting.(S) Whereanearthingconductoris runin thesameracewaywithotherconductorsof thesystemtowhichit is connected,it shallbeinsulated,exceptthatwherethelengthof theracewaydoesnotexceedIS.Ombetweenpull pointsanddoesnotcontainmorethantheequival~ll_tof twoquarterbendsbetweenpull points,anuninsulatedearthingconductormaybeused.(6) Notwithstandingtherequirementsof (2)above,earthingconductorof I6.0mm2or largermaybeembeddedin concreteprovidedthatthepointsof emergencyareso locatedor guardedasnotto constituteexposureto mechanicalinjury.7.9.3 Installationof BondingConductorsfor Equipment(1) The bondingconductorfor equipmentshallbepennittedto be splicedor tapped;butsuchsplicesor tapsshallbe}.nadeonlywithinboxesexceptthat,in thecaseof openwiring,theyshallbepennittedto be-madeexternallyfromboxesandshallbecoveredwith insulation.(2) Wheremorethanonebondingconductorentersa box,all suchconductorsshallbe in good. electricalcontactwith eachotherby securingall bondingconductorsunderbondingscrews,orby connectingthem togetherwith an acceptablesolderlessconnectorand connectingoneconductoronly to thebox by a bondingscrewor a bondingdevice,andthearrangementshallbesuchthatthedisconnectionor removalof a receptacle,fixture,or otherdevicefedfromthebox,will not interferewith or interruptthebondingcontinuity.(3) Wherea bondingconductoris runin thesameracewaywithotherconductorsof thesystemtowhich it is connected,it shallbe insulated,exceptthatwherethelengthof theracewaydoesnot exceedI5.0m anddoesnot containmorethanthe equivalentof two quarterbends,anuninsulatedbondingconductorshallbepennittedto beused.(4) Wherea t;igidmetalconduitor steelpipe is usedasa bondingconductor,the installation.shallcomplywith Section8 of thisCode.173 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS(5) A copperbondingconductorshall:a) if 16.0mm2or largerand attachedsecurelyto the surfaceon which it is carried,beprotectedwhereexposedto mechanicalinjury;andb) if smallerthan16.0mm2or if theinstallationdoesnotcomewithintheprovisionin (a)above,beinstalledandprotectedin thesamemannerasthecircuitconductorfor agiveninstallation.(6) An aluminiumbondingconductorshall:a) if 25.0mm2or largerandattachedsecurelyto the surfaceon which it is carried,beprotectedwhereexposedto mechanicalinjury;orb) if smallerthan25.0mm2or if theinstallationpoesnotcomewithintheprovisionsin (a)above,beinstalledandprotectedin thesamemannerasthecircuitconductorfor agiveninstallation.(7) Wherea separatebondingconductorsupplementsthebondingaffordedby a ferrousmetalraceway,it shallbe installedin thesameracewayasthecircuitconductor.7.9.4 EarthingConductorSizeforD.C. Circuits(1) The ampacityof theearthingconductorfor adirect-currentsupplysystemor generatorshallbenot le~sthanthatof thelargestconductorsuppliedby thesystem,exceptwheretheearthingcircuitconductoris aneutralderivedfromabalancerwindingor a balancerset,thesizeor theearthingconductorshallbenot lessthanthatof theneutralconductor.(2) The systemearthingconductorshallbe copperandin no casesmallerthanIO.OmrW.7.9.5 EathingConductorSizefor A.C. System(I ) The sizeof theearthingconductorshallnotbe lessthanthosegivenin Table 7.17.9.6 BondingConductorSize(1) The sizeof abondingconductorshallbenotlessthat.lthatgivenin Table7.1;butin nocasedoesit needto be largerthanthelargestunearthedconductorin thecircuit.-,ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 174SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.10 EARTHING AND BONDING CONDUCTOR CONNECTIONS7.10.1BondingConductorConnectiontoRaceways(1) The pointof connectionof thebondingconductorto interiormetalraceways,cablearmourandthe like shallbeasnearaspracticableto thesourceof supplyandshallbechosenso thatno racewayor cablearmouris bondedthrougha run of smallersize that is called for inClause7.9.6.7.10.2EarthingConductorConnectiontoWaterPipeElectrodes(1) Wherethe earthelectrodeis a metalwater-pipingsystemto which a commonearthingconductoror theearthingconductorof a systemis attached,thepointof attachmentshallbea) on thestreetsideof thewatermeter;orb) on a cold-waterpipe of adequateampacityandas nearas practicableto thepoint ofentranceof thewaterservicein thebuilding.(2) Wherepracticable,thepointof attachmentshallbeaccessible.(3) The metal cold water systemshall be madeelectricallycontinuousfrom the point ofattachmentof theearthingconductorto thewaterserviceentranceby bondingtogetherall partsthereofif thesepartscontaininsulatingsectionor maybecomedisconnectedatmeters,valvesandunions.(4) Equipmentmaybeearthedto a cold-waterpipewhich is neartheequipment.7.10.3EathingConductorConnectionsto Other-Than-Water-PipeElectrodes(1) WhereaImetalwater-pipingsystemis notavailable,theearthingconductorshallbeattachedtootherelectrodesata pointwhichwill assurea permanentearth.(2) Wherepracticable,thepointof attachmentin (1) aboveshallbe accessible.175 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD---------------ELECTRICAL INSTALLATION OF BUILDINGS7.10.4 Bonding Conductor Connectionto Circuits and Equipment(1) The bondingconductoror bondingjumpershallbe attachedto circuits,conduitscabinetsequipmentandthe like, which areto be bonded,by meansof lugs,pressurewire connectorclamps,or.otheracceptablemeans.(2) Connectionswhichdependon solderingshallnotbeused.(3) The bondingconductorshallbesecuredto everymetalbox by meansof a bondingscrewwhichshallbeusedfor no otherpurpose.(4) Thebondingconductorshallbebroughtintoeverynonmetallicoutletboxin suchamannerthanit canbeconnectedto anyfittingor devicewhichmayrequirebondingto earth.(5) Equipmentshallbe so installedthat,if theconnectionsbetweenthebranchcircuitandthe. internal conductorspass throughan accessc'over,the bonding connectionshall remaincontinuouswhenthecoveris removed.(6) A bondingjumper shall be installedto connectthe bondingconductorto the earthingterminalof a socketoutletandin sucha mannerthatdisconnectionor removalof thesocketoutletwill not interferewith or interruptearthingcontinuity.(7) In the caseof metal-enclosedsystemswherethe earthingpathis providedby the metalenclosure,abondingjumpershallbeinstalledtobondtheearthingterminalof thesocketoutletto theenclosure.(8) NotwithstandingtheProvisionsof (6) and (7) above,thebondingjumper,in thecaseofsocketoutletshavingearthingterminalsisolatedfromthemountingstraprequiredfor specialequipment,maybeextendeddirectlybackto thedistributionpanel.7.10.5 Earthing Conductor Connectionto Electrodes(1) The earthingconductorshallbeattachedto theearthingelectrodeby meansof:a) a boltedclamp,b) a pipefittingplugor otherdevicescrewedintothepipeor intothefitting,c) copperweldingby thethermitprocessbrazingor silversolder,ord) otherequallysubstantialmeans.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 176SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION(2)Wherea boltedclampis usedfor a wet locationor for directearthburial,theclampshallbeof copper,bronzeor brass,andtheboltsshallbeof a similarmaterialor of stainlesssteel.(3)The earthing conductor shall be attachedto the earthing fitting as required byClause7.10.4(1).(4)Connectionswhichdependonsoldershallnotbeusedexceptfor connectionsutilizingsilversolder.(5)Not morethanoneconductorshallbeconnectedto theearthingelectrodeby a:singleclamporfittingunlesstheclampor fittingis specificallydesignedfor multipleconductorconnection.177 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 7EARTIllNG, BONDING, AND LIGHTNINGPROTECTIONPART II - LIGHTNING PROTECTION7.11 SCOPE(1) This Partof theCodecoverstheinstallationof lightningprotectionrequirementsfor all typesof structureswith theexceptionof thosestructuresusedfor manufacturingexplosives.(2) Electric generation,transmissionand distributionsystems,overheadtelephonelines,and ,radarstationsarenotcoveredby thisCode.7.12 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) BS 6651:1986 BritishStandardCodeof Practicefor Protectionof StructuresagainstLightning,1990(b) NSI/NFPA78:1986An AmericanNationalStandard),LightningProtectionCode.(c) UL 96A:1983 UnderwritersLaboratoriesStandardforInstallationRequirementsforLightingProtectionsystems,Ninth Edition.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995. 178SECTION 7: EARTHING, BONDING AND UGHTEN1NG PROTECTION7.13 DEFINITIONS(1)ForthepurposeQfthis Section,In additionto thetermsdefmedin SectionI, thefollowingdefinitionsshaliapply:lightningflashlightningstrikelightningstrokean electricaldischargebetweencloud and earth,of atmosphericorigin,comprisingoneormoreimpulseof manykiloamps.a lightningflash,attachingto a ,structure.oneof the singledistinguishable-currentimpulsesof a lightningflash.lightningprotectionsystema'completesystemof airtermination,conductors,earthtermination;interconnectionconductors,and other connectorsand fittingsrequiredtoprotecta'structurefromtheeffectof.lightning.airtermin-ationdownc;onductorb-ondjointtestjointearth'termination179 EBCS-10 1995thatcomponentof a lightningprotection'systemthatis intendedtointerceptlightnirrgflushes.a conductorintendedto beusedto'carrylightningcurren:tsbetweenair lermirration1U1d~arthtemrimrtioo.'aconductorintendedto prov.ide:eIectrica1connection'betweentheliglftrringprotectionsystem,and'Othermetal-woiksand betweenvariousporti'Onsof thelatter.a mecbanica1and/or electricaljunction betweentwo or moreport-ionsof a lightningproteCtionsystem.ajoint designedandsituatedsoastoenable.resistance'or'Continuitymeasurementto bemade.that part of a lightningprotectionsystemwhich is intendedtodischarge'lightningcurrentsintothegeneralmassof earth.ETHIOPIAN ,BUILDING CODE STANDARD-ELECTRICAL INSTALLATION OF BUILDINGSring (loop)earthelectrodeanearthelectrodefonninga closedlooproundthestructurebelowor on thesurfaceof theearth,or within or underthefoundations.It maybe~sedfor interconnectingotherearthelectrodes.sideflashzoneofprotection7.14 MATERIALS7.14.1Generalan electricalspark,causedby differencesof potential,occurringbetweenconductivemetal bodies and componentof lightningprotectionsystemor earth.thatspaceadjacentto a protectionsystemwhich is substantiallyimmuneto directlightningflashes(seeFigure 7.2).(1) A lightningprotectionsystemtshallbemadeof materialsthatareresistantto corrosionorshallbeacceptablyprotectedagainstcorrosion.(2) No combinationof materialsthatformsan electrolytic-coupleof suchnaturethat,in thepresenceof moisture,corrosionis acceleratedshallbeused.Note: Oneor moreof thefollowingmaterialsareacceptable:i) Copperofthegradeordinarilyrequiredforcommercialelectricalwork,generallydesignatedasbeingof98%conductivitywhenannealed.ii) A copperalloyasresistanttocorrosionascopperundersimilarcondition.iii) Aluminiumconductorsof electricalgradealuminium.iv) Galvanizedsteelwithcross~sectionalareaequivalenttothatof copper.7.14.2GalvanicCompatibility(1) Metals shallbeusedin combinationthataregalvanicallycompatible.t Theprincipalpartsofa lightningprotectionsystemareairtermination,downconductors,jointsandbonds,testjoints,earthtermination,andearthelectrode.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 180SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.14.3Corrosion Protection(1)Componentsshall be protectedagainstcorrosion; any part of a coppersystemthat isexposedto directactionor chimneygasesor othersimilarcOlTosivegasesshallbeprotectedbyaco,ntinuoushot-dippedcoatingof lead.(2)All componentslocatedwithin610.0rnmof thechimneytop shallbeso protected.(3)Aluminiumcomponentsarenotrequiredto havea coatingof lead.7.14.4MechanicalProtection(1)Any part of a lightning protectionsystemthat is subjectto mechanicaldamageordisplacementshallbeprotectedwith a protectivemouldingor tubing.(2)Metalpipeor tubingshallbebondedto theconduitatbothendsof thetubing.(3)Conductorsshallbesecurelyattachedto objectsuponwhichtheyareplaced(seeFigure7.1andTable7.5).7.14.5Useof Aluminium(1)Aluminiumsystemsshallbeinstalledin accordancewithotherapplicableclausesandsubjecttothefollowingconditions:a) Aluminiumlightning-protectioncomponentsshallnot be installeddirectlyon copperroofingmaterialsor othercoppersurfaceswhereexposedto therun off from coppersurfaces.b) (i) Aluminiumcomponentsshallnotbeusedwheretheycomeintodirectcontractwithearth.(ii) Fittingsusedfor theconnectionof aluminiumearthingequipmentshallbe of thebimetallictype; suchbimetallicconnectorsshallbeinstallednotlessthan460.0mmabovegroundlevel.181 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDltL.EC'f'RjCAbINSfALbAllCN OF BUILDINGS,.h. ... _ .._ . _.c) AluminiumconductotsandcomponerttsshaHhotbei)embedded in Cbncreteor masonry,;Ii) ih directcontactwith a surfacecoatedwith artalkalinebasepaint;m-iH) installedin a l'Ocatibrisubjectto excessivemoisture.Note:' Co'pperlightning-protectioncomponentsshaHnotlieinsfalleddirectlyonalumihiumrouting,sidingorotheraiuminiumsurfaces,ETH'IOPIAN 'B'UIL.O~NGCObE STANDARD ESCS-101995 1'2S50TION 7: E:ARTHINCJ,~ONDING AND l-:'GHT~NINaP-RQT~Q'fIGNCO!l'lPpnent.P!m~'e!(lfiemmArea.dCompgnentmm~Airtermination!!;~urpirium,c;opper1I11c1.gl!lvan~{l~~1l81!!trip.alu!TI!nilm,allminilmalloy,copper,I1ho~phor,b.rc:mze~dgalvanizedsteel rodsSuspllndlldconductors:~randedah,lIT1inium~rlll'1c1.e~c;opp{lrstranglldllIuminium(~llllireinforc{ld)lrllOdedgalvanized~lllliP9Wl1C;qnd4ctOI'1l:~!mil1hJm,popper!!'ldQalvanizedsteelstrip20 lC2.58.0dia.7/3.01~/1.87/3.07/~,0509~O.OSO.Q5p.050959,050.()Fixe~co'~iQl'!l (Qond!l)InllI.uminiJ!'fl,alurnlnilmalloy, Plpl?llrAAd IalVl~!ldst,~I;{lxterpaj~~pexterl'alrodllIntllmal!l'ripinterp.l!lrodsFlexi!?l@or larnln~edcpnn~i9nll(bondli);llJdernal,a14miF1iume>lemal,,,'l1ealel;coppllrinternal,aJurnil1luminternal,aon'aJe9 Cppptlr?Q x g,?llOdi~2,0 ~ 1.?e.? dis,20 x 2.520 x 2.520x 1.520 x 1.55().Q5()()3().()~~.O50,050.0~O.Qi30.Q~Y!'fliF1ilm,~l,Iminium~19Y,pOPPllr I1dJ~Y~iz{ldsteel r!XIs~~htllrrninl!tions:!!y~@niticiron9QP!!llr!l!1dgaly~izedstlllli~ripcQPper!lAdg~Iv!ll1iz~stefllrOOshardqraWncopperrqgsfor girect~rivingintosoftIroundh!lJ'd~rawnor8F1nealedcopper r9d~orsQlid wires foriF1dirllgtdrivingorlayint!in lroundrodsfor h!lJ'd:Iroungc;opp@r-c!adorIalvan~ecl.steel rQds(s~ nQte!!tQtabl@)forharcler:Ir94F1c1183 EBCS~10199~11.0c;jia. 50.q11;3.0o FQrELECTRICAL INSTALLATION OF BUILDINGSTable7.4 Minimumthicknessesof sheetmetalusedfor roofingandformingPart oftheair terminationnetworkMaterial MinimumthicknessMaterialMinimumthickness[mm][mm]Galvanized steel0.5Aluminiumnd0.7Stainless steel0.4Zinc 2.0Copper0.3LeadNote: The figuresin this tablearebasedon contemporarybuildingpracticeandwill be satisfactorywheretheroofsform partof thelightningprotectionsystem.However,damagebywayof puncturingmayoccurwithadirectarc-connectedstrike.Table7.5 Recommendedfixingcentresfor conductorsArrangement Fixing centres [mm]~Horizontal cond!Jctors on horizontalsurfaces1000Horizontal conductor~on verticalsurfaces500Vertical conductors1000Vertical conductors over 20.0m750Vertical conductors over 25.0m500Note: This tabledoesnot applyto built-in typefixings which may requirespecialconsideration.7.15 FORM AND SIZE7.15.1Air Termination(1) Verticalair tenninationsshallbemadeof solidor tubularrods.(2) Horizontalair terminationsshallbemadeof solidconductor,stripsor cables.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 184SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.15.2Conductors(1) Conductorsshallbe in theformof multiplestrandcables,singlewires,rods,or flat strips.7.15.3EarthTermination(1) Earthterminationshallbemadeof rodsplatesor ,strandedcables.7.15.4MinimumDimension(1) Thecomponentpartof lightningprotectionsystemshallhavedimensionsnotlessthanthosegivenin Tables7.3and7.4.7.16 AIR TERMINATION7.16.1General(1) Ajr terminationnetworksshallbeprovidedfor all partsof a structurethatarelikely to bedamagedby directlightningFlashes.Note: Air networksmayconsistof verticalor horizontalconductorsor combinationor both. Various formsof airterminationsare shownin Figures7.7 through7.15.7.16.2Support-(1) Verticalairterminalsshallbesecuredagainstoverturningeitherbyattachmentto theobjectto beprotectedor by meansof braceswhichshallbepermanentlyandrigidly attachedto thebuilding.7.16.3MetallicProjections(1) All metallicprojectionson or abovethemain surfaceof the roof which are connected,intentionallyor fortuitously,to thegeneralmassof theearthshallbebondedto andformpartof theair terminationnetwork(seeFigures7.4and7.5).185 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLA TlON OF BUILDINGS7.16.4MetallicMaterials(1) Metalliccoping,roofcoverings,handrails,windowwashingequipmentandmetallicscreensaroundplayareasshallbe consideredfor inclusionaspartof theair terminationnetwork(seeFigures7.4,7.5and7.6).7.16.5StructurewithinZoneof Protection(1) Air terminationshallnotberequiredfor thosepartsof a structurelocatedwithin azoneofprotection.(2) If portionsof a structurevaryconsiderablyin height,anynecessaryair terminationor airterminationnetworkfor the lowerportionsshallbejoineQto thedownconductorsof thetallerportionsin additiontJt> beingjoinedto theirown downconductor.7.16.6Air TerminationonRoof(1) Oneroof air termination'shallbeplacedor.ridgesof a roof andaroundtheperimeterof theroof.7.16.7Air TerminationonReinforcedConcreteStructure(1) If thereinforcingbarsareusedasdownconductors,theair terminationshallbeconnectedto thereinforcedbarsin thenumberof positionsrequiredfor downconductors.7.17 DOWNCONDUCTOR7.17.1General(1) A down conductorshall providea low impedancepath from air terminationto earthterminationsothatthe lightningcurrentcanbesafelyconductedto earth.Note: In additionto thevarioustypesof downconductors;i.e., strips,rods,reinforcingbarsandstructuralsteelstanchions,etcanygoodconductorwhichmayformpartof thebuildingstructurecanbeincludedprovidedthat it is appropriatelyjointed to the air andearthterminations.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 186--- ----------SECTION'?': EARTHING, BONDING AND liGHTENING PROTECTION7.17.2RoutingDownconductorsshallfollow themostdirectpathpossiblebetweenair andearthterminationnetworks.The conductorsshallbearrangedasevenlyaspracticablearoundtheoutsidewallsof.thestructure(seeFigure7.17).7.17.3RecommendedNumber(I) At leasttwo downconductorsshallbeprovidedon anykindof structure.7.17.4MechanicalProtection(1)Eachdownconductorlocatedin arunway,schoolplayground,orothersimilarlocationshallbeguardedagainstmechanicaldamageordisplacement.(2)Thedownconductorshallbeprotectedfor aminimumdistanceof 1.8mabovegradelevel.7.17.5CorrosiveSoil(1)A downconductorenteringcOITosivesoil shallbeprotectedagainstcOITosionfor not less.than91S.0mmabovegradelevelandfor entirelengthbelowgradelevel.7.17.6ExternalRoutesNotAvailable(I) Whentheprovisionof suitableroutesfor downconductorsis impossible,egobuildingsofcantileverconstructionfrom first floor upwards(seeFigure 7.18),downconductorsshallnotfollowtheoutsidecontoursof thebuildings.(2)In casessuchas (1) above,downconductorsmaybe housedin an air spaceprovidedbynon-metallic,non-combustibleinternalductandtakenstraightdownto ground.Note: Any suitablecoveredrecessnotsmallerthan76.0mmx 13.0mmoranysuitableserviceductrunningthefullheightof thebuildingmaybeusedforthispurposeprovidedit doesnotcontainanunarmoredor non-metal.sheathedservicecable.(3)In casewhereanunrestrictedductis used, sealsateachfloor levelmayberequiredfor fireprotection.(4)Where p()ssible,accessto theinteriorof theductshallbeavailable.187 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS7.17.7Lift Shafts(1) Lift shaftsshallnotbeusedfor fixing downconductor.7.17.8Re-entrantLoops(1) Whena largere-entrantloops[s~eFigure7.18(b)] cannotbeavoided,theconductorshallpassthroughholesasshownin Figure7.18(c).7.17.9SharpBends(1) No bendof a conductorshallfonn an includedangleof lessthan90 or havea radiusofbendlessthan203.0mm(seeFigure7.16).7.17.10 Bondingto PreventSideFlashing(1) Any metalin or fonningpartof thestructureor anybuildingserviceshavingmetallicpartsby designor fortuitouslyandin contactwith generalmassof theearthshallbeeitherisolatedfrom or bondedto thedownconductor.Note: Unlessextrabondingis required,itemsalreadyin metalliccontactwith the lightningprotectionsystem,directlyor indirectly,throughpermanentandreliablemetal-to-metaljoints donotrequireadditionalbondingconductors.7.17.11 Bonds7.17.11.1General(1) Since bondshaveto join a varietyof metallicpartsof differentshapesandcomposition,carefulattentionshall be givento.themetalsinvolved;i.e, thatof thebondandof the itemsbeingbonded.7.17.11.2Mechanicalandelectricalrequirements(1) A bond shallbe mechanicallyandelectricallyeffectiveandprotectedfrom corrosionanderosionby theoperatingenvironment.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 188SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION7.17.11.3Externalmetal(1) Externalmetalon or formingpartof a structureshallbebondedto thelightningprotectionsystemwith a main-sizedconductor.7.17.11.4Internalmetal(1) Internalmetalbondsmaybereducedin size;butshallnotbesmallerthan35.0mm2copperor itsequivalent.7.17.11.5Provisionfor bondingoffutureequipment(1) In all buildings,ateachfldor level,provisionshallbemad~for bondingfutijremachineryor equipmentto the lightningprotectionsystem;i.e, by connectionto metallicgas,water,drainageor similarservices.7.17.11.6Joints(1) Joints shall:a) be asfew aspossible;b) bemechanicallyandelectricallyeffective;.c) beprotectedagainstcorrosionor erosionfromtheelementsof theenvironment;andd) presentanadequatecontactarea.Note: ContactsurfaceshallfIrstbecleanedandtheninhibitedfromoxidationwitha suitablenon-corrosivecompound.(2) With overlapjoints, theo,rerlapshallnotbe lessthan20.0mmfor all typesof conductors.7.17.12 TestPoints(1) Earthdownconductorshallbeprovidedwith a testjoint in sucha positionthat,whilstnotinviting unauthorizedinterference,it is convenientfor test(seeFigure 7.25 for typicaltestjoints),Note: Platesindicatingtheposition,numberandtypeof earthelectrodesshouldbefIttedaboveeachtestpoint.189 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD'E~eCTRICALINSTALLATION QF BUILDINGS1.18 EARmTERMlNATION1.18.1Termination(1) Eachdownconductor!thallterminateatanearthelectrode.7.18.2.Re$istaneeto Earth(l) Eachearthelectrodeshallhavea resistance(in ohm)not.exc~dingtheproductgivenby 10timesti.NnumberQf eartheleotrodesto beprovided.. .(2) The whole of theearthterminationnetworkshallhavea combinedresistanceto earthntexceeding1Q ohmwithouttakingaccountof anybondingto otherservices.7.18..3 EartllEl~trodea7.18.3.1General(l)Earth eleotrodesshalloonsistof metalrods~tubesOf stripsor a combinatiol.lof theseOrnaturalearthssuchaspilesandfoundatiol.ls(seeFigure7.20).7.18.3.1 Earthrodcmmection(1) Earthrod connectionsshallbemadeby welding,bracingor clamping.(2) Clampsshallbe securedwith at leasttwo boltsor screwcapsandshallmakeContactwiththeearthrod for at least380.0mm.7.18.4Conn~tionPoint(1) The point of connectiol.lof the earthterminationnetworkshallbe removableandeasilyaccessiblefr'Om above~earthto facilitateinspectiol.l,testingandmaintenanceof the Ughtnil.lgprotectionsystem.(2)If below ground,the point of COnl.lectionshall preferablybe housedin a purpose'built... h bmspectlonpIt or c.am er.ETHIOPIAN BUILDING CODe STANDARD EBCS ..10 1995 190SECTION 1: EARTHING, BONDING ANDL1GHTEN1NG PROTECTION.', .,.,._ .._. B' __ ' 'n~'_ . __ ..~u __ .. _. __ '. __ . __ , ,_.' '_.'_'_'_'7.18.4.1Deepmoistclaysoil(1) 'Earthingrod ,shallextendverticallynot lessthan3J)m intotheeatth.(2) Thegroundshallbecompactedandm:adetightagainstthefull leltgthof thecond:uctrrrorearthrod (seeFigure7.19).1.18.4.2 Sandyor,gravelysoilto In sandor gravel,two or more'earthrodsatnot lessthan3.0m:spacings'shallbedrivenverticallyto a minimumdepthof 3.0mbelowgrade(seeFigure7.21).7.18.4.3 Shallowtopsoil(1) if bedrockis neatthesurface,theconductorshanbe laid in trenclresextendingawayfromthebuildingateachdownconductor.(1) Trenchesin (1) above::shallat leastbe:a) 3.7mlong and610,Ommdeepin day soi~b) 703m longand610.0mffideepin slll1dyOf gravely~oi1-.(3) If thesemethodsshouldproveimpracticablejthe lightningptoteetloncahlemaybe :laiddirectlyon thebedrockwith am1nimumdistanceof 610J)mm fromthefomid-ation'C)r'exteriorfootingandtermin'iltehya:ttachrn:entto a buriedcopperearthplatea'tltlastO.:8mmthic'kandhavingamlnimufil surfaceareaof 'O.18m21.18.4.4 SoillessthanO.3mdeep(I) If soil is lessthanO.3min depth,downconductorsshallbeconhectedto a 1000pconductotinstalledin a trenchor in rock:ctevlcesaroundthestrucmre.(2) '(1)The 100pconductorshall not be lessthanthe equivalentof :amainsize lightningconductor.191 EBCS-10 1:995 'ETH10PtANB'UILD1NG OODe -STANOA'AO.ELECTRICAL INSTALLATION OF BUILDINGS,{ii) Optionalearthplatesmay be attachedto the loop conductorto enhanceits earthcontact,wherethe measuredearthingresistanceis found to be high to provideeffectiveearthing(seeFigure7.22).7.18.4.5 Earthelectrodesealfor usewithina tankedstructure(1) Whenearthterminationsin built-upareaspassthrougha tankedstructure,a sealsimilartothatshownin Figure7.23shallbeused.7.18.4.6 Corrosion(1) Becauseof theharmfulcorrosionwhichis likelyto result,cokebreezeshallnotbeallowedto be in contactwith copperelectrodesandsaltingof thegroundin thevicinityof anyearthelectrodeis not recommended.7.19 COMMON EARTHING7.19.1CommonEarthPotential(1) All earthingmediumsin or onastructureshallbeinterconnectedtoprovideacommonearthpotential.(2) TheProvisionin (1) aboveshallincludelightningprotection,electricservice,telephoneandantennasystemearthsas well as undergroundmetallicpiping systems;main size lightningconductorsshallbeusedfor interconnectingtheseearthingsystemsto thelightningprotectionsystem.7.19.2CommonEarthBonding(1) If electric,teiephone,or othersystemsareearthedto a commonearthingterminal(seeFigure 7.24),oneconnectionfromthelightningprotectionsystemto theterminalis required.(2) If the servicesystemsare earthedto a metallicWlJ,terpipe;only one connectionto thelightningsystemis requiredprovidedthatthewaterpipeis electricallycontinuousqetweenallsystems.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 192SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION(3)If thewaterpipein (2) aboveis notcontinuous,thenon-conductivesectionsshallbebridgedwithmainsizeconductors,or theconnectionshallbemadeatapointwhereelectricalcontinuityisassured.7.20 USEOF REINFORCING BARSFOR EARTHING IN CONCRETE STRUCTURES7.20.1General(1)Detailonhowtouseconcretereinforcingbarsshallbeworkedoutatthedesignstagebeforebuildingconstructionbegins(seeClauseB.6, AnnexB).7.20.2Electrical(;;ontinuity(1)Electricalcontinuityof thereinforcementshallbeensured.(2) Thefollowing precautionsare,however,recommended:a) Goodcontactbetweenreinforcingbarsshouldbeensured;i.e,by fixingbarswith tyingWIres.b) Ties shallbeprovidedfor bothverticalto verticalandhorizontalto verticalbars.7.20.3PrestressedConcreteMembers(1)Lightningprotectionconductorsshall not be connectedto prestressedconcretecolumns,beamsor braceswherethe wires or strandsare_not linked and, therefore,not electricallycontinuous.7.20.4PrecastConcreteMembers(1)In thecaseof precastreinforcedconcretecolumns,beamsor braces,thereinforcementmaybeusedas a conductorif the individualelementsof reinforcementarebondedtogetherandelectricalcontinuityis ensured.193 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS7..-21 STRUCTURAL STEEL FRAMING FOR LIGHTNING PROTECTION7~21.1Gene..,.1(:1) Thestrocturalsteelfr{l1lleworkofa buitdingmay be usedas the main conductorof ,alightningprotectiOIisystemif it is eitherelectricallycontinuousor madeso.1.21.2 Air Termination(I) Air terminationshallbe bondeddirectlylothe steelframeworkor by conductorsleadingthroughtheridges,roof,or copingwalls,or connectedtogetherwithaconductorontheexteriorof the buildingthatis bondedto thesteelframework.(2) If leI(QIIe)(b)1(d)(alSECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONNote: i) Lightningconductorfixingsshouldbepurpose-madeforeachsizeofstrip;dimensiona inFigure(e)shouldbeequalto thethicknessof thestripandshouldbe equalto thewidthplus 1.3mma forexpansion.Conductorsof circularsectionshouldhesimilarlytreated.ii) All fixingsshouldbesecurelyattachedtothestructure;mortarjointsshouldnotbeused.Figure 7.1 Typical designfor lightningconductorfixings195 EBCS-101995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSHCGL~///////////// GLPI.n viewPI.n vl.w01Ion. 01--- ...... 01lont 01protection --/' ' prottctlontt ground/'...../ tt groundI, / 'I Ilvtl/ (IHeIve 00 I.I I / IZP / ZP'- /---- ............/---(t) Ont Vlnlc.' conductor lbl Horllonttl tlr t.rmlnttlonIcl Four vortlcolconductorsshowingprotlctlVl .ngl.nd soclttedIon 01protection.oveove,.-- -''/ ........... '/ ZP ZP { vC vC o 0 Jprotection.t ground .,...,Figure7.2 Protectiveanglesandzonesof protectionforvariousformsof air terminationETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 196SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONFigure7.3 Typicalformsof verticalair termi~ations197 EBCS-10 1995 ETHIOPIAN BUILDINGCODI; STANDARDELECTRICAL INSTALLATION OF BUILDINGS-$-4 D_n conductora Horlzontl'conductora Tilt lolnt4---i1u.CEP~:Earth10-113! KIY1Air tormlnll .~13~t32 Rodholdliitl~3 Rodcoupling'Q7 Elnh Ilectrodl67III Chimney.'II thin 1.5mdlomettrIt top.ond20mhil'6Ql Ib6. EII'thtod'A' cllmp9 RodhOUllnl10 Cond'ctorclip(bl60mbricl(ltlck11 cOronllbind12 BondtoCI' 'roncapII.'tornatltocoronllbind1111.13 JunctioncllmpNote This figure,doesnot applyto reinforcedconcretechimneyswherethereinforcingbarscanbeusedasdownconductorsFigure7.4 Examplesof lightningprotectionsystemsfor brickchimneysETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 198SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONBimetellicjointReinforcedconcreteIlructurewith parapet,Ilonecopingandnon-conductingroofGalvanizedsteel roofBonds tosteelworkBond to metalsuspendedceilingReinforcedconcrete structure,PVC coping withconducting roof34Key 1 Handrailbond2 Reinforcingbond3 Copingbond4 Non-ferrousbondingpoint(built-in)4One reinforcing ber shown for clarityDetailshowingitem4Figure7.5 Examplesof air terminationsand down conductorsusinghandrails,metalcopingsandreinforcingbars.199 EBCS-10 1995 ETHIOPIAN BUILDING ,CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS___ Bolted jointconnecti on 2M 8BeamNote: Minimum dimensionswhena metallicroof coveringis usedaspartof theair terminationnetworkareasfollows:galvanizedsteelcopperaluminiumIO.5mmO.3mmO.7mmzincleadO.7mm2.0mmFigure 7.6 Air terminationfor flat roof sbowingconnectionto standingseamjointwhena metallic roof is usedas part of tbe air terminationnetworkETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 200SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION 'HC ,/:s:j l~',Ie) Elevation.howingprotective.ngleHC' 'Oml mall.l//--_/20mLIIHCIHCI,I . I IIHe___ ZP_Ib) Plan.howlngzoneof protectionatgroundlevelIc) Gen.rel.rrangement]figure7.7 Air terminationsfor a flat roof201 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSNote: i) If S>10+2H,additionallongitudinalconductorsarerequiredsothatthedistancebetweenconduc~rsdoesnotexceedlO:Om.ii) If thelengthof theroofexceeds20.0m,additionaltransverseconductorsarerequired.iii) Downconductorsareomittedforclarity.Figure 7.8 Air terminationsfor largeareasof roof various profilesETHIOPIAN BUILDING CODE STANDARD EBCS-1 0 19~5 202SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONTestjointDC'IIIIIIIIIDeL(1)16 mDCTestjoint .......20 m(2) (3)16 mTestjointDC16 mNote: Theprotectiveangleprovidedbytheridgeconductorin eachcaseis asfollows:(i) protectiveangleupto45: ridgeconductorissufficientwithconnectiontometallicgutters;numberofdownconductors=72/20=3.6(say4).(ii) protectiveangleover45~:air terminationmesh(maximumIO.Omx (IO+2H));ridgeandeavesconductorsprovideapproximateroofmesh6.0mx lQ.Om;numberof downconductors=40/20=2.(iii) situationasfor (ii) butmetallicguttersusedin lieuofeavesconductor;numberof downconductors=64/20=3.2(say4).(a) Air terminations'an'downconductorsD.t.1IRfdge conductorfixed below tile-'e~el(see detail)Conductor'orstrip rOd ormetallicgulterVertical airterminatinnKey: Concealdconducto~ O.3mhighbarverticalrods.(b) Air terminationsbelowroofcoveringFigure7.9 Air terminationsandconcealedconductorsfor buildingsless20.0mhighwithstoppingroofs203 EBCS-10 1995 ETHIOPIAN BUILDING QODE STANDARDSectionAAELECTRICAL INSTALLATION OF BUILDINGSPerimeter24 +24 + 12+ 1272 m Numberof downconductonrel.1Iired72/204.-Join downconductor.andhorizontalconductorson lowerparapet.'-,,-, ,,-'.....- ,..ViewfromBDCI[J IIt [J I HellIl-ocAOC~ II-. -#---r112l6m J./III Afa Dc'112m.. 6m .1Note: i) An.airtenninationalongtheouterperimeterof theroofis requiredandnopartshouldbemorethan5.0mfromthenearesthorizontalconductor,exceptthatanadditional1.0mmaybeallowedforeachmetrebywhichthepartto beprotectedis belowthenearestconductor.ii) Horizontalconductorsarenotnecessaryontheparapetsofthelightwell;azoneofprotectionof60isprovidedbythetwoadjacenthorizontalconductorsforstructureslessthan20.0mhigh.Thisprincipledoesnotapplyto tallerstructures.Figure7.10 Air terminationsfor flat roofsatdifferentlevelsETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 204Note: i) Horizontal air tenninationconductorsshouldbejointed at the interconnections.Figure 7.12Air terminationsfor tall conductingstructuresETHIOPIAN BUILDING CODE STANDARDEBCS-10 1995::[ OM' El-I ... DC 60 m DC .../?ECTION 7: EARTHING, BOND1NGAND LIGHTENING PROTECTIONii) WherePVC coveredhorizontalair tenninationconductorsareused,bareverticalrodsO.3mhigh shouldbe fixed at eachintersectionandat intennediatepositionsalongthehorizontalconductorsspacednomore than 10apart.205Note: The air tenninationnetworkfor a tan reinforcedconcreteor steelframedstructureshouldbe as fonows:(a) Horizontal conductorson roofs from a IO.Omx 20.0mnetwork.(b) Therearebondsto steelworkatcorners,at20.0mintervalsaroundtheperipheryandonthetowerO.5mabovethe lower roof level.(c) Key bondingto thebuilding steelwork.Figure 7.11Air terminationsand down conductorsfor flat roof buildings where the airterminationconductorshavea PVC oversheathELECTRICAL INSTALLATION OF BUILDINGSRoof conductor*representsa bondto roof steelwork.Note: i) The horizontalconductormeshsize shouldbe 5.0mx 1O.Omor smaller,accordingto the risk.ii) For clarity, down conductorsareomitted.Figure 7.13 Air termination network with horizontal conductorsfor structure withexplosiveor highlYJlammable contentsETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 206SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONSmFl't n,:p conductorf.lt.n.dtoplnp.t willI IIi,,I,,I,t, ,99 9 I,I!,.9I' -.Koy~ on metal roofs, theseconductorsmay be omitted.1 Air termination2 Down conductor3 Bonds to holding dowp rod4 Horizontal conductor5 Vertical conductor6 Ridge conductor7 Eavesconductor8 Test point9 Earth electrode10 Main earthingterminalof Electrical installation11 Bond to bell-frame12 PeripheralconductorNote: i) The air terminationnetworkshouldhavea 1O.Oll} x20.0mmesh.For structuresbelow20.0mhight,thereshouldbedownconductorsevery20.0mof peripheryand for structuresover20.0mhigh, every10.0mof periphery;horizontalconductorsshouldbe every20.0mfrom the top.ii) Metal roofs may be suitableasair terminations(seeTable 7.5 andFigure 7.17).iii) On shinglespires,metallic soakersandgullies shouldbe bondedat the top andbottom.Figure7.14 Churchtowersandspires207 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSMastSuspended air terminationSee note 2See ,note 2Protected buildingSee note 2~Earth electrode~lat Elevation- Suspended air terminationProtect.ed buildingSuspended air termination(b}PlanKayProtectedbuilding(el End .I .llon showingzones01proteSECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONR RilclillSof bolnd.8 inchus (203 mOll minimlim.Figure7.16 Sharpbends209 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSNt ,. -----.L ldli1.1 I.Ibl 1.1T3:LJ= 11/Itl leiNote: i) Thedownconductorsmaybenaturalpartofthebuildingframeworkoraddedstripsorrodsonexternalfaces.ii) On structuresexceeding20.0minheight,downconductorsshouldbespacedatnotmorethan1O.Omapart.Figure7.17 Patternof downconductorsforvariousformsof tall buildingETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 210l ~SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONad maximum Exceeding ad, d' i'~(aIPermissible arrangement (bl Arrangamant that is not permissiblelcl Permissible melhod of taking conductorthrough a pllrapat wallFigure7.18Re-entrantloops211 EBCS-10 1995Not II Ipermissible--t ~PermisslbletIldl Routlli for,down conductor' in a buildingwith cantilevlIrtlduppllr lIoonETHIOPIAN BUILDING CODE STANDARDELECTRICAL. INSTALLATION OF BUILDINGSA= o.6~m mini~umtB= 3.0P m mini~Um.Figure 7.19 Earthtng in ~oiBtClay ~oil.Figure7.19 Earthingin moistclaysoilETHIOPIAN BUILDING CODE STANDARDEBCS-10 1995 212Ground levelBonds to lift installationsat top and bottom ofcontinuousrigid metalstructure onlyAir termination on roofDownconductorslin these caSessteel rei,.forc ingor steel frameof buildingIAi,. termination bondedto steel reinforcing orsteel frome of buildingII~ Earth electrodeNOTE. Air tenninationmeshshouldbe not.eat. tun 10m X 20 m. Downconductorsshouldbe not moretNn 10m ~art.(~, IJJ 111111l ELECTRICAL INSTALLATION OF BUILDINGSternate configurationA =10.610 mminimuma = 13.00m minimumFigure 7.21 Earthing in sandyor gravelysoilETHIOPIAN BUILDING CODE STANDARD EBCS-10 1'995 214SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTION,/,/--ELECTRICAL INSTALLATION OF BUILDINGS..~0'. 0, .0 o ',. ' 0Concrete 0,,'o. 0:. b, 'o.... ,~'. 0 ,, , . D ,0. ,b,~ ' ,P ,Asphalt0, .' ., 1I ':0111 0:,'.'0. ~'.' ,4 '-' :*:1.',0Asphalt /'Concrete1ft}!..-~/;~,??-.~/.;?:~~~,~:';:~:i'.0. 6' :. ?, 'n.'Figure 7.23 Example of an earth electrodesealfor usewithin a tanked structureETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 216~',,.... 11,.0: ,ETHIOPIAN BUILDING CODE STANDARD, ...-, t kI 0' ( ' t 1#'(- , I ' , ,,.J' ',......' ,,,.., ,.. I ~, l' ,., ...i- ,,~..I,ExterMl downconductor..-..-For cavity lallSprovfde sea ed tubeTest Jo nt~INOTE. Corrosion inhibitor to be used on allGasLightning protectionearth termination netv~Electr~city cableWaterSECTION 7: 'EARTHING, BONDING AND LIGHTENING PROTECTIONEBCS-10 1995217Figure 7.25 TestingjointsFigure 7.24 Diagram showingbondingto services(gas,water and electricity)ELECTRICAL INSTALLATION OF BUILDINGSBondingplate with aminimumcontact area'of 52 sq. mmA :::O.61m minimumB = 3.00m minimumFigure7.26 EarthingconnectiononstructuralframingETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 218ANNEX A (INFORMA11VE)SYSTEM DESIGNGENERAL CONSIDERATIONSThestructureor, if it hasnot beenbuilt, thedrawingsandspecificationsshouldbe examinedtakinginto accounttherecommendationsof thisSection.In thecaseof structureshavingno suitablemetallicmembers,it is importantto considert~positioningof all thecomponentpartsof a lightningprotectionsystemsothattheyperformtheirfunctionwithoutdetractingfromtheappearanceof thestructure.Modernbuildingsusemetalextensivelyin theirstructureandthereis considerablebenefitinutilizingsuchmetalpartsto maximizethe numberof parallelcon~uctingpaths. Often thelightningprotectionwill be improved,worthwhilecostsavingsmay resultand the aestheticappearanceof the structurepreserved.However,it shouldbe bornein mindthata lightningstriketo sucha metalpart,especiallyif it is beneaththesurface,maydamagethecoveringandcausemasonryto fall. This'risk can be reduced,but not eliminated,by a surface-mountedlightningprotectionsystem.Examplesof metalpartswhichshouldbeincorporatedintolightningprotectionsystemsaresteelframes,concretereinforcingbars,metalinoronaroof,windowrailsandhandrails.Somemetalwithina structuremaybeusedasa componentof thelightningprotectionsystem;for example,.sheetpiling beingin contactwith thegeneralmassof earth,maybeusedasanearthelectrodeandis unlikelyto be improveduponby theadditionof rodsor tapes.Thewholestructureshouldbeprovidedwithafully interconnectedlighteningprotectionsystem;i.e.,no partof thestructureshouldbeprotectedin isolation.219 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDANNEX B (CONSULTATION)B.t GENERALConsultationshouldtakeplacebetweenthedesignerof thelightningprotections'ystemandtheinterestedpartiesindicatedin ClausesB.2 throughB.6 beforeandduringall stagesof design.B.2 ARcmTECT / ENGINEERAs far aspracticable,thefollowingshouldbedetennined:a) Routingof ,illlconductors.b) Generalareasavailablefor earthtenninationnetworksandreferenceearthelectrodes.c) Materials(s)for conductor.d) Extentof the work andthe division of responsibilityfor primaryfixings to thestructure,especiallythoseaffectingthewater-tightnessof thefabric,chieflyroofing.e) Materials(s)to be usedin the structure,especiallyfor any continuousmetal,e.g.stanchionsor reinforcing.f) Use to whichthestructureis to beput.g) Detailsof all metallicservicepipes,rain-watersystem,railsandthelike enteringorleavingthestructureor withthestructurewhichmayrequirebondingtothelightningprotectionsystem.h) Extentof anyburiedserviceswhichcouldaffectthesitingof theearthtenninationnetwork(s).i) Detailsof anyequipment,apparatus,plantor the like to be installedwithin or nearthebuildingandwhichrequirebondingto thelightningprotectionsystem.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 220SECTION 7: EARTHING, BONDING AND LIGHTENING PROTECTIONB.3 PUBLIC UTILITIESAgreementshouldbe reachedon thebondingof servicesto the lightningprotectionsystem.Becauseof the introductionof newmaterialsandpractices,relianceshouldnot be placedonagreementsreachedfor otherstructures.B.4 FIRE AND SAFETY OFFICERSAgreementshouldbereachedon:a) the needfor a lightningprotectionsystemon structurescontainingflammableorexplosivematerials;b) routesand materials(s)for constructionof ductsand sealingat floors if internalconductorarebeingconsidered;c) themethodof lightningprotectionto beadoptedin theunlikelyeventof a structurehavinga flammableroof.B.5 TELEVISION AND RADIO INSTALLERSAgreementshouldbereachedontheneedto bondantennasupportsandscreensof cablesto thelightningprotectionsystem.B.6 BUILDERAgreementshouldbereachedon:a) theform, positionsandnumbersof primaryfixingsto beprovidedby thebuilder;b) anyfixingsprovidedby thelightningprotectionsystemcontractorto be installedbythebuilder;c) thepositionsof conductorto beplacedbeneaththestructure;d) whetheranycomponentsof thelightningprotectionsystemaretobeusedduringtheconstructionphase,e.g.thepermanentearthterminationnetworkcouldbeusedforearthingcranes,railwayline,scaffolding,hoistsandthe like duringconstruction;221 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGSe) for steelframedstructures,thenumbersandpositionsof stanchionsandtheform offixing to bemadefor theconnectionof earthterminations;f) whethermetallicroof covering,whereused,are suitableas partof the lightningprotectionsystemandthemethodof attachmentof conductorto earth;g) thenatureandlocationof servicesenteringthe structureaboveandbelowgroundincludingrailwaylines,cranerails,wireropeways,conveyorsystems,televisionandradioantennasandtheirmetalsupports,metalflues,andflue-liners;h) thepositionandnumberof flag-masts,roof levelplantrooms(i.e.,lift motorrooms,ventilating,tanksandothersalientfeatures;i) theconstructiontobeemployedfor roofsandwallsin orderto determineappropriatemethods of fixing conductor, specifically with a view to maintainingtheweather-tightnessof thestructure;j) possiblepenetrationof awaterproofingmembranewhereearthterminationshavetobesitedbeneaththestructure,especiallyin 'urban'situationsandin confinedspac.~son industrialsites;Note: The samegeneralconsiderationappliesto the referenceearthelectrodefor use in initial andperiodictesting.k) theprovisionof holesthroughthestructures,parapets,cornices,etcto allow forthefreepassageof thedownconductor;I) theprovisionof bondingconnectionsto a stedframe,reinforcementbarsandothermetal;m) the mostsuitablechoiceof metalfor the conductortakingaccountof corrosion,especiallyatbimetalliccontacts;n) theaccessibilityof testjoints, protectionby non-metalliccasingsfrom mechanicaldamageor pilferage,loweringof flag-mastsor otherremovableobjects,facilitiesforperiodicinspection,especiallyon chimneys;0) thepreparationof adrawingincorporatingtheabovedetailsandshowingthepositionsof all conductorsandof themaincomponents.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 222SECTION 8WIRING METHODS8.1 SCOPE(1) This Sectionappliesto all wiring installationoperatingat0.6/1.0kVor lessexceptfor:(a) conductorswhich forman integralpartof factorybuiltequipment;(b) communicationcircuit,unlessotherwisespecifiedin Section23;(c) Class2 circuits,unlessotherwisespecifiedin Section10;(d) communityantennadistribution,radio and televisioninstallations,unlessotherwisespecifiedin Section24;(e) opticalfiber cables.8.2 NORMATIVE REFERENCE(1) Thefollowingreferencescontainprovisionswhich,throughreferencein.thistext,constituteprovisionsof theEthiopianBuilding CodeStandardon ElectricalInstallationof Buildings.(a) C22.1:1992(b) BS 767:1992CanadianElectrical Code Part I, Safety Standardfor ElectricalInstallation,SixteenthEditionThe electriciansGuide to the 16th Edition of the lEE WiringRegulations,SecondEdition, 19938.3 GENERAL REQUIREMENTS8.3.1 Methods of Installation(1) The methodsof installationof wiring systemsshallbeasshownin AnnexA.. ETHIOPIAN BUlLDING CODE STANDARD EBCS-l0 1995 223ELECTRICAL INSTALLATION OF BUILDINGS(2) The Provisionsin (1) abovenotwithstanding,theuseof anothermethodis not precludedprovidedthatcompliancewiththisCodeis maintained(3) A barelive conductorshallbe installedon insulators.(4) Non-sheathedcablesfor fixed wiring shallbe enclosedin conduits,ductingor trunking;however,thisprovisiondoesnotapplyto a protectiveconductor.8.3.2 Wiring in Ducts and Plenum Chambers(1) No electricalequipment,unlessspecificallyapprovedfor thepurpose,shallbe installedinductsusedto transportdust,loosestock,or flammablevapours.(2) No electricalequipment,unlessspecificallyapprovedfor thepurpose,shallbe installedinanyductusedfor vapourremovalor for ventilationof commercial-typecookingequipment.8.3.3 Underground Installations(1) Directburiedconductors,cables,or racewaysshallbeinstalledto meettheminimumc?verrequirementsshownin Table8.1.Table 8.1 Minimum coverrequirementstfor direct buriedconductors,cablesor racewaysMinimum cover [mm]Wiring methodNon-vehicular area.Vehicular area.750.0VorOver 750.0V750.0VorOver 750.0VIeIeConductors or cables600750900.1000not having a metal sheath Qr armourConductors or cables4507506001000having a metalsheath or armourRaceway4507506001000Minimum covermeansthedistancebetweenthetopsurfaceof theconductor,cable,orracewayandthefinishedgrade.224 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 8: WIRING METHODS(2)The minimumcoverrequirementsshall be permittedto be reducedby IS0.0mmwheremechanicalprotectionis placedin thetrenchovertheundergroundinstallation.(3) Mechanicalprotectionshallconsistof oneof thefollowingand,whenin flat form,shallbewideenoughto extendat leastSO.Ommbeyondtheconductor,cables,or racewayson eachside:(a) Treatedplankingat least38.0mmthick.(b) Pouredconcreteat leastSO.Ommthick.(c) Concreteslabsat leastSO.Ommthick.(d) Concreteencasementat leastSO.Ommthick.(e) Otheracceptablematerial.(4)Racewaysor cables,if locatedin rock,maybeinstalledatashallowerdepthentrenchedintotherock in a trenchnot lessthanIS0.0mmdeepandgroutedwith concreteto the levelof therocksurface.(5)Racewaysmay be installeddirectlybeneatha concreteslab at gradelevel providedtheconcreteslabisnotlessthananominal1OO.Omminthickness,thelocationis adequatelymarked,andtheracewaywill notbesubjectto damageduringor afterinstallations.(6)Any form of mechanicalprotectionwhich mayadverselyaffectthe conductorsor cableassembliesshallnotbeused.(7) Backfill containinglargerock,pavingmaterials,cinders,largeor sharplyangularsubstances,or corrosivematerialshallnot be placedin an excavationwheresuchmaterialsmaydamagecables,raceways,or othersubstructurespreventadequatecompactionof fill, or contributetocorrosionof cables,raceways,or othersubstructures.8.3.4 Conductorsin Hoistways(2) The cable,conduit,or tubingreferredto in (1) aboveshallbe:(1) Whereconductorsotherthanthoseusedto fumishenergyto the lift or dumbwaiterareinstalledin hoistways,theyshallbefrommineral-insulatedcableor armouredcablesor berunin rigid or flexiblemetalconduitor electricalmetallictubing.(a) securelyfastenedto thehoistwayconstruction;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 225ELECTRICAL INSTALLATION OF BUILDINGS(b) arrangedsothatterminal-outletsorjunctionboxesopenoutsidethehoistwayexceptthatpull boxesmaybe installedin long runsfor thepurposeof supportingor pulling inconductors.(3) (a) Main feedersfor supplyingpowertoelevatorsanddumbwaitersshallbeinstalledoutsidethehoistway.(b) Only suchelectricwiring, raceways,andcablesuseddirectlyin connectionwith theelevatoror dumbwaiter,includingwiring for signals,for communicationwith thecar,for lighting,heating,air conditioningandventilatingthecar,shallbepermittedinsidethehoistway.8.4 CONDUCTORS8.4.1 Typesof Conductors(1) Conductorsinstalledin anylocationshallbe suitablefor theconditionof useas indicatedin AnnexB of Section4 for theparticularlocationinvolvedandwith particul.arrespect..to thefollwing(a) moisture(b) corrosiveaction(c) temperature(d) degreeof inclosure(e) mechanicalprotection.8.4.2 Radii of Bendsin Conductors(1) The minimuminternalradii of bendsin conductorsshallbeasindicatedin Table8.2r226 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 8: WIRING METHODS227EBCS-10 1995Type of Insulation OveralldiameterBendingfactorPVCup to 10.0mm3 (2)PVC10.0m to 25.0mm4 (3)PVCover 25.0mmaMineralany diametreatETHIOPIAN BUILDING CODE STANDARD(a) in junctionboxeswhichare locatedat leastl.Omabovegradeandsecuredto buildingsor to stubpolesandsuitablyprotectedfrommechanicaldamage;(b) notwithstandingtherequirementsin (3) above,by meansof splicingdevicesor materials(kits) acceptablefor directearthburial.(1)Unlessmadewith solderlesswire connectors,jointsor splicesin insulatedconductorsshallbesoldered,buttheyshallfirst bemademechanicallysecured.Table8.2 Minimuminternalradiiof bendsin cablesfor fixedwiringNote: i) The factorshownin thetableis thatby whichtheoverallcablediametermustbemultipliedto give theminimum inside'radiusof the bend.ii) The figutesin bracketsapplyto unsheathedsingle-corestrandedpye cableswhen.installedin conduit,trunkingor ducting.Mineral-insulatedcablesmaybebentataminimumradiusof threetimesthecablediameterprovidedthattheywill only be bentonce.(4) Splicesin undergroundrunsof cable,if requireddueto damageto theoriginalinstallation,maybemade:'.(2) Joints or splicesshallbe coveredwith an insulationequivalentto thaton the conductorsbeingjoined.8.4.3 ConductorJoints andSplices(3) Jointsor splicesin wiresandcablesshallbeaccessible.,IELECTRICAL INSTALLATION OF BUILDINGS8.4.4 Supportingof Conductors(1) Conductorsshallbesupportedsothatno injuriousstrainis imposedontheterminalsofanyelectricalapparatusor devicesor onjoints or taps. Table8.3showsguidanceon methodsofsupport.Table8.3Spacingof supportsfor cablesin accessiblepositionI: I~MBximumsp,cing of clips [mm]Ov',11 di,mBt' ofShllthBd c,bllS1-Min',f.insul,tBd c,bllSc,blB [mm] IHorizontalVerticalHorizontalVertical:5;9250400600800>9 :5;15300400900121)0>15 ~ 2035045015002000>20 ~ 40400550Note: For thespacingof supportsfor cablesof overalldiameterexceeding40.0mm.andfor single-corecableshavingconductorsof cross-sectionalarea300.0mm2andlarger,themanufacturer'srecommendationsshouldbe observed. '.8.5 OPEN WIRING8.5.1 OpenandClippedDirect.(L) Sheathedcablesclippeddirectto or lying on non-metallicsurfaceshall be installedinaccordancewith InstallationMethod1(seeAnnexA).8.5.2 Spacingof Conductors(1) Spacingbetween conductorsand adjacentsurfacesshall be as indicatedin InstallationMethods12and13(seeAnnexA).(2) In all locations,aseparationof atleast25.0mmshallbemaintainedbetweenconductorsandadjacentmetalpipingor conductingmaterials.228 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 8: WIRING METHODS8.5.3 ConductorSupports(1)Conductorsshallbesupportedrigidlyon noncombustible,absorptionresistinginsulators.(2)Conductorssupportedon solid knobsshall be securelytied theretoby tie wires havinginsulationof thesametypeasthatontheconductorswhichtheysecure.8.5.4 Spacingof Supports(1)Sheathedand/ or armouredcablesinstalledin accessiblepositionsandsupportedby clipsshallnotexceedtheappropriatespacingvaluestatedin Table8.3.8.6 EXPOSED WIRING ON EXTERIOR OF BUILDINGS AND BETWEENBUILDINGS ON THE SAME PREMISES8.6.1 Locationof Conductors(I) Whereconductorsare supportedon or in close proximityto the exteriorsurfacesofbuildings,theyshallbeinstalledandprotectedsothattheyshallnotbehazardousto personsorbeexposedto mechaniELECTRICAL INSTALLATION OF BUILDINGS8.7 BARE BUS BARS AND RISERS(1) Bare conductorsshall not be usedas mainrisersor feedersin buildingsunless,specialpermissionis obtained.(2) Specialpermissionshallnotbegrantedunless:(a) thebuildingis of noncombustibleconstruction;(b) theconductorsareplacedin a chase,channel,or shaftlocatedor guardedso thattheconductorsareinaccessible;(c) thepremisesdo notconstitutea hazardouslocation;(d) suitablecut-offsto protectagainsttheverticalspreadof fire areprovidedwherefloorsarepierced;(e) themechanicalandelectricalfeaturesof theinstallationandtheconductorsupportsareappropriateto theoperatingandmaintenanceconditionslikely to occur,thefollowingrequirementsbeingusedin thecaseof busbarsratedl200.0A or less:Note: i) Where flat busbars6.25mmor lessin thicknessareused,thecontinuouscurrentratingshallnotexceed1.6A/mm2of cross-sectionalareaof copperbusbaror 1.12A/mm2in thecaseof aluminiumbus bars.ii) Bus bar supportsshallbe spacednot morethan750.0mmapart,with minimumclearanceacrossinsulatingsurfacebetweenbarsof oppositespolarityof notlessthan50.0mm,and25.0mmbetweenbus barsandany earthedsurface.8.8 INSTALLATION OF BOXES, CABINETS, OUTLETS AND TERMINALFITTINGS8.8.1 Number of Outlets per Circuit(1) Thereshallbenomorethan12outletson any2-wirebranchcircuitexceptaspermittedbyotherSectionsof thisCode.(2) Suchoutletsin (1) aboveshallbe consideredto beratedatnot lessthan1.0A per outletexceptaspermittedby (3) below.(3) Wheretheconnectedloadis known,thenumberof outletsmayexceed12providedtheloadcurrentdoesnotexceed80%of theratingof theovercurrentdeviceprotectingthecircuit.230 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 8: WIRING METHODS8.8.2 OutletBoxes(1)A boxor anequivalentdeviceshallbe installedateverypointof outlet,switchor junctionofconduitandateverypointof outletandswitchof concealedkllob-and-tubework.(2)Nonmetallicoutletboxesshall not be used in wiring methodsusing metal raceways,armouredor metalsheathedcable,exceptwheretheboxesareprovidedwithbondingconnectionbetweenall conductorentryopenings.(3)Thebox shallbeprovidedwith a coveror a fixturecanopy.(4)At least150.0mmof free conductorshall be left at eachoutletfor makingof joints 'orconnectionof fixturesunlesstheconductorsareintendedto loopthroughlampholders,socketoutlets,or similardeviceswithoutjoints.(5)Ceilingoutletboxesin concreteslabconstructionshallhaveknockoutsspacedabovethefreeor loweredgeof theboxesa distanceof atleasttwicethediameterof thesteelreinforcingbarssothatconduitenteringtheknockoutsshallclearthebarswithoutoffsetting.(6)Boxesandfittingsshallbe firmly securedto studs,joistsor similarfixed structuralunits.8.8.3 Conductorsin Boxes(1)Boxes shall be of sufficientsize to provideusablespacefor all insulatedconductorscontainedin thebox.(2)Conductorswhich areconnectedto differentpoweror distributiontransformersor otherdifferentsourcesof voltageshallnotbe installedin thesamebox,cabinetor fitting.8.8.4 TerminalFittings(1)Whereconductorsarerunfromtheendsof conduit,armouredcablesurfaceracewaysor nonmetallicsheathedcableto appliancesor openwiring installation,an outletfittingor terminalfittingmaybeusedinsteadof theboxrequiredin Clause8.8.2,andtheconductorsshallberunwithoutsplice,tapor joint withinthefitting.(2)The fittingsin (1) aboveshallhavea separatelybushedholefor eachconductor.(3)The fittingsin (1) aboveshallnotbeusedatoutletsfor fixtures.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 231ELECTRICAL INSTALLATION OF BUILDINGSL8.9 CABLES, CONDUCTORSAND WIRING METHODS(1) Every cableoperatingatlow voltageshaHbeselectedin accordancewith Section4 of thisCode.(2) The methodof installationof cablesandconductorsshallbe subjectto the provisionofClause8.3.1.1232 E13cs-101995 ETHIOPIAN BUILDING CODE STANDARDANNEX A (NORMATIVE)SCHEDULE OF METHODS OF INSTALLATION OFCABLESNote: i) The methodsof installationdistinguishedby bold type are referencemethodsfor which the current-carryingcapacitygiven in Annex B, TablesB.I throughB.45, Section4, havebeendetermined.ii) For the othermethods,an indicationis givenof theappropriatereferencemethodhavingvaluesofcurrent-carryingcapacitywhich can safelybe applied.Installationmethod AppropriateReferenceMethodExamplesfor determiningNumber current-carryingDescription capacity12 342Openand clipped direct:Sheathedcablesclippeddirectto or lying : ~on a non-metallicsurface'. ~Cables embeddeddirect in buildingmaterials:Sheathed cables embedded directly inmasonry,brickwork,concrete;plasterorthe like (otHerthan thermallyinsulatingmaterials)In conduit:11~J~Method 1Method 1345Single-core non-sheathed cables inmetallicor non-metallicconduiton a wallor ceilingSingle-core non-sheathed cables inmetallic or non-metallic conduit in athermally insulating wall or above athermally insulating ceiling, the conduitb~ing in contact with a thermallyconductivesurfaceon one sidetMulticore cables having non-metallicsheath,in metallicor non-metallicconduiton a wall or ceiling.Method 3Method4Method 3tThe wall is assumedto consistof anouterweatherproofskin,thermalinsulationandaninnerskinof aplasterboardor awood-like materialhavinga thermalconductancenot lessthanIOw/m2K.The conduitis fixed soasto becloseto, butnot necessarilytouching,the innerskin. Heatfrom thecablesis assumedto escapethroughthe innerskinonly.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 233ELECTRICAL INSTALLATION OF BUILDINGSNumber67In trunking:8910On trays:InstallationmethodDescription2Sheathedcablesin conduitin athermally insulating wall etc.(otherwiseasReferenceMethod4)Cables in conduitembeddedinmasonry,brickwork,concrete,plaster or the like (otherthanthermallyinsulatingmaterials)Cables in trunkingon a wallorsuspendedin theairCablesin flushfloortrunkingSingle-core cable in skirtingtrunkingExamples3lc:Qp..- --'-, , .AppropriateReferenceMethodfor determiningcurrent-carryingcapacity4Method4Method3Method3Method3Method311 Sheathedcablesonaperforatedcable tray, bunched andunenclosed.A perforatedcabletray is consideredas a trayinwhichtheholesoccupyat least30%of thesurfaceareaMethod 11In freeair, on cleats,bracketsor a ladder12Shathedsingle-corecablesinfree air (any supportingmetalwork ';'Ider the cablesoccupyingless than10%of theplanarea):Two or thr'lecablesverticallyone abovethe other,minimum distance betweencable surfaces equal tc, theoverall cable diameter (D.);distancefromthe wall not lessthan0.50.Twoorthreecableshorizontally,with spacings as abovethreecables in trefoil, distancebetweenwall and surface ofnearestcable 0.50.or nearestcables0.750.Method 12234 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 8: WIRIN.G METHODSNumberInstallationmethodDescriptionExamplesAppropriateReferenceMethodfor determiningcurrent-carryingcapacity2 3 4In freeair, oncleats,bracketsor a ladder1314Sheathedmulticorecablesonladderor brackets,separationgreaterthan20. Sheathedmulticorecables infree air distancebetweenwall andcablesurfacenotlessthan0.3D.Anysupporting metalwork under thecablesoccupyingless than10%theplanareaCables suspended from orincorporatinga catenarywire~ (~[Method 13Method12or 13,asappropriate15 Method 4Method4Wherethecablehasadiameter D. or aperimeternot greaterthan200.Method3Where the duct haseither a diametergreaterthan50. or aperimetergreaterthan200.Notes:--i-) Wheretheperimeteris greaterthan 600.,installation Methods18 to 20, asappropriate,shouldbeused.~(Sheathedcables In ducts or voidsformed by the building structure,other than thermally insulatingmaterials16Cablesin buildingvoids:-----------Sheathedcablesinstalleddirectlyina thermallyinsulatingwallor abovea thermallyinsulatingceiling, thecable being In contact with athermallyconductivesurfaceononeside(otherwiseas RefMethodNo4)Ii) D. is the overallcable diameter; forgroupsof cablesD. isthe sum of the cablediameters.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 235ELECTRICAL INSTALLATION OF BUllDtNGSInstallationmethodExamples.Number I DescriptionAppropriateReferenceMethodfor determiningcurrent-carryingcapacity2CableIn trenches:3 417181920Cables supportedon thewallof anopenorventilatedtrench,withspacin~as indicatedforReferenceMethod12or 13asappropriateCables in enclosed trench450.0mmwide by 300.0mmdeep (minimumdimensions)including100.0mmcovera ~ ~ ~~n~r;p~ ?;,#l ~ r;_.LL F/. /L / /// //'a------t0-9/),/9/~Cables in enclosed trench450.0mmwide by 600.0mmdeep (minimumdimensions)including100.0mmcoverCables in enclosed trench600.0mmwide by 760.0mmdeep (minimumdimensions)including100.0mmcover~ V;;]0 0 o~~o 0 o~~o 0 ov.:~o 0 o~/ ////////,Twosingle-corecableswithsurfaces separated by aminimum of one cablediameter.Threesingle-corecables intrefoil and touchingthroughout.Multicorecablesor groupsof single-corecables withsurfaces minimum of50.0mmSingle-corecablesarrangedin flatgroupsoftwoor threeontheverticaltrench wall with surfacesseparatedby one diameterwitha minimumdistance'of50.0mmbetweengroups.Multicore cables installedwithsurfacesseparatedbyaminimum!of 75.0mm.Allcables spaced at least25.0mmfromthetrenchwallSingle-corecablesarrangedin groupsof twoor threeinflat formation with thesurfacesseparatedby onediameter or intrefoilformation with cablestouching.Groups separated by aminimum!of 75.0mmeitherhorizontallyorvertically.All cables spaced at least25.0mmfromthetrenchwall.Method12or 13,asappropriateMethod18.Use ratingfactorsin TableA.3,Section4.Method19.Use ratingfactorsin TableA.3,Section4;Method20.Use ratingfactorsinTableA.3,Section4.! Largerspacingto beusedwherepracticable.236 EBCS-10 1995 ETHIOPIAN BUilDING CODE STANDARDSECTION 9PROTECTION AND CONTROL9.1 SCOPE(1) This Sectioncoverstheprotectionandcontrolof electricalcircuitsandapparatusinstalledin accordancewith therequirementsof thisCode.9.2 NORMATIVE REFERENCES(I) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) C22.1:1992(b) BS 7671:1992CanadianElectricalCode Part I, SafetyStandardfor ElectricalInstallation,SixteenthEdition.Requirements for Electrical Installation,IEE .WiringRegulations,SixteenthEdition.9.3 GENERAL REQUIREMENTS9.3.1 ProtectiveandControlDevices(1) Every electricalapparatusandunearthedconductorsshall be protectedby one or moredevicesasmaybenecessaryfor automaticand/ormanualinterruptionof thesupplyin theeventof anyfaultandshallbeprovidedwith:(a) protectionagainstfaultcurrentto breakanyfaultcurrentin acircuitbeforesuchcurrentcausesdangerdueto thermalor mechanicaleffectsproducedin thoseconductorsor theassociatedconnection;(b) protectionagainstoverloadcurrentto breakany suchcurrentflowing in the circuitconductorsbeforesucha currentcausesa temperaturerise detrimentalto insulation,joints, terminationor thesurroundingsof theconductors;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 237ELECTRICAL INSTALLATION OF BUILDINGS(c) protectionagainstunder-voltagewhichwhennecessarywill openthecircuit,whereareductionin voltage,or lossandsubsequentrestorationof voltagecouldcausedanger;(d) manually-operablecontroldevicewhichwill safelydisconnectall unearthedconductorsof thecircuitatthepointof supplysimultaneously;and(e) protectionagainstearthfaultin accordancewith Clause9.4.2.9.3.2 Types and Ratings of Protectiveand Control Devices(1) Circuitbreakers,fuses,andswitchesshallbeof typeandratingsacceptabletothedepartmentin chargeof inspection.(2) Overcurrentprotectivedevicesshall ensuresafe operationand shall have interruptingcapacitysufficientfor thevoltageemployedandfor theanticipatedfaultcurrentwhichmllstbeinterrupted.9.4 PROTECTIVE DEVICES9.4.1 OvercurrentDevices(1) Each unearthedconductorshallbeprotectedby anovercurrentdeviceatthepointw.?ereitreceivesits supplyof currentandateachpointwherethesizeof conductoris decreased,exceptthatsuchprotectionmaybeomittedwhere:(a) theovercurrentdevicein a largerconductorproperlyprotectsthesmallerconductor;(b) thesmallerconductoris notover3.0mlonganddoesnotextendbeyondtheswitchboard,panelboard,controldevicewhichit supplies;or(c) thesmallerconductorhasanampacitynotlessthanone-thirdthatof thelargerconductorfrom which it is supplied.(2) The ratingor settingof overcurrentdevicesshallnotexceedtheallowableampacityof theconductorswhichtheyprotectexcept:(a) wherea fuse or circuit breakerhavinga ratingor settingof the samevalueas theampacityof theconductoris notavailable,theratingsor settingsgivenin Table9.1maybeused;(b) in caseof equipmentwire, flexiblecord,andtinselcord,whichwill be consideredasbeing protectedby 16.0Aovercurrentdevices;or(c) asprovidedfor by otherClausesof thisCode.238 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 9: PROTECTION AND CONTROL(3)Overcurrentdevicesshallbeenclosedin cutoutboxesor cabinetsunlesstheyformapartofanapprovedassemblywhichaffordsequivalentprotection,or unlessmountedon switchboards,paneboards,or controllerslocatedin roomor enclosuresfreefromeasilyignitiblematerialanddampness,andaccessibleonly to authorizedpersons.(4)Overcurrentdevicesshallnotbeconnectedin parallelin circuitsof 1000.OVor lessunlessotherwisetheyarefactory-assembledin parallelasa singleunit.9.4.2 Earth-FaultProtection(1)Earth-faultprotectionshallbeprovidedtode-energizeall normallyearthedconductorsof afaultedcircuit in theeventof anearthfaultin thoseconductorsasfollows:(a) in solidlyearthedcircuitsratedmorethan230.0V-to-earth,lessthan1000.OVphase-to-phaseand 1000.OAor more;and(b) in solidlyearthedcircuitsrated230.0V-to-earthor lessand2000.0Aor more.(2)Themaximumsettingof theearth-faultprotectionshallbe l200.0Aandthemaximumtimedelayshallbe 1.Osfor earthfaultcurrentsequalto or greaterthan3000.0A.~ -(3)Theampereratingof thecircuitsreferredto in (1) aboveshallbeconsideredto be:(a) theratingof thelargestfusethatCanbe installedin a fusibledisconnectingdevice;(b) the highesttrip settingfor which the actualovercurrentdeviceinstalledin a circuitbreakeris ratedor canbeadjusted;or,)c) the ampacityof the main.conductorfeedingthe devicesin caseswhere no maindisconnectingdeviceis provided.'(4)Earth-faultprotectionshallbeprovidedby,:v(a) anovercurrentdevic~which incorporatesearth-faultprotection;1)/v(b) earth-faulttrippi.ngsystem.comprisinga senso~or sensors,relayandauxiliarytrippingmechanism;or./(c) otherappropriatemeans.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 239J..ELECTRICAL INSTALLATION OF BUILDINGS9.5 FUSES(1) Only fusesand fuse holdersof properratingshall be used,and no bridging or shortcircuitingof eithercomponentshallbepermitted.(2) Whereplug fusesareusedin branchcircuits,theyshallbe of sucha typeandso installedthattheyarenon-interchangeablewith a fuseof largerrating.(3) A fusehavinga fuse link which is likely to beremovedor replacedwhile thesupplyisconnectedshallbeof a typesuchthatit canberemovedor replacedwithoutdanger.9.6 CIRCUIT BREAKERS(1) Circuit breakersshallbeof thetrip-freetype.(2) Indicationshall be providedat thecircuitbreakerandat thepointof operationto showwhetherthecircuitbreakeris openor closed.(3) Circuit breakersshallopenthecircuitin all unearthedconductorsby themanualoperationof a singlehandleandby theactionof overcurrent.(4) Circuit breakersshallbeof suchdesignthatanyalterationbytheuserof eitherthetrippingcurrentor thetimewill bedifficult.(5) 'circuitbreakersshallbeequippedwith trippingelementsasspecifiedin Table9.2.9.7 CONTROL DEVICES(1) Controldevicesshallhave'ratingssuitablefor theconnectedloadof thecircuitswhichtheycontroland,withtheexceptionof isolatingswitches,shallbecapableof safelyestablishingandinterruptingsuchloads.(2) Control devicesusedin combinationwith overcurrentdevicesor overloaddevicesfor thecontrolof circuitsor apparatusshallbeconnectedsothattheovercurrentor overloaddeviceswill bedeadwhenthecontroldeviceis in theopenposition,exceptwherethis is impracticable.(3) Controldevices,with theexceptionof isolatingswitches,shallbereadilyaccessible.240 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 9: PROTECTION AND CONTROL(4) Controldevices,unlesslocatedor guardedsoasto rendertheminaccessibletounauthorizedpersonsandto preventfire hazards,shallhaveall current-carryingpartsin enclosuresof metalorotherfire-resistingmaterial.(5) Whereelectricalequipmentis suppliedby two or moredifferenttransformersor othersourcesof voltage,then:(a) a single disconnectingmean~,which will effectivelyisolateall unearthedconductorsupplyingtheequipment,shallbeprovidedintegralwith or adjacentto theequipment;or(b) each supply circuit shall be providedwith a disconnectingmeansintegralwith oradjacentto theequipment,andthedisconnectingmeansshallbegroupedtogether.9.8 SWITCHES(1) Single-throwknife switchesshallbe mountedwith theirbasesin a verticalplaneso thatgravitationalforcewill nottendto closethem.(2) (a) Double-throwknife switchesmaybemountedsothatthethrowwill be eitherverticalor horizontal.(b) If thethrowin (1) aboveis vertical,a positivelockingdeviceor stopshallbeprovidedtoensurethatthebladesremainin theopenpositionwhensosetunlessit is notintendedthattheswitchbe left in theopenposition.(3) Manualsingle-throwswitches,circuitbreakers,or magneticswitches,shallbeconnectedsothatthebasesor movingcontactswill be deadwhenthedeviceis in theopenpositionexceptwhenotherconditionsmakethisrequirementunnecessary. '9.9 PROTECTION AND CONTROL OF MISCELLANEOUS APPARATUS.(1) Socketoutletsshallnotbeconnectedto abranchcircuithavingovercurrentprotectionratedor setatmorethantheampereratingof thesocketoutletsexceptaspermittedby otherSectionsof thisCode.(2) Portable appliancesneed not be equippedwith additionalcontrol deviceswhere theappliancesare:ETHIOPIAN BUILDING CODE STANDARD EBCS~10 1995 241ELECTRICAL INSTALLATION OF BUILDINGS(a) mtedatnotmorethan1500.0W;and(b) providedwith cordconnectors,attachmentplugsor othermeansby whichtheycanbedisconnectedreadilyfromthecircuits.(3)Whereswitchesare usedto controlan outletor outletsfrom morethanone point, theswitchesshallbewiredandconnectedsothattheearthedconductorrunsdirectlyto theoutletor outletscontrolledby theswitches.(4) Exceptfor panelboardswheremorethan90%of theovercurrentdevicessupplyfeedersormotorbranchcircuits,everypanelboardshallbeprotectedon thesupplysideby overcurrentdeviceshavinga ratingnotgreaterthanthatof thepanelboard.(5) Transferequipmentfor standbypowersystemsshallpreventtheinadvertentinterconnectionof normalandstandbysourcesof supplyin anyoperationof thetransferequipment.242 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 9: PROTECTION AND CONTROLTable9.1 Ratingor settingof overcurrentdevicesprotectingconductors(For generalusewherenot otherwisespecificallyprovidedfor)Ampacity of Rating or setting permitted [A]conductorsFuseCircuit breaker0-16161617-20202021-25253226-32323233-40404041-50505051-63636364-808010091-100100100101-110110125111-125125125126-150150150151-175175175176-200200200201-225225225226-250250250251-275300300276-300300300301-325350350326-350350350351-400400400401-450450450451-500500500501-525600600526-550600600551-600600600ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 243tTable9.2 Overcurrenttrip coilsfor circuitbreakersa~doverloaddevicesfor protectingmotorsFor circuit protection t For motor overload protectionNumber and Icoation ofNumber and location of overloadovercurrentdevices (Trip Coils)Systemdevices such as trip coils relays, orKind of motorthermal cutouts3-tripcoils,one ineachconductor3-wire,3-phasea.c.,unearthedor with3one in eachphasenotto beearthedneutralcqpnectedin anyneutralconductor3-phasea.c.3-tripcoils,one ineachphase4-wire,3-phasea.c.2-tripcoils,one eachphase4--wire,2-phasea.c.,unearthed2one in eachphase,notto be 2-phasea.c.connectedinanyneutralor earthed2-tripcoils,one ineachoutside3-wire,2-phasea.c.conductorconductor4-tripcoils,one ineachunearthed4-wire,2-phasea.c.,withearthedneutralconductor4-tripcoils,one ineachunearthed5-wire,2-phasea.c.conductor2-tripcoils,one ineachoutside3-wire,1-phasea.c.or d.c.1in anyconductorexcepta neutralor 1-phasea.c.or d.c.1-tripcoil ineachunearthed2-wirea.c.or d.c., unearthedor withoneearthedconductorconductorconductorearthedtt2-tripcoils,one ineachunearthed3-wire,1-phasea.c. or d.c.,withearthedconductorneutralThiswill notprecludetheuseof otherarangementswhichwill provideequivalentprotection.tt Thiswill notpreventtheuseof onesingle-polecircuitbreakerin eachconductorfor theprotection.of anunearthed2-wirecircuit.SECTION 10CLASS 1 AND CLASS 2 CIRCUITS10.1 SCOPE(1) This Sectioncoversremote-control,signallingandpower-limitedcircuitsthatarenotintegralpartsof a deviceor anappliance.(2) This Sectiondoesnotapplyto communicationcircuitsthataredealtwith in Section23.Note: The circuitsdescribedin thisSectionarecharacterizedby usageandpowerlimitationwhich differentiatethemfromelectriclightandpowercircuitsand,therefore,alternativerequirementsto'thoseof otherrelevantSectionsof thisCodewithregardtominimumwiresizes,de-ratingfactors,overcurientprotection,insulationrequirements,wiring method,andmaterialare deemednecessary.10.2 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) NFP A70/NEC:1986 NationalFireProtectionAssociation!AmericanNationalElectricalCode,1987Edition.(b) C22.I:199210.3 CLASSIFICATION10.3.1GeneralCanadianElectricalCode Part I,Safety Standardfor ElectricalInstallations,SixteenthEdition.{i)CirCUItscoveredbythisSectionarethoseportionof thewiringsystembetweentheloadsideof theovercurrentdeviceor thepower-limitedsupplyandall connectedequipment,andshallbeClass1 or Class2 asdefmedbelow:(a) Class 1 - Circuitswhicharesuppliedfrom sourceshavinglimitationin accordancewith Clause10.4.1.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 245ELECTRICAL INSTALLATION OF BUilDINGS(b) Class2 - Circuitswhich aresuppliedfrom sourceshavinglimitationin accordancewith Clause'10.5.1.10.3.2Class1Extra-Low-VoltagePowerCircuits(1) Circuitswhichareneitherremote-controlcircuitsnor signalcircuits,butwhich operateatnot morethan30.0V wherethecurrentis not limitedin accordancewith Clause10.5.1andwhicharesuppliedfromatransformeror otherdevicerestrictedin itsratedoutputto 1000.OVAshall be clasefiedas extra-low-voltagepowercircuitsand shallbe consideredto be Class1circuits.10.3.3Class 2 Low-EnergyPowerCircuits(1) Circuitswhichareneitherremote-controlcircuitsnorsignalcircuitsbutin whichthecurrentis limitedin accordancewith Clause10.5.1shallbeclasified aslow-energypowercircuitsandshallbe consideredto beClass2 circuits.10.3.4HazardousLocation(1) Wherethecircuitsor apparatuswithinthescopeof this Sectionareinstalledin hazardouslocations,theyshallalsocomplywith theapplicableClausesof Section12.10.3.5Circuitsto SafetyControlDevices(1) Wherethefailureto operatearemote-controlcircuittoasafetycontroldevicevrill introducea directfire or life hazard,theremote-controlcircuitsshallbedeemedto bea Class 1circuit.10.3.6Circuitsin CommunicationCables(1) Class1 circuitsshallnotberun in thesamecablewith communicationcircuits.(2) Class2 remote-controlandSignalCircuitsor partsthereofwhichuseconductorin a cableassemblywith otherconductorsformingpartsof communicationcircuitsare,for thepurposeofthis Code, deemedto be communicationcircuitsand shall conformto the req~irementsofapplicableClausesof Section23.246 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 10: CLASS 1 AND CLASS 2 CIRCUITS----10.4 CLASS 1CIRCUITS10.4.1Limitationof Class1Circuits(1)Class1 extra-low-voltagepowercircuitsshallbe suppliedfrom a sourcehavinga ratedoutputof not morethan30.0V and 1OOO.OVA.(2)Class I remote-controland signal~ircuitsshall be suppliedby a sourcenot exceeding600.0V.10.4.2Methodsof Installationfor Class1Circuits(1)The equipmentandconductorof Class I circuitsshallbe installedin acc?rdancewith therequirementsof otherappropriateSectionsof thisCode,exceptasprovidedinClauses10.4.5through10.4.10.10.4.3OvercurrentProtectionof Class1Circuits(1)Conductorsof Class 1 circuitsshallbe protectedagainstovercurrentin accordancewithSection9 of thisCode,except:(a) where other Clausesof this Code specificallypermitor requireother overcurrent.protection;or(b) wheretheconductorsareof 1.0mm2copperandextendbeyondtIleequipmentenclosure,theyshallbeprotectedby overcurrentdevicesratedata maximumof 5.0A and 10.0A,respectively.(2) Whereovercurrentprotectionis.installedatthesecondaryterminalsof thetransformerandthetransformeris suitablyenclosed,no overcurrentprotectionis requiredon theprimarysideothttrthanthenormalovereurrentprotectionof thebranchcircuitsupplyingthetransformer.10.4.4Locationof OvercurrentDevicesin ClfSs1Circuits(1) In Class1circuits,theovercurrentdevicesshallbe locatedatthepointwheretheconductorto beprotectedreceivesits.supply.(2) The overcurrentdevicemaybean integralpartof thepowersupply.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 247ELECTRICAL INSTALLATION OF BUILDINGS10.4.5Class1Extra-Low-VoltagePowerOrclIit SourcesIncludingTransformers(1) To complywith the 1OOO.OVA limitation,Class1 extra-low-voltagepowercircuitsourcesincludingtransformersshallnotexceed'amaximumpoweroutputof 2500.0VA; andtheproductof themaximumcurrentandmaximumvoltageshallnotexceedlOOOO.OVA withtheovercurrentprotectionby-passed.10.4.6ConductorMaterialandSizes(1) Copperconductorssmallerthan2.5mm2maybeusedin Class1circuitsif:~(a) installedin a raceway;(b) installedin a cableassembly;or(c) within a flexiblecord in accordancewith Section4.6.(2) Subjectto theconditionsspecifiedin (1) above,conductorsshallnotbesmallerthan:a) 1.5mm2for individualconductorspulledin raceways;b) 1.0mm2for individualconductorslaid in raceways,andc) 1.0mm2for an integralassemblyof two or moreconductors.10.4.7InsulatedConductorsfor Class1Wiring(1) Whereconductorslargerthan1.5mm2copperareusedin a Class1circuit,theyshallbeofanytypeshownin AnnexB of Section4.(2) Whereconductorof 1.0mm2or 1.5mm2copperareusedin a Class1 circuit,theyshallbeequipmentwire of thetypesuitablefor suchuseasshownin AnnexB of Section4.10.4.8Conductorsof DifferentCircuitsin theSameEnclosure,Cable,or Raceway(1) DifferentClass1circuitsshallbepermittedtooccupythesameenclosure,cableor racewaywithout regardto whetherthe individualcircuitsare alternatingcurrentor direct current,providedall conductorsare insulatedfor the maximumvoltageof any conductorin theenclosure,cableor raceway.(2) Power supplyconductorsandClass1circuitconc'uctorsshallnotbepermittedin thesameenclosure,cable,or racewayexceptwhenconnectedto thesameequipment;andall conductorsareinsulatedfor themaximumvoltageof anyconductorin theenclosure,cable,or raceway.248 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 10: CLASS 1 AND CLASS 2 CIRCUITS10.4.9MechanicalProtectionof Remote-ControlCircuits(1)Wheremechanicaldamageto aremote-controlcircuitwouldresultin ahazardousconditionallconductorsof suchremote-controlcircuitsshallbe installedin conduits,electricalmetallictubing,or beotherwisesuitablyprotectedfrommechanicalinjuryor otherinjuriousconditionsuchasmoisture,excessiveheator corrosiveaction.lO.4.10 Class1 CircuitsExtendingAeriallybeyonda Building(I) Class1circuitswhichextendaeriallybeyonda buildingshallcomplywiththerequirementof Section 8.6.10.5 CLASS 2 CIRCUITS10.5.1Limitationsof Class2 Circuits(1)Class2 circuits,dependinguponthevoltage,shallhavecurrentslimitedasfollows:a) 0 to20.OV: Circuitsin whichtheopen-circuitvoltagedoesnotexceed20.0V shallhaveovercurrentprotectionratedat not morethan5.0A exceptthatovercurrentprotection.shallnotberequiredwherethecurrentis suppliedfrom:i) primarybatterieswhich, undershortcircuit,will not supplya currentexceeding7.5A after 1.0min;ii) a Class2 circuittransformer;iii) a devicehavingcharacteristicswhichwill limit thecurrentundernormaloperatingconditionsor underfaultconditionsto a valuenotexceeding5.0A; oriv) a devicehavinga Class2 output.b) Over20.0V butnotexceeding30.0V: Circuitsin whichtheopen-circuitvoltageexceeds20.0V, but doesnot exceed30.0V, shall havean overcurrentprotectionratingnotexceeding lOON amperes,where V is the open-circuitvoltage, except that the,overcurrentprotectionshallnotberequiredwherethecurrentis suppliedfrom:i) primarybatterieswhichundershortcircuitwill notsupplyacurrentexceeding5.0Aafter 1.0min;ii) a C;:lass2 circuittransformer;iii) a devicehavingcharacteristicswhichwill limit thecurrentundernormaloperatingconditionsor underfaultconditionsto avaluenotexceedinglOON amperes,whereV is theopen-circuitvoltage;oriv) a devicehavinga Class2 output.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 249ELECTRICAL INSTALLATION OF BUILDINGSc) Over30.OJ' butnotexceeding60.0.,,:Circuitsin whichtheopencircuitvoltageexceeds30.0V. but does not exceed60.0V, shall have an.,overeurrentprotectionratingnotexceedinglOON ampers,whereV istheopen-circuitvoltage,exceptthattheovercurrentpro~ectionshallnotberequiredwherethecurrentis suppliedfrom:i) a Class2 circuittransformer;orii) a devicehavingcharacteristicswhichwill limit thecurrentundernormaloperatingconditionsor underfaultconditionsto avaluenotexceedinglOON amperes,whereV is theopen-circuitvoltage.d) Over60.0'butnotexceedingJ 50.0.,,:Circuitsinwhichtheopen-circuitvoltageexceeds60.0V, but doesnot exceedISO.OV,shall havean overcurrentprotectionratingnotexceedinglOON amperes,whereV is theopen-circuitvoltage,and,in addition,shallbeequippedwith current-limitingmeansotherthanovercurrentprotection,whichwill limitthecurrent,eitherundernormaloperatingconditionsorunderfaultconditions,to avaluenot exceedinglOON amperes,whereV is theopen-circuitvoltage.(2) TransformerdevicessupplyingClass2 circuitsshallberestrictedin theirratedoutputto notexceedingI OO.OVA.(3) A devicehavingenergy-limitingcharacteristicsmayconsistof a seriesresistorsof suitableratingor othersimilardevice.(4) A Class 2 powersupplyshallnot be connectedin seriesor parallelwith anotherClass2powersource.10.5.2MethodsofInstallationonSupplySideofOvercurrentProtectionor Transformersor OtherDevicesfor Class2 Circuits(1) In Class 2 circuits, the coriductorsand equipmenton the supply side of overcurrentprotectidh,transformers,or current-limitingdevicesshallbe installedin accordancewith therequirementsof otherappropriateSectionsof thisCode.10.5.3Marking(1) A Class2 powersupplyunit shallhavepermanentmarkingswhich shallbereadilyvisibleafterinstallationto indicatetheclassof supplyanditselectricalrating.10.5.4OvercurrentProtectionfor Class2 Circuits(1) Overcurrentprotectionof differentratingsshallnotbeof an interchangeabletype.250 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 10: CLASS 1 AND CLASS 2 CIRCUITS(2)The overcurrentprotectionmaybean integralpartof a transformeror otherpower-supplydevice.10.5.5Locationof OvercurrentDevices(1) Overcurrentdevicesshallbelocatedatthepointwheretheconductortobeprotectedreceivesitssupply.10.5.6Conductorsfor Class2 CircuitWiring(1) ConductELECTRICAL INSTALLATION OF BUILDINGSshallnotbeplacedin anyraceway,compartment,outletbox,junctionboxor similarfittingwiththeconductorof electriclighting,poweror ClassI circuits.10.5.8ConductorsofDifferentClass2Circuitsin theSameCable,Enclosure,orRaceway0) Conductorsof two or more Class 2 circuitsshall be permittedwithin the samecable,enclosureor racewayprovidedall conductorsin thecable,enclosure,or racewayareinsulatedfor the maximumvoltageof anyconductor.10.5.9Penetrationof a Fire Separation(1) Conductorsof a Class2 circuitextendingthrougha fire separationshallbeso installedasto limit fire spread.10.5.10Conductorsin VerticalShaftsandHoistways(1) Class2 conductorsmldcableinstalledin averticalshaftor hoistwayshallcomplywith therequirementsof Section18.10.5.11Class2 ConductorsandEquipmentin DuctsandPlenumChambers(1) Class2 conductorsandequipmentshallnotbeplacedin ductsor plenumchambersexceptaspermittedby Clause8.3.2.10.5.12EquipmentLocatedontheLoadSic;leofOvercurrentProtection,Transformers,orCurrent-LimitingDevicesfor Class2 Circuits(1) Equipmentlocatedon the load sideof overcurrentprotection,transformers,or current-limitingdevicesfor Class2 circuitsshallcomplywiththefollowing:a) For Class2 circuitsoperatingat30.0V or less,alternatingcurrentor directcurrent,itshallbeacceptablefor theparticularapplication.b) For Class2 circuitsoperatingatmorethan30.0V,alternatingcurrentor directcurrent,it shall bearrangedsothatno livepartsareaccessibleto unauthorizedpersons.(2) Notwithstandingtheprovisionsof (Ia) above,lightingfixturesandthermostatsincorporatingheatanticipators,locatedon the load sideof overcurrentprotection,Class2 transformers,orcurrent-limitingdevicesshallbeapprovedwhenconnectedtoClass2 circuitsoperatingat30.0Vor less.252 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 10: CLASS 1AND CLASS 2 CIRCUITS10.5.13 Class2 CircuitsExtendingBeyonda Building(1)WhereClass2 circuitsextendbeyonda buildingandarerun in sucha manneras to besubjectedto accidentalcontactwith lighting or power conductorsoperatingat a voltageexceeding380.0V betweenconductorsof the Class 2 circuits, they shall also meet therequirementsof Section23.10.5.14 UndergroundInstallations(1)Undergroundinstallationsof Class 2 circuits shall be installedin accordancewithClause8.3.3.(2)DirectburiedClass2 circuitsshallmaintainaminimumhorizontalseparationof 300.0mrrlfromotherundergroundsystemsexceptwheninstalledin accordancewith (3) below.(3)DirectburiedClass2 circuitsmaybeplacedatrandomseparationin a commontrenchwithpowercircuitswhicharefor thesolepurposeof supplyingpowerto theClass2 circuitsprovidedthattheClass2 circuit is in a metalsheathed'cable,with sheathbondedto earth,the powercircuitoperatesat750.0Vor less,andall conductorsareinsulatedfor themaximumvoltageofanyconductorin thetrench.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 25311.1 SCOPEINSTALLATIONSECTION 1rECTRICAL'UIPMENT(1) This Sectionappliesto theinstallationof thefollowingelectricequipment:a) Heatingandcooking.b) Submersiblepump.c) Motorsandassociatedcircuits.d) Air conditioning.e) Refrigerating.f) Storagebatteries.11.2 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) NFPA 70/NEC:1986 National Fire Protection Association!American NationalElectricalCode,1987Edition.(b) C22.1: 199011.3 GENERAL11.3.1FusibleEquipmentCanadianElectricalCode,Part 1,SafetyStandardfor ElectricalInstallations,SixteenthEdition.../(1) Fusible equipmentshall employlow-melting-pointfuseswhenconnectedto conductorswhoseampacityis basedonAnnexB of Section4, unlessequipmentusingothertypesof fusesis markedasbeingsuitablefor suchuse.254 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT11.3.2Connectionto IdentifiedTerminalsor Leads(1) Wherevera devicehavingan identifiedterminalor leadsis connectedin a circuithavingidentifiedconductors,theidentifiedconductorsshallbeconnectedto theidentifiedterminalorlead.11.3.3EquipmentoverCombustibleSurfaces(1) Wherethereis acombustiblesurfacedirectlyunderstationaryor fixedelectricalequipmentlthatsurfaceshallbecoveredwith a steelplateat least1.6mmthickandwhichshallextendatleast150.0mmbeyondtheequipmenton all sides,if:a) theequipmentis markedto requiresuchprotection;orb) theequipmentis openon thebottom.11.3.4Installationof VentilatedEnclosures(1) Yentilatedenclosuresshallbe installedin sucha mannerthatventilationis not restricted.11.3.5OutdoorInstallations(1) Outdoorinstallationsof apparatus,unless'housedin suitableenclosures,shallbesurroundedby suitablefences.(2) Outdoorequipmentshallbebondedto ~arthin anacceptablemanner.11.4 ELECTRIC HEATING AND COOKING APPLIANCES11.4.1Locationof Non-PortableAppliances(1) Non-portableelectricheatingandcookingappliancesshallbe installedso thatthedangerof ignitingnearbycombustiblematerialsis reducedto a minimum.11.4.2Ratingof PortableAppliances(2) The inputto portableelectricheatingandcookingappliancefor useon nominal230.0Ybranchcircuitsprotectedby overcurrentdevicesratedor setatnotmorethan16.0Ashallnotexceed1500.0Wat230.0Y.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 255ELECTRICAL INSTALLATION OF BUILDINGS11.4.3ApplianceExceeding1500.0W(1) Everyelectricheatingandcookingapplianceratedatmorethan1500.0Wshallbesupplied. fromabranchcircuitusedsolelyfor oneapplianceexceptthatmorethanoneappliance.maybeconnectedto a single-branchcircuitprovidedthatfollowingis used:a) A multiple-throw,manually-operateddevicethatwill permitonlyonesuchappliancetobeenergizedatonetime;orb) An automaticdevicethatwill limitthetotalloadto avaluethatwill notcauseoperationof theovercurrentdeviceprotectingthebranchcircuit.(2) Everyelectricheatingandcookingapplianceratedatmorethan1500.0Wshallbecontrolledby an indicatingswitchwhichmaybe in thecircuitor on theapplianceexceptthat:a) if the ratingof theappliancedoesnot exceed32.0A,an attachmentplug and socketoutletmaybeusedinsteadof a switch;andb) if the appliancehasmorethanone individualheatingelementeachcontrolledby aswitch,no mainswitchneedbeprovided.Note: For thepurposedof thisClause,twoormoreseparatebuilt-in cookingunits,togetherwith theirovercurrentdevices,ar~consideredasone appliance.11.5 HEATING EQUIPMENT(1) All electricpowerfor heatingandassociatedequipmentoperatingin connectiontherewithshallbe obtainedfroma single-branchcircuitwhichshallbeusedfor no otherpurpose.(2) A suitabledisconnectingmeansshallbeprovidedfor thefeederor branchcircuit.11.6 SUBMERSmLE PUMPS(1) Powersupplyconductorsor cablesrunfromwell-headto thepump(deepwell submersiblepump)shallbe:a) rubber(thermoset)insulatedcable,thermoplastic-insulatedcable,singleconductorsor twistedassembliesof thistypes;orb) extra-hardusagetype,or theequivalentportablecable.256 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT(2) The areaaroundthe submersiblepump installedin lakes,rivers and streamsshall beprotectedfrom accessby thepublicby fencing,cribbingor isolationandso marked.11.7 MOTORS AND ASSOCIATED CIRCUITS11.7.1 Wiring MethodsandConductors11.7.1.1Stationarymotors(1) The wiring methodfor stationarymotorsshall be in accordancewith the applicablerequirementsof Section8.11.7.1.2PortableMotors(1) Connectionsto portablemototsshallbe permittedwith flexiblecordwhich shallhaveaserviceabilitynot lessthanthat of extra-hardusagecord unlessthe motor forms part of amotor-operateddevice.11.7.1.3Motorsupplyconductorinsulation,temperaturerating,andampacity(1) Supplyconductorsto a motorconnectionbox shallhavean insulationtemperatureratingsequivalentto or greaterthanthoseprovidedin Table 11.1unlessthemotoris markedotherwiseandtheirampacitybasedon a75Cconductorinsulationratingwhen90Cwire is usedascircuitconductorsto themotor.(2) Where Table 11.1requiresinsulationtemperatureratingsin exc~ssof 75C, the motorsupplyconductorsshall not be lessthan1.2mlongandshallterminatein a locationnot lessthan600.0mmfromanypartof themotorexceptthat,for motorsrated100.0hpor larger,theirterminationsshallbenot lessthan1.2mfrom anypartof themotor.(3) For ambientshigherthan30C,thesupplyconductorinsulationratingshallbe increasedatleastby thedifferencebetweentheambientand30C.11.7.1.4 Conductorsto individualmotors(1) The conductorsof a branchcircuit supplyinga continuous-dutymotor shall have anampacitynot lessthan125%of thefull-loadcurrentratingof themotor.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 251ELECTRICAL INSTALLATION OF BUILDINGS(2) The conductorsof a branchcircuit supplyinga non-continuous-dutymotorshall haveanampacitynot lessthanthecurrentvalueobtainedby multiplyingthefull-loadcurrentratingofthemotorby theapplicablepercentagegivenin Table 11.2for thedutyinvolved.(3) NotwithstandingtheProvisionsof (1) above,conductorampacitiesshallbepermittedto beselectedfrom Table 11.5usingthefull-loadcurrentratingfor a continuousdutymotor.(4) Tap conductorssupplyingindividualmotorsfroma singlesetof branchcircuitovercurrentdevicesupplyingtwo or moremotorsshallhavean ampacityof at leastequalto thatof thebranchcircuit conductorsexceptthatwherethetapconductorsdo not exceed7.5min length,theyshallbe permittedto be sizedin accordancewith (1) or (2) aboveprovidedtheampacityso determinedis not lessthan% of theampacityof thebranchcircuitconductors.11.7.1.5 Conductors- twoor moremotors(1) Conductorssupplyinga groupof two or moremotorsshallhaveanampacityequalto orexceeding:(a) 125%of thefull-loadcurrentratingof themotorhavingthelargestfull loadclllTCntratingplusthefull loadcurrentratingsof all theothermotorsin thegroupwhereallmotors'in thegrouparecontinuous-dutymotors;(b) thetotalof thecalculatedcurrentsdeterminedin accordancewith (a) abovefor eachmotorwhereall motorsin thegrouparenon-continuous-dutymotors;or(c) thetotalof thefollowing wherethegroupconsistsof two or moremotorsof bothcontinuousandnon-continuous-dutytypes:i) 125%of thecurrentof thecontinuous-dutymotorhavingthe largestfull loadcurrentrating;(ii) thefull-load currentratingsof all othercontinuousdutymotors;and(iii) the calculatedcurrentdeterminedin accordancewith (2) below for thenon-continuousdutymotors.(2) Wherethecircuitryis so interlockedasto preventall motorsof thegroupfromrunningatthesametime,thesiLeof theconductorsfeedingthegroupshallbepermittedto bedeterminedfor themotor,or groupof motorsoperatingatthesametime,havingthelargestratingselectedasdeterminedin (1) above.258 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT(3) Demandfactorsshall be permittedto be appliedif the characterof the motor loadingjustifiesreductionof the'ampacityof theconductorto lessthantheampacityspecifiedin (1)aboveprovidedthat:(a) theconductorshavesufficientampacityfor themaximumdemandload;and(b) theratingor settingof theovercurrentdevicesprotectingthemis in accordancewith11.7.2.3(4)below.11.7.1.6Feederconductors(l) Wherea feedersuppliesbothmotorloadsandotherloads,theampacityof theconductorsshallbecalculatedin accordancewith 11.7.1.4and11.7.1.5plustherequirementsof theotherloads.(2) Theampacityof atapfromafeedertoasinglesetof overcurrentdevicesprotectingamotorbranchcircuit shall notbe lessthanthatof thefeeder,exceptthattheampacityof thetapshaHbepermittedto becalculatedin accordancewith 11.7.1.4and11.7.1.5if thetap:(a) doesnotexceed3.0min lengthandis enclosedin metal;or(b) doesnotexceed7.5min length,hasanampacitynot lessthan Y3 thatof thefeederandis suitablyprotectedfrommechanicaldamage.11.7.1.7Secondaryconductors(1) Conductorsconnectingthesecondariesof woundrotormotorsto theircontrollersshallhaveampacitiesnot lessthan:(a) 125%of theratedfull loadsecondarycurrentfor continuous-dutymotors;or(b) the percentageof ratedfull lmid specifiedin Table 11.2for non-continuous-dutymotors.(2) Ampacitiesof conductorsconnectingsecondaryresistors'tot_heircontrollersshallnotbelessthanthatdetermine,-ELECTRICAL INSTALLATION OF BUILDINGS11.7.2 OvercurrentProtection11.7.2.1 Branchcircuitovercurrentprotection(1) Each unearthedconductorof a motorbranchcircuitshallbeprotectedby an overcurrentdevicecomplyingwith thefollowing:(a) A branchcircuitsupplyingasinglemotorshallbeprotected,exceptaspermittedby (c)below,by usinganovercurrentdeviceof ratingnotto exceedthevaluesin Table 11.4usingtheratedfull loadcurrentof themotor;(b) notwithstanding(a) above,Table 11.5shallbepermittedto beusedto selectthesizeof overcurrentdevicesrequiredfor a motorwherethefull loadcurrentratingof themotor is shownin theTable;(c) instantaneoustrip (magneticonly)circuitinterruptersshallbepermittedwhereappliedin accordancewith 11.7.2.5;(d) wheretheovercurrentdevicesasdeterminedin (a) abovewill notpermitthemotortostart,theratingor settingof theovercurrentdeviceshallbepermittedto be increasedas follows:(i) A non-timedelayfuse:- not in excessof 400% of the motorfull load currentfor fusesratedup to600.0A;or- not in excessof 300%of themotorfull loadcurrentfor fusesrated601to 6000A; or(ii) A timedelayfuseto a maximumof 225%of themotorfull loadcurrent;and(e) for a branchcircuit supplyingtwo or more motors,the rating or settingof theovercurrentdeviceshallnotexceedthemaximumvaluepermittedby 11.7.2.4.11.7.2.2 Overcurrentprotectionmarkedonequipment(1) Wherethe characteristicsandratingor settingof a branchcircuit protectivedevicearespecified in the marking of motor CGntrolequipment,they shall not be exceeded,notwithstandinganygreaterratingor settingpermittedby 11.7.2.1.260 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALlATION OF ELECTRICAL EQUIPMENT11.7.2.3Feederovt'rcurrentprotection(1) For a feedersupplyingmotor branchcircuitsonly, the ratingor settingof the feederovercurrentdevieeshallnotexceedamaximumvaluecalculatedby determiningthemaximumratingor settingof the overcurrentdevicepem.ittedby 11.7.2.1for that motor which ispermittedthehighestratedovercurrentdevicesof anymotorsuppliedbythefeeder,andaddingtheretothesumof thefull loadcurrentratingsof all othermotorswhichwill bein operationatthesametime.(2) (i) Wherea feedersuppliesagroupof motors,twoor moreof whicharerequiredto startsimultaneously,andthefeederovercurrentdevicesassetin accordancewith(1) aboveare not sufficientto allow the motorsto start,the ratingor settingof the feederovercurrentdevicesshallbepermittedto be increasedasnecessaryto a maximum.(ii) NotwithstandingtheProvisionsof (i) above,thepermittedincreaseshallnot exceedtheratingpermittedfor a singlemotorhavinga full loadcurrentratingnot lessthanthesumof thefull loadcurrentratingsof thegreatestnumberof motorswhich startsimultaneously,providedthis valuedoesnot exceed300% of the'ampacityof thefeederconductors.(3) Wherea feedersuppliesoneor moremotorbranchcircuitstogetherwith otherloads,therequiredovercurrentprotectionshallbe determinedby calculatingtheovercurrentprotectionrequiredfor themotor.circuitsandaddingtheretotherequirementsof theotherloadssuppliedbythefeeder.(4) Wherea demandfactorhasbeenappliedaspermittedin 11.7.1.5(3b),theratingor settingof theovercurrentdevices(s)pfotectinga feedershallnot exceedtheampacityof thefeeder,exceptaspermittedby applicableClausesof Section8.11.7.2.4GrfJupingof motorsona singlebranchcircuit(1) Two or moremotorsshallbepennittedto begroupedundertheprotectionof a singlesetof branchcircuit overcyrrentdeviceshavinga ratingor settingcalculatedin accordancewith11.7.2.3(1)providedthattheprotectionconformsto oneof thefollowing:(a) The ratingsor settingsof theovercurrentdevicesdonotexceed16.0A;or(b) Protectionis providedfor thecontrolequipmentof themotorsby havingthebranchcircuitovercurrentdevicesratedor setat:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 261ELECTRICAL iNSTALLATION OF BUILDINGS(i) valuesnotin excessof thosemarkedonthecontrolequipmentfor thelowestratedmotorof thegroup,assuitablefor theprotectionof thatcontrolequipment;or(ii) in the absenceof suchmarkings,valuesnot in excessof 400% of thefull-loadcurrentof thelowestratedmotor.(c) The motorsareusedon a machinetool or woodworkingmachine;and(i) the controlequipmentis arrangedso thatall contactswhich openthe motor'sprimarycircuitsarein enclosures,eitherformingpartof themachinebaseor forseparatemounting,having a wall thicknessnot less than 1.69mmfor steel,2.40mmfor malleablecastiron, or 6.30mmfor othercastmetal,havinghingeddoors with substantialcatches,and having no openingsto the floor or thefoundationon whichthemachinerests;and(ii) theratingsor settingsof theovercurrentdevicesdonotexceed200.0Aat230.0Vor less,or 100.0Aatvoltagesfromp1.0V to 750.0V.(d) All themotorsareoperatedby a singlecontroller.11.7.2.5 Instantaneous-tripcirettitinterrupters(1) Instantaneoustrip circuit interrupters,whenusedfor branchcircuitprotection,shallbe:(a) partof a combinationmotorstarteror controllerthatalsoprovidesoverloadprotection;and(b) ratedor adjusted,for ana.c.motor,to trip atnotmorethan1300%of themotorfull-loadcurrentor atnotmorethan215%of themotorlockedrotorcurrent,wheregiven,exceptthatratingsor settingsfor trip currentneednotbe lessthan16.0A;or(c) ratedor adjusted,for ad.c.motorratedat50.0hpor less,to tripatnotmorethan250%of themotorfull loadcurrent,or for a d.c.motorratedatmorethan50.0hp,to tripatnotmorethan200%of themotorfull-loadcurrent.11.7.3 OverloadandOverheatingProtection11.7.3.1 Overloadprotectionrequited(1) The branchcircuit conductorsandcontrolequipmentof eachmotorshall haveoverloadprotection,exceptaspermittedby 11.7.3.5262 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT11.7.3.2Typesof overloadprotection(1) Overloaddevicesshallbeeither:(a) a separateoverloaddevicewhich is responsiveto motorcurrentandwhich shall bepermittedtocombinethefunctionof overloadandovercurrentprotectionif it is capableof protectingthecircuitandmotorunderbothoverloadandshortcircuitconditions,(b) a protectivedevice,integralwith the motor and responsiveto motor currentandtemperature,providedsuch devicewill protectthe circuit conductorsand controlequipmentaswell asthemotor.(2) Fusesusedas separateoverloadprotectionof motorsshallbetimedelayfuses.11.7.3.3Numberandlocationof overloaddevices(1) Thenumberandlocationof current-responsivedevicesshallbe:(a) if fusesareused,onein eachunearthedconductor;or(b) asspecifiedin Table9.1,Section9, if devicesotherthanfusesareused.(2) Exceptby specialpermission,wherecurrent-responsivedevicesareusedfor theoverloadprotectionof 3-phasemotors,suchdevicesshallcompriseof threecurrent-responsiveelementswhichshallbe:(a) connecteddirectlyin themotorcircujtconductorsasrequiredby (1) above;or(b) fedby twoor threecurrenttransformerssoconnectedthatall 3-phaseswill beprotect~d.11.7.3.4Ratingor tripselectionof overloaddevices(1) Overloaddevicesresponsiveto motorcurrentshallberatedor selectedto trip atnotmorethanthefollowing:(a) 125%of thefull-loadcurrentratingof a motorhavinga markedservicefactorof 1.15or greater;or(b) 115%of thefull-loadcurrentratingof a motorwhichdoesnothaveamarkedservicefactoror wherethemarkedservicefactoris lessthan1.15.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 263ELECTRICAL INSTALLATION OF BUILDINGS(2) NotwithstandingtheProvisionsof (1) above,Table 11.5shallbe applicableto determinethetypeof theovercurrentdevicerequiredfor motorshavingaservicefactorof 1.15or greaterwherethefull-loadcurrentratingof themotoris listedin theTable.(3) Wherea motor overloaddeviceis so connectedthatit doesnot carrythe total currentdesignatedon the motornameplate,suchas for wye-deltastarting,the percentageof motornameplatecurrentapplyingto theselectionor settingof theoverloaddeviceshallbe clearlymarkedonthemotorstarterorshownin themotorstartermanufacturersoverloadselectiontable.11.7.3.5 Overloadprotectionnotrequired(1) Overloadprotectionshallnotberequiredfor motorscomplyingwith anyof thefollowing:(a) A manuallystartedmotorratedat 1.0hpor lessthatis continuouslyattendedwhile inoperation,whichis ona branchcircuithavingovercurrentprotectionratedor setatnotmorethan 16.0Aor on an individualbranchcircuithavingovercurrentprotectionasrequiredby Table 11.5if it maybereadilydeterminedfromthestartinglocationthatthemotoris running.(b) A motorconstructedsothatit cannotbeoverloaded.(c) A motorwhoseoperatingrequirementsaresuchthatit is impracticabletoobtainproperoverloadprotection.(d) An automaticallystartablemotorhavinga ratingof 1.0hpor lessformingpartof anassemblyequippedwith othersafetycontrolsthatprotectthemotorfrom damagedueto stalled-rotorcurrentand on which a nameplate,so locatedas to be visible afterinstallation,indicatesthatsuchprotectionfeaturesareprovided.11.7.3.6 Shuntingof overloadprotectionduringstarting(1) Overloadprotectionshallbepermittedtobeshuntedor cutoutofa circuitduringthestartingperiod,providedthatthedeviceby whichtheprotectionis shuntedor cutoutcannotbe left inthestartingpositionandthattheovercurrentdeviceis in themotorcircuitduringthestartingperiod.11.7.3.7Automaticrestartingafteroverload(]) Whereautomaticrestartingof amotoraftera shutdownonoverloadcouldcauseinjurytopersons,the overloador overheatingdevicesprotectingthe motorshall be so arrangedthatautomaticrestartingcannotoccur.264 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT11.7.3.8 Overheatingprotectionrequired(I) Each motorshallbe providedwith meansof overheatingprotectionexceptas permittedby11.7.3.10.11.7.3.9 Typesof overheatingprotection(I) Overheatingprotection,whererequiredby 11.7.3.8,shallbeprovidedby devicesintegralwiththemotorandresponsiveto bothmotorcurrentandtemperatureor to motortemperatureonly,andshallbearrangedto cutoff powerto themotoror, by spacialpermission,to activateawarningsignalwhenthetemperatureexceedsthesafelimit for themotor.(2) Motorswith inherentoverheatingprotectionacceptableunder(l) aboveshallbemarkedtoindicatethattheyarethermallyprotectedor impedanceprotected.11.7.3.10Overheatingprotectionnot required(1) Overheatingprotectionshallnotberequired:(a) wherethemotorcircuitrequiresno overloadprotectionunder11.7.3.5;or- (b) whereoverloadprotectivedevicesrequiredby 11.7.3.2adequatelyprotectthe motoragainstoverheatingdueto excesscurrentandthemotoris in a locationwhere:(i) ambienttemperaturesarenotmorethan100ehigherthanthoseat the locationoftheoverloaddevices;andOi) dustor otherconditionswill not interferewiththenormaldissipationof heatfromthemotor.11.7.4 UndervoltageProtection11.7.4.1 Undervolatgeprotectionrequiredfor motors(1) Motors shallbedisconnectedfrom thesourceof supplyin caseof low voltageby oneofthefollowing meansunlessit is evidentthatno hazardwill be incurredthroughlack of suchdisconnection:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 265ELECTRICAL INSTALLATION OF BUILDINGS(a) A motorcontroldeviceshallprovidelow-voltageprotectionwhenautomaticrestartingis liableto createa hazard.(b) The motorcontroldeviceshall providelow-voltagereleasewhen it is necessaryordesirablethatamotorstopson failureor reductionof voltageandautomaticallyrestarton returnof voltage.11.7.4.2 Undervoltageprotectiononfeedersor branchcircuits(1) The protectionspecifiedin 11.7.4.1shallbepermittedto beappliedto a feederor branchcircuit supplyinga group of motors,in which casethe individualmotorsneednot.be soprotected,providedthemeansfor manuallyresettinga low-voltageprotectivedeviceshallbewithin sightof all machinessuppliedby a feederor branchcircuit and so locatedthattheoperatorcanvisuallyassurehimselfthatsafere-energizationof thefeederor branchcircuitispossible.11.7.5 Control11.7.5.1 Controlrequired(1) Exceptas permittedby (3) below,eachmotorshallbe providedwith a motorstarterorcontrollerfor startingandstoppingit andhavingarating,in horsepower,notlessthantheratingof themotorit serv~s.(2) A motorcontrollerneednotopenthecircuitin all unearthedconductorsto amotorunlessit alsoservesasa disconnectingmeans.(3) The motor starteror controllerspecifiedin (1) aboveshall not be requiredfor motorsappliedas follows:(a) A singlephaseportablemotorratedat Y3hpor less,connectedby meansof a socketoutletandattachmentplugratednot in excessof 16.0A,230.0V.(b) A motorcontrolledby amanuallyoperatedgeneral-useswitchhavinganampereratingnot lessthan125%of thefull loadcurrentratingof themotor.(c) A two-wirepotablea.c.or d.c.motorhavinga ratingnot in excessof Y3hp,230.0Vcontrolledby a horsepowerratedsinglepolemotorswitch.266 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT11.7.5.2 Control location(1) A motor controlled manually, eitherdirectly or by a remotecontrol ofa motor starter,shallhavethe means of operation by the controller so located:(a) that safeoperationof the motor andthe machinerydriven by it is assured,or the motorand the machinery shall be guardedor enclosedsoas to preventaccidentsdueto contactof personswith live or moving parts; or(b) where compliance with (a) above is not practicablebecauseof the type, size or locationof the motor or machinery and its parts,devicesshall be provided at each point wherethe danger of accidentsexists whereby the machine or parts of the machine may bestopped in an emergency.11.7.5.3 Startershavingdifferentstartingand runningpositions(1) Manual motor startershaving different startingand running positions shall be constructedsothatthey cannot remain in the startingposition.(2) Magnetic motor startershaving different startingand running positionsshall be constructedsothatthey cannot remain in the startingposition under normal operatingconditions.11.7.5.4 Earthedcontrolcircuit(I) When power for a control circuit for a.motor controller is obtained conductively from anearthedsystem, the control circuit shall be so arrangedthat an accidental earth in the wiringfromthe controller to any remote or signal device will not:(a) start the motor; or(b) prevent the stopping of the motor by the normal operation of any control or safetydevice in the control circuit.11.7.6 DisconnectingMeans(1) Except as permittedby (2) and (3) below, separatedisconnectingmeansshall be providedfor:(a) each motor branch circuit,(b) eachmotor starteror controller, and(c) each motor.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 267ELECTRICAL INSTALLATION OF BUilDINGS(2) A singledisconnectingmeansshallbe pennittedto servemorethanoneof thefunctionsdescribedin (1) above.(3) A singledisconnectingmeansshallbe pennittedto servetwo or moremotorsandtheirassociatedstartingandcontrolequipmentgroupedon a singlebranchcircuit.(4) Disconnectingmeansor themeansfor operatingthemshallreadilybeaccessible.11.8 AIR CONDITIONING AND REFRIGERATING EQUIPMENT11.8.1 General(1) The provisionsof Section11.7for overload,overheatingandcontrolof motorsshallapplyto electricmotordrivingair conditioningandrefrigeratingequipment.11.8.2BranchCircuit(1) A roomair conditioners.hallbeconsideredasasinglemotorunit indetenniningitsbranch-circuit requirementswhenall thefollowingconditionsaremet:(a) It is cord-and-attachmentplug-connected.(b) Its ratingis notmorethan40.0A and230.0Vsinglephase.(c) Total rated-loadcurrentis shownon theroomair-conditionernameplateratherthanindividualmotorcurrents.(d) The ratingof thebranch-circuit,short-circuitandearth-faultprotectivedevicedoesnotexceedtheampacityof thebranch-circuitconductorsor theratingof thesocketoutlet,whicheveris smaller. t.(2) Thetotalmarkedratingof acord-and-attachmentplug-connectedroomairconditionershallnot exceed80%of theratingof a branchcircuitwhereno otherloadsaresupplied.(3) Thetotalmarkedratingof acord-and-attachmentplug-connectedroomairconditionershallnotexceed50%of theratingof abranchcircuitwherelightingunitsor otherappliancesarealsosupplied.268 EBCS-10 1995 ETHIOPIAN BUilDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENT11.8.3DisconnectingMeans(1) An attachmentplugandsocketoutletarepermittedto serveasdisconnectingmeansfor asingle-phaseroomair conditionerrated230.0Yor lessif:(a) themanualcontrolsontheroomairconditionerarereadilyaccessibleandlocatedwithin2.0mof thefloor; or(b) anapproved,manuallyoperableswitchis installedinareadilyaccessiblelocationwithinsightfrom theroomair conditioner.11.8.4SupplyCords(1) Wherea flexiblecordis usedto supplya roomairconditioner,thelengthof suchcordshallnotexceed2.0mfor a nominal230.0Yrating.11.9 STORAGE BATTERIES11.9.1Locationof StorageBatteries(I) Batterieswith exposedlive partsshallbekeptin a roomor anenclosureaccessibleonly toauthorizedpersonnel.11.9.2Ventilationof BatteryRoomsor Areas(I) Storage,batteryroomsor areasshallbeadequatelyventilated.(2) Storagebatteriesshallnotbesubjectedto ambienttemperaturesgreaterthan4SoC or lessthanthefreezi~gpointof theelectrolyte.11.9.3BatteryVents(1) Yentedcells shallbeequippedwith flamearresters.(2) Sealedcells shallbeequippedwith pressure-releasevents.11.9.4BatteryIn~tallation(1) Batterytrays,racksandothersurfaceson whichbatteriesaremountedshallbe:a) level,b) protectedagainstcorrosionfromthebatteryelectrolyte,ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 269ELECTRICAL INSTALLATION OF BUILDINGSc) coveredwith an insulatingmaterialhavinga dialecticstrengthof at least1500.0V,d) of sufficientstrengthto carrytheweightof thebattery,ande) designedto withstandvibrationandsway,whereappropriate.(2) Batterycellsshallbe spaceda minimumof IO.Ommapart.(3) Batterycellshavingconductivecontainersshallbe installedon non-conductivesurfaces.(4) Sealedcellsandmulti-compartmentsealedbatterieshavingconductivecontainersshallhavean insulatingsupportif a voltageis presentbetweenthecontainerandearth.(5) Cellsandmulti-compartmentventedstagebatteries,withcoverssealedtocontainersof non-conductive,heatresistantmaterial,shallnotrequireadditionalinsulatingsupport.(6) Batterieshaving a nominalvoltagegreaterthan 230.0V and with cells in rubberorcompositioncontainersshallbesectionalizedintogroupsof 230.0Vor less.11.9.5Wiring(l) The installationof wiringandequipmentin abatteryroomshallbe in accordancewiththerequirementsof a dry location.(2) The wiring betweencells and batteriesand betweenthe batteriesand otherelectricalequipmentshallbe:a) bareconductorswhichshallnotbetapped;b) openwiring;c) ajacketflexiblecord;d) mineral-insulatedcableprovidedit is adequatelyprotectedagainstcorrosionwhereitmaybe in directcontactwith acidor acidspray;or.'e) aluminium-sheathedcableprovidedthatit hasa suitablecorrosion-resistantprotection,wherenecessary.(3) Wherewiring is installedin rigid conduitor electricalmetallictubing:a) the conduitor tubingshallbe of corrosion-resistantmaterialsuitablyprotectedfromcorrosion;b) theendof theracewayshallbetightlysealedwith sealingcompound,rubbertape,orotheracceptablematerial,to resisttheentranceof electrolyteby sprayor creeping;270 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 11: INSTALLATION OF ELECTRICAL EQUIPMENTc) the conductorshall issuefrom the racewaythrougha substantialglazedinsulatingbushing;d) at least300.0mmof theconductorshallbe freefromtheracewaywhereconnectedtoa cell terminal;ande) theracewayexitshallbeatleast300.0mmabovethehighestcellterminalto reducetheelectrolytecreepageor spillageenteringtheraceway.Table 11.1 Minimumtemperaturerating for theinsulationof motorsupplyconductor[0C](Basedon ambienttemp.eratureof 30C)Insulation class ratingMotor enclosure ABFHAll except totally enclosed non-ventilated757590110Totallyenclosed non-ventilated7590110110Table11.2 Conductorsizesfor motorsfor differentservicerequirementsPercentage of nameplate current rating ofmotore--Classification of service30-andContinu15-5-mlnute minute60-ousratingminuterating ratingratingShort-timedutyOperatingvalves,raising'or lowering110120150-rolls,etc.IntermittentdutyFreight and passenger elevators,858590140tools heads, pumps, drawbridges, turntables, etc.Periodic dutyRolls, ore-and coal-handling859095140machines, etc.Varyng duty110120150200ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 271ELECTRICAL INSTALLATION OF BUILDINGSTABLE 11.3Conductorsizesin thesecondaryCircuitsof motors,....II'IIResistor dutyclassificationLight staring dutyHeavy starting dutyExtra heavystarting dutyLight intermittentdutyMedium intermittentdutyHeavy intermittentdutyContinuous dutyDutycycles5 see on 75 see off10 see on 70 see off15 see on 75 see off15 see on 45 see off15 see on 30 see of15 see on 15 see offContinuous DutyCarryingcapacityofconductorsIn percentoffull-loadsecondarycircuit354555657590110Table11.4 Ratingor settingof overcurrentdevicesfor theprotectionof motorbranchcircuits(ExceptaspermittedinTable11.5where16-Aovercurrentprotectionformotorbranchcircuitconductorsexceedsthevaluesspecifiedin here)Per centof full-loadcurrent. Maximumfuse ratingI'iType of MotorAlternatingCurrentSingle-phase all typesSquirrel-cage and synchronous:Full-voltage,resistor and reactorStaringAuto-Transformerstarting:Not more than 30.0AMore than 30.0AWound rotorDirectCurrentTlmedelay fuses175175175175150150Non-tlmedelay300300250200150150MaximumsettlngJlme-limittypecircuit breaker250250200200150150Note: (i) TheratingsoffusesfortheprotectionofmotorbranchcircuitsasgiveninTable11.5arebaseduponfuseratingsappearingin theTableabove,whichalsospecifiesthemaximumsettingsof circuitbreakersfortheprotectionof motorbranchcircuits.(H) Synchronousmotorsof thelow-torque,low-speedtype(usually450.0rpm,or lower)suchasareusedtodrivereciprocatingcompressors,pumps,etc.,andwhichstartupunloaded,donot requirea fuseratingorcircuitbreakersettingin excessof 200%of full-loadcurrent.(Hi) Fortheuseof instantaneoustrip(magneticonly)circuitinterruptersinmotorbranchcircuits,see11.7.2.5.272 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDlTable 11.5 Sizesof conductors,fuseratings,andcircuitbreakersettingsfor motoroverloadprotectionand motorcircuitovercurrentprotection(ThisTableis basedonTable11.4andaroomtemperatureof 30C).Overload protectionforOvercurrentprotectionmaximumallowable ratingof fuses and, Maximumallowablesettingof circuit breakersof the time-limitedrunningprotectionofmotor [A]Type for motorcircuits [A]Full~loadMinimum Singlephase,all typesandSquirrelcageand Synchronouscurrentallowable squirrelcageandsynchronous(AutotransformerandStar-Deltad.c.or wound rotora.c.ratingofampacityofMaximumMaximum(Fullvoltage,Resistorandmotor [A]conductorratingofsettingofReactorStarting)Starting)Type 0overloadFusesdevicesNon-timeTimedelaCircuitNon-timeTimedelaCircuitNon-timeTimeCircuitI delayy'O' delayy '0' delaydelay'0'FusesFusesbreakerfusesfusesBreakerfusesfusesbreaker11.251.1251.125151515151515151515I 22.502.252.2515151515151515151533.753.53.7515151515151515151545.004.55.0015151515151515151556.255.66.251515151515151'5151567.5077.5020151515151515151578.75 88.752515151515151515I15810.00910.00251520201515151515911.251011.253020202520151515151012.501212.503020202520201515151113.751213.753020303020202020151215.001515.004025303025202020151316.251516.254025303525302020201417.5017.517.504525303525302525201518.75. F518.75453030403030252520Table 11.5 Sizesof conductors,fuse ratings,alld circuit breaker settingsfor motor overloadprotectionand motor circuit overcurrentprotection(conte'd)(This Table is basedon Table 11.4anda room temperatureof 30C).Overload protection forOvercurrent protection maximum allowable rating of fuses andrunning protection ofMaximum allowable setting of circuit breakers of the time-limitedmotor [A]Type for motor circuits [A])Full-loadMinimum Single phase. all types andSquirrel cage and Synchronouscurrentallowable squirrel cage and synchronousMaximumMaximum(Full voltage, Resistor and(Autotransformer and Star-Deltad.c. or wound rotor a.c.rating ofampacityofStarting)motor [A]conductorrating ofsetting ofReactor Starting)Type 0overloadFusesdevicesNon-timeTimedelaCircuitNon-timeTimedelaCircuitNon-timeTimeCircuitdelayy'O'breakerdelayy '0'Breakerdelaydelay '0'breakerFusesFusesIfusesfuses fusesfuses1620.0017.520.005030404030302525I201721.252021.256030404530303030301822.502022.5060354045353030303019I23.75 2023.7560354050354030303020I25.002525.006035505035403030302227.52527.56040I506040403535302430.03030.08045606045404040302632.53032.58050607050504040I402835.03535.09050707050504545403037.53537.59060707060604545403240.04040.010060707060605050403442.54042.511060707060606060503645.04545.0110701008070706060503847.54547.512570..100 8070706060504050.05050.012570100807070606060Table 11.5Sizesof conductors,fuseratings,andcircuitbreakersettingsfor motoroverloadprotectionandmotorcircuitovercurrentprotection(conte'd)(This Table is basedon Table 11.4anda room temperatureof 30C).OverloadprotectionforOvercurrentprotectionmaximumallowable ratingof fuses andrunningprotectionofMaximumallowablesettingof circuit breakersof the time-limitedmotor [A]Type for motorcircuits [A]Full-loadMinimum Singlephase,all typesandSquirrelcageand Synchronouscurrentallowable squirrelcageandsynchronousratingofampacityofMaximumMaximum(Fullvoltage,Resistorand(AutotransformerandStar-Deltad.c. or wound rotora.c.motor [A]conductorratingofsettingofReactorStarting)Starting)Type DoverloadFusesdevicesNon-timeTimedelaCircuitNon-timeTimedelaCircuitNon-timeTimeCircuitdelayy'D'breakerdelayy 'D'Breakerdelaydelay'D'breakerFusesFuses fusesfuses fusesfuses4252.55052.5125801009080707070604455.05055.01258010090901007070604657.55057.515090100100901007070604860.06060.015090100100901008080705062.56062.5150901251-00901008080705265.06065.01751001251101001008080705467.56067.51751001251101001009090705670.07070.01751001251251001009090705872.57072.517511012512511010090901006075.07075.020011015012511010090901006277.57077.52001101501251101251001001006480.07080.02001251501501251251001001006682.58082.52001251501501251251001001006885.08085.02251251501501251251101101007087.58087.52251251751501251251101101007290.08090.02251501751501501251101101007492.59092.52251501751501501251251251007695.09095.0250150175175150150125125100 .7897.59097.5250150'17517515015012512510080100.090100.0250150200175150150125125100Table 11.5 Sizesof conductors,fuseratings,andcircuitbreakersettingsfor motoroverloadprotectionandmotorcircuitovercurrentprotection(conte'd)(This Table is basedon Table 11.4anda roomtemperatureof 30C).Overload protection forOvercurrent protection maximum allowable rating of fuses andrunning protection ofMaximum allowable setting of circuit breakers of the time-limitedmotor [A]Type for motor circuits [A]Full-loadMinimum Single phase, all types andSquirrel cage and Synchronouscurrentallowable squirrel cage and synchronousrating ofampacltyofMaximumMaximum(Full voltage, Resistor and(Autotransformer and Star-Deltad.c. or wound rotor a.c.motor [A]conductorrating ofsetting ofReactor Starting)Starting)Type DoverloadFusesdevicesNon-timeTimedelaCircuitNon-timeTimedelaCircuitNon-timeTimeCircuitdelayy'D'breakerdelayy 'D'Breakerdelaydelay'D'breakerFusesFuses fusesfuses fusesfuses82102.590102.525015020017515015012512512584105.0100105.025015020017515015015015012586107.5100107.530017520017517515015015012588110.0100110.030017520020017517515015012590112.5100112.530017522520017517515015012592115.0110115.030017522520017517515015012594117.5110117.530017522520017517515015012596120.0110120.030017522520017517515015012598122.5110122.5300175225200175175150150125100125.0110125.0300175225200175175150150150105131.5125131.5350200250225200200175175150110137.5125137.5350200250225200200175175150115144.0125144.0350225250250225225175175150120150.0125150.0400225250250225225200200175125156.5150156.5400225250250225250200200175130162.5150162.5400250300300250250200200175,135 169.0150169.0450250300300250250225225200140175.0150175.0450250350300250250225225200145181.5175181.5450300~50300300250225225200150187.5175187.5450300350300300300225225225Table 11.5 Sizesof conductors,fuseratings,andcircuitbreakersettingsfor motoroverloadprotectionandmotorcircuitovercurrentprotection(conte'd)(ThisTableis basedonTable11.4anda roomtemperatureof 30C).Overlo::.ldprotectionforOvercurrentprotectionmaximumallowable ratingof fuses andrunningprotectionofMaximumallowablesetting of circuit breakersof the time-limitedmotor [A]Type for motorcircuits [A]Full-loadMinimum Singlephase,all typesandSquirrelcageand Synchronouscurrentallowable squirrelcageandsynchronousratingofampacltyofMaximumMaximum(Fullvoltage.Resistorand(AutotransformerandStar-Deltad.c. or wound rotora.c.motor [A]conductorratingofsettingofReactorStarting)Starting)Type DoverloadFusesdevicesNon-timelimedelaCircuitNon-timelimedelaCircuitNon-timelimeCircuitdelayy'D'breakerdelayy 'D'Breakerdelaydelay'D'breakerF!JsesFuses fusesfuses fusesfuses155194175194500300350350300300250250225160200175200500300400350300300250250225165206200206500300400350300300250250225170213200213500300400350300300300300250175219200219600350400350350350300300250180225200225600350400400350350300300250185231200231600350400400350350300300250190238225238600350400400350350300300250195244225244600350400400350350300300250200250225250600350500400350400300300300210263250263-400500450400400350350300220275250275-400500450400400350350300230288250288-450500500450400350350300240300250300-450600500450400400400350250313300313-450600500450500400400350Table 11.5 Sizesof conductors,fuseratings,andcircuitbreakersettingsfor motoroverloadprotectionandmotorcircuitovercurrentprotection(conte'd)(This Table is basedon Table 11.4anda room temperatureof 30C).OverloadprotectionforOvercurrentprotectionmaximumallowableratingof fuses andrunningprotectionofMaximumallowablesetting of circuit breakersof the time-limitedmotor [A]Type for motorcircuits [A]Full-loadMinimum Singlephas~,alltypesandSquirrelcageand Synchronouscurrentallowable squirrelcage andsynchronousratingofampacltyofMaximumMaximum(Fullvoltage,Resistorand(AutotransformerandStar-Deltad.c. or wound rotora.c.motor [A]conductorratingofsettingofReactorStarting)Starting)Tvpe DoverloadIFusesdevicesNon-timeTlmedelaCircuitNon-timeTlmedelaCircuitNon-timeTimeCircuitdelayy'O'breakerdelayy '0.Breakerdelaydelay.'0'breakerFusesFuses fusesfuses fusesfuses260325300325-500600600500500400400350270336300336-500600600500500450450~OO260'350300350-500600600500500450450'400290363350363-600600600600500450450400300375'350375-600600600600600450450400320400350400----~-500500400340425400425------600600500360450400450------600600500360475450475------600600500400500450500------6006006004205~5500525---------440550500550---------460575500575---------460600500600--'-------500625600625---------SECTION 12HAZARDOUS LOCATIONS12.1 SCOPE(1) This Section appliesto hazardouslocationsin which electricalequipmentand wiringaresubjectto the conditionsclassifiedasfollows:(a) ClassI locationsin which flammablegasesor vapoursareor maybe presentinthe air in quantitiessufficientto produceexplosiveor ignitiblemixtures;(b) ClassII locationwhicharehazardousbecauseofthe presenceof combustibleorelectr.icallyconductivedusts;and(c) ClassIII locationswhicharehazardousbecauseof thepresenceof easilyignitiblefibres or flyings,but in which such fibres or flyings are not likely to be insuspensionin the air in quantitiessufficientto produceignitiblemixtures.12.2 NORMATIVE REFERENCE(l) Thefollowingreferencecontainsprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.(a) C22.1:1990 CanadianElectricalCode, Part 1,SafetyStandardfor ElectricalInstallations,SixteenthEdition.12.3 CLASSIFICATION12.3.1 Division of Class I Locations(1) ClassI locationsshallbe dividedinto two divisionsasfollows:(a) Division 1,comprisingClassI locationsin which:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 279ELECTRICAL INSTALLATION OF BUILDINGSi) hazardousconcentrationof flammablegasesorvapoursmayexistcontinuously,intermittently,or periodicallyundernormaloperatingconditions;ii) hazardousconcentrationsof flammablegasesor vapoursmayexistfrequentlybecauseof repairor maintenanceoperationorbecauseof leakage;oriii) equipmentis operatedor processesare carriedon, of sucha naturethatbreakdownor faultyoperationthereofcouldresultin thereleaseof hazardousconcentrationsof flammablegasesor vapoursand simultaneousfailureofelectricalequipment.(b) Division2,comprisingClassI locationsinwhich:(i) flammablevolatileliquids,flammablegasesorvapoursarehandled,processed,or used,but in whichthe liquids,gases,or vapoursarenormallyconfinedwithinclosedcontainersorclosedsystemsfromwhichtheycanescapeonlyasaresultof accidentalraptureorbreakdownofthecontainersor systemsor theabnormaloperationof the equipmentby whichthe liquidsor gasesarehandled,processed,or used;or(ii) hazardousconcentrationof gassesor vapoursare normallypreventedbypositivemechanicalventilation,bu.twhichmaybecomehazardousasther~sultof failureor abnormaloperationof theventilatingequipment;or(iii) the IQcationis adjacentto a ClassI, Division1 location,from whichahazardous~ncentrationof gas~esorvapourscouldbecommunicated,unlesssuchcommunicationis preventedby adequatepositive-pressure'ventilationfroma sourceof cleanair,andeffectivesafeguardsagainstventilationfailureareprovided.12~3.2Divisionof ClassII Locations(1) ClassIIlocationsshallbedividedintotwodivisionsasfollows:a) Division1comprisingClassIIlocationsinwhich:i) combustibledustis or maybe ih suspensionin aircontinuously,intermittently,or periodicallyundernormaloeperatingconditionsin quantitiessufficienttoproduceexplosiveor ignitiblemixtures;ii)'.thenormalorabnormaloperationorthefailureofequipmentorapparatusmightcauseexplosiveor ignitiblemixturestobeproducedin,or indangerousproximityto,'electricalequipmentor apparatus;or280 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 12: HAZARDOUS LOCATIONSiii dustshavingthepropertyof conductingelectricitymaybepresent.b) Division2,comprisingClass.IIlocationsinwhichcombustiBledustsarenotnormallyin suspensionin air or likelyto be throwninto suspensionby the normalorabnormaloperationor thefailureof equipmentorapparatusin quantitiessufficientto produceexplosiveor ignitiblemixtures,butinwhich:i) depositsor accumulationsof dustmaybe sufficientto interferewith thesafedissipationof heatfromelectricalequipmentor apparatus;orii) depositsor accumulationsof duston, in or nearelectricalequipmentmaybeignitedbyarcs,sparks,orburningmaterialfromtheelectricalequipment.12.3.3Divisionof ClassIII Locations(1) ClassIII locationsshallbedividedintotwodivisionsasfollows:a) Division 1, comprisingClassIII locationsin which readilyignitiblefibr~sormaterialsproducingcombustibleflyingsarehandled,manufactured,or used.b).Division2,comprisingClassIII locationsinwhichreadilyignitiblefibresotherfhanthosein processof maI}.ufacturearestoredor handled.12.4 GENERAL REQUIREMENTS12.4.1ElectricalEquipment(1) WhereelectricalequipmentisrequiredbythisSectionto beapprovedfor theclassoflocation,it shallalsobeapprovedfor thespecificgas,vapour,or dustthatwill bepresent.(2) Suchapprovalin (1) maybeindicatedbyoneor moreof thefollowingatmospheric-gI:oupdesignationswhichhavebeenestablishedfor thepurposeof testingandapproval:a) GroupA, comprisingatmospherescontainingacetylene;b) GroupB, comprisingatmospherescontainingbutadiene,ethyleneoxide,hydrogen(orgassesorvapoursequivalentin hazardtohydrogen,suchasmanufacturedgas),or propyleneoxide;ETHIOPIAN BUILDING CODE SifANDARD EBCS-10 1995 281ELECTRICAL INSTALLATION OF BUILDINGSc) Group C, comprisingatmospherescontainingacetaldehyde,cyclopropane,dlethyl.ether,ethylene,or unsymmetricaldimenthylhydrazine(UDMH), or othergasesorvapoursof equivalenthazard;d) Group D, comprisingatmospherescontainingacetone,acrylonitrile,alcohol,ammonia,benzine,benzol,ethylenedichloride,gasoline,hexane,isoprene,lacquersolventvapours,naphtha,naturalgas,propane,propylenestyrene,vinylacetate,vinylchloride,xylenes,or othergasesorvapoursor equivalenthazard;e) Group E, comprisingatmospherescontainingmetaldust,includingaluminum,magnesium,andtheircommercialalloys,andothermetalsof similarlyhazardouscharacteristics;f) GroupF, comprisingatmospherescontainingcarbonblack,coalor cokedust;g) GroupG, comprisingatmospherescontainingflour,starchorgraindust,andotherdustsof similarlyhazardouscharacteristics.12.4.2Marking(1) Electrical,equipmentapprovedfor use in hazardouslocationsshallbe markedtoindicatetheclassandfor ClassesI andII locationsthegroup,or thespecificgas,vapouror dustforwhichtheequipmenthasbeenapproved.(2) Electricalequipmentapprovedfor usein ClassI hazardouslocationsmaybetJ1arkedwith:a) themaximumexternaltemperature,orb) one of the followingtemperaturecodesin Table12.1to indicatethe maximumexternaltemperature:,Table12.1Temperaturecodesto indicatethemaximumexternaltemperatureTemperature Max. externalTemperatureMax. externalcodetemperature [0C]oodetemperature [0C]T1450T3A 180T2300T38 165T2A280T3C 160T28260T4 135T2C230T4A 120T20215T5 100T3200T6 85282 EBCS-10 1995.ETHIOPIAN BUILDING CODE STANDARDSECTION 1 H RDOUS LOCATIONS(3) If nomaximumexternaltemperaturemarkingisshownonClassI equipmentapprovedfor theclassandgroup,the equipment,if of theheat-producingtype(whichexcludesjunctionboxes,conduitfittings,etc),shallbeconsideredashavingthefollowingmaximumexternaltemperature:GroupA - 28O'CGroupB - 28O'CGroupC - 160'CGroupD - 215C(4) Equipmentapprovedfor ClassI, Division2 onlyshallbesomarked.(5) slectricalequipmentapprovedfor operationatambienttemperaturesexceeding40'Cshall,in additionto themarkingspecifiedin 12.4.2bemarkedwiththemaximumambienttemperatureforwhichtheequipmentisapproved,andthemaximumexternaltemperatureof theequipmentasreferredto in (2)and(3)above.12.4.3Non-EssentialElectricalEquipment(1) No electricalequipmentshallbeusedin a hazardouslocationunlessit is essentialtotheprocessesbeingcarriedontherein.(2) Serviceequipment,panelboards,switchboards,andsimilarelectricalequipmentshall,'wherepracticable,be locatedin roomsor sectionsof thebuildingin whichhazardousconditionsdonotexist.12.4.4EquipmentRooms(1) Wherewalls,partitions,floorsor ceilingsareusedto form hazard-freeroomsorsections,theyshallbe:a) of substantialconstruction;b) builtof or linedwithnoncombustiblematerial;andc) suchasto ensurethattheroo~ or sectionwill remainfreefromhazards.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 283ELECTRICAL INSTALLATION OF BUILDINGS(2) Where a non-hazardouslocationwithina buildingcommunicateSwith a ClassI,Division2 location,a ClassII location,or a Classilllocation,the locationsshallbeseparatedbyclose-fittings,self-closing,.approvedfiredoors.12.4.5CableTrays(1) Cabletraysshallnotbeusedto supportcablesin hazardouslocationsexceptwhere:a) the typeof cableis approvediil Clausesof thisSectionfor usein theparticularhazardouslocation;andb) therecanbenohazardousaccumulationof combustibleprocessdustor fibrein oruponthecable;thecabletrayor thesupports.12.5 CLASS I WCATION12.5.1 Installationsin ClassI, Divisiop1Locations12.5.1.1 Transformersandcapacitors(1) Transformersandelectricalcapacitorswhichcontainacombustibleliquidthatwillburnshallbe installedin electricalequipmentvaultsin accordancewithapplicableClausesofSection11.12.5.1.2Meiers,instrumentsandrelays(1) Wherepracticable,meters,instrumentsand relays,includingkilowatt-hourmeters,instrumenttransformersand resistors,rectifiersand thermionictubesshallbe locatedoutsidethehazardouslocations.(2) Whereit is notpracticableto installmeters,instruments,andrelaysoutsideClassI,Division1 locations,theyshallbeapprovedfor ClassI locations.12.5.1.3 Switches,motorcontrollers,circuitbreakersandfuses(1' Switches,motorcontrollers,circuitbreakersandfuses,includingpushbuttons,relays,andsimilardevicesshallbeprovidedwithenclosures;theenclosurein eachcase,togetherwith theenclosedapparatus,shallbeapprovedasa completeassemblyfor usein ClassIlocations.284 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 12: HAZARDOUS LOCATIONS12.5.1.4Motorsandgenerators(1) Motors,generatorsandotherrotatingelectricalmachinesshallbeapprovedfor ClassI locations.12.5.1.5 Wiringmethods(1) The wiringmethodshallbe threadedrigid-metalconduitor cablesapprovedforhazardouslocationswith associatedcableglandsapprovedfor theparticularhazardouslocation.(2) All boxes,fittings,andjointsshallbe threadedfor connectionto conduitor cableglands,andshallbeexplosion-proofwithboxesandfittingsapprovedfor ClassI locations.(3) Threadedjointsshallhaveat leastfivefull threadsfullyengagedandrunningthreadsshallnotbe'used.(4) Cablesshallbeinstalledandsupportedin a mannerto avoidtensilestressatthecable glands.(5) Whereit is necessaryto useflexibleconnectionsatmotorterminalsandsimilarplaces,flexiblefittingsof theexplosion-prooftypeandapprovedfor thelocationshallbeused.(6) Sealsshallbeprovidedin conduitor cablesystemsto preventthepassageof gases,vapours,or flamesfrom oneportionof theelectricalinstallationto anotherthroughthesystem.12.5.1.6Lightingfixtures(1) Fixturesfor fixedandportablelightingshallbe approvedascompleteassembliesforClassI locationsandshallbeclearlymarkedto indicatethemaximumwattageof lampsforwhichtheyareapproved.(2) Boxes,box assembliesor fittingsusedfor the supportof lightiRgfixturesshallbeapprovedfor thepurposeandfor ClassI locations.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 285ELECTRICAL INSTALLATION OF BUILDINGS12.5.2 Installationsin ClassI, Division2 Locations12.5.2.1 Wiringmethods(1) Thewiringmethodshallbe:a) threadedmetalconduit;orb) cablesapprovedfor hazardouslocationswithassociatedcableglandsapprovedfortheparticularhazardouslocation.(2) Cableshallbe installedandsupportedin a mannerto avoidtensilestressatthecableglands.(3) Whereit is necessaryto useflexibleconnectionatmotorterminalsandsimilarplaces,flexiblemetalconduitmaybeused.(4) Boxes,fittingsandjointsneednotbeexplosion-proof.(5) Sealsshallbe providedin conduitor cablesystemsto preventthepassageo(gases,vapours,or flamesthroughthesystemfromoneportionof theelectricalinstallationtoanother.12.5.2.2 Motorsandgenerators(1) Motors,generators,andotherrotatingelectricalmachines,in whichareincorpor~tedarcingor spark-producingcomponentsor integralresistancedevices,shallbeapprovedforClassI, Division2 locationsunlessthearcingor spark-producingcomponentsor integralresistancedevicesareprovidedwithenclosuresapprovedfor ClassI locations.(2) Motors,generators,andotherrotatingelectricalmachineswhichdo not incorporatearcingor sparkproducingcomponentsor integralresistancedevicesmaybeof theopenornon-explosion-prooftype.12.5.2.3 Lightingfixtures(1) Fixedlightingshallbe:a) protectedfromphysicaldamagebyacceptableguardsor bylocation;286 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD12.6 CLASS II LOCATIONSECTION 12: HAZARDOUS LOCATIONS12.6.1 Installationsin ClassII, Division1LocationsEBCS-10 1995 287ETHIOPIAN BUILDING CODE STANDARD12.6.1.4 Wiringmethodsb) approvedascompleteassembliesforClassI, Division2 locationsandshallbeclearlymarkedto indicatethemaximumwattage,voltage,andspecifictypedesignationsof thelampsforwhichtheyareapproved.(2) Boxes,fittingsandjointsshallbe threadedfor connectionto conduitor cableglandsandboxesandfittingsshallbeapprovedfor ClassII locations.(1) The wiring methodshallbe threadedrigid metalconduitor cablesapprovedforhazardouslocationswith associatedcableglandsapprovedfor theparticularhazardouslocation.12.6.1.3Motorsandgenerators(2) Pendentfixturesshallbe suspendedby threadedrigidconduitsystemsor by otherapprovedmeans.12.6.1.2Switches,conJroUers,circuitbreakersandfuses(1) Switches,motorcontrollers,circuitbreakersandfuses,includingpushbuttons,relays,andsimilardevices,shallbeprovidedwith a dust-tightenclosureapprovedfor ClassIIlocations.(3) Startingand controlequipmentfor electric-dischargelightingequipmentshall bepr0v.idedwithenclosuresapprovedfor thelocation.(1) Transformersand electricalcapacitorswhichcontaina combustibleliquidshallbeinstalledin electricalequipmentvaultsin accordancewithapplicableClausesof Section11,.12.6.1.1 Transformersandcapacitors(1) Motors,generatorsandotherrotatingelectricalmachinesshallbeapprovedfor Classn locations.,(3) Cablesshallbeinstalledandsupportedin a mannerto avoidtensilestressatthecableglands.(4) Whereflexibleconnectionsarenecessary,theyshallbeprovidedby:a) flexibleconnectionfittingsapprovedfor thelocation;b) liquid-tightflexiblemetalconduitwithfittingsapprovedfor thelocation;orc) extra-hard-usageflexiblecordandprovidedwith cableglandsapprovedfor thelocation.(5) Whereflexibleconnectionsaresubjectto oil or corrosiveconditions,theinsulationoftheconductorsshallbeof typeapprovedfor theconditionor shallbeprotectedbymeansofa suitablesheath.(6) Wherearacewayprovidescommunicationbetweenenclosuresoneofwhichisrequiredtobedust-tightandtheothernot,theentranceof dustintothedustenclosurethroughtheracewayshallbepreventedby:a) apermanentandeffectiveseal;b) a horizontalsectionnotlessthan3.0mlongin theraceway;orc) averticalsectionof racewaynotlessthan105mlongandextendingdownwardwith.thedusttightenclosure.12.6.1.5Lightingfixtures(1) Fixturesfor fixedandportablelightingshallbeapprovedascompleteassembliesforClassIIlocationsandshallbeclearlymarkedto indicatethemaximumwattageof lampsforwhichtheyareapproved.(2) Pendentfixturesshallbe suspendedby threadedrigidconduitstemsor chainswithapprovedfittingsorbyotherapprovedmeanswhichshallnotincludea flexiblecordasthesupportingmedium,andthreadedjointsshallbeprovidedwithsetscrewsorothereffectivemeansto preventloosening.(3) Boxes,box assembliesor fittingsusedfor thesupportof lightingfIxturesshallbeapprovedfor thepurpose.288 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD12.6.2SECTION 12: HAZARDOUS LOCATIONSInstallationin ClassII, Division2 Locations12.6.2.1 Transformersandcapacitors(1) Transformersandelectricalcapacitorswhichcontaina combustibleliquid shallbeinstalledin electricalequipmentvaultsin accordancewithapplicableclausesof Sections11.12.6.2.2 Switches,controUers,circuit'breakersandfuses(1) In locationswheredustfrommagnesium,aluminum,aluminumbronzepowders,orother metalsof similar hazardouscharacteristicsmay be present,switches,motorcontrollers,circuitbreakers,andfusesshallhavedust-tightenclosuresapprovedfor suchlocations.12.6.2.3 Motorsandgenerators(1) Motors,generatorsandotherrotatingelectricalmachineryshallbe:a) approvedfor ClassII, or ClassII Division2 locations;b) ordinary,totallyenclosedpipe-ventilatedor totallyenclosedfan-cooledandsubjectto thefollowing:i) beequippedwithintegraloverheatingprotectionin accordancewith11.7.3.8ii) if drainholesor otheropeningsareprovidedtheyshallbeclosedwiththreadedplugs.12.6.2.4 Wiringmethods(1) Thewiringmethodshallbe:a) threadedmetalconduit;orb) cablesapprovedfor hazardouslocationswithassociatedcableglandsapprovedfortheparticularhazardouslocation.(2) Cablesshailbeinstalledandsupportedin a mannerto avoidtensilestressatthecableglands.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 289ELECTRICAL INSTALLATION OF BUILDINGS12.6.2.5 Lightingfixtures(1) Fixedlightingshall:a) beprotectedfromphysicaldamagebyacceptableguardsor bylocation;b) provideenclosuresfor lampandlampholderswhichshallbedesignedto minimizethedepositof duston lampsandtopreventtheescapeof sparks,burningmaterial,or hotmetal;c) beclearlymarkedto indicatethemaximumwattageof lampsforwhichtheymaybeusedwithoutexceedinga maximumexposedsurfacetemperatureof 165Cundernormalconditionsor use.(2) Pendentfixturesshallbe suspendedby threadedrigidconduitstemsor chainswithappro.vedfittings,or byotherapprovedmeans,whichshallnotincludeflexiblecordasthesupportingmedium.(3) Boxes,box assembliesor fittingsusedfor thesupportof lightingfixturesshallbeapprovedfor thatpurpose.(4) Startingandcontrolequipmentformercury-vapourandfluorescentlampsshallconformto therequirmentof 12.6.2.2.12.7 CLASS III LOCATIONS12.7.1Installationsin ClassIII, Division1Locations12.7.1.1 Transformersandcapacitors(1) Transformersandcapacitorsshallconformto therequirementof 12.6.2.112.7.1.2 Switches,cntrollers,circuitbeakersandfuses(1) Switches,motorcontrollers,circuitbreakersandfuses,includingpushbuttons,relay~andsimilardevices,shallbeprovidedwithtightenclosuresdesignedto minimizeentranceof fibresandflyings,andwhichshall:a) beequippedwithtelescopingor closefittingcovers,or withothereffectivemeansto preventescapeof sparksor burningmaterial;and290 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 12: HAZARDOUS LOCATIONSb) haveno openings,suchas holesfor attachmentscrews,throughwhich,afterinstallation,sparksor burningmaterialmightescape,or throughwhichexterioraccumulationsof fibresor flyingsor adjacentcombustiblematerialmightbeignited.12.7.1.3Motorsandgenerators(1)Exceptasprovidedin(2)below,motors,generatorsandotherrotatingelectricalmachineryshallbe:a) totallyenclosednon-ventilated,b) totallyenclosedpipe-ventilated,c) totallyenclosedfan-cooled.(2)Whereonlymoderateaccumulationsof lintandflyingsarelikelytocollectonor inthevicinityof a rotatingelectricalmachineandthemachineis readilyaccessiblefor routinecleaningandmaintenance,theremaybeinstalledin thelocation:a) standardopen-typemachineswithoutslidingcontacts,centrifugal,orothertypesofswitchingmechanism,includingmotoroverloaddevices;b) standardopen-typemachineswhich havecontacts,switchingmechanisms,orresistancedevicesenclosedwithin tight housingswithoutventilatingor otheropemngs;orc) self-cleaningtextilemotorsof thesquirrel-cagetype.(3)Motors,generatorsandotherrotatingelectricalmachineryof thepartiallyenclosedorsplash-prooftypeshallnotbeinstalledin ClassIII locations.12.7.1.4Wiringmethods(1)The wiringmethodshallbe threadedrigid metalconduitor cablesapprovedforhazardouslocationswith associatedcableglandsapprovedfor theparticularhazardouslocation.(2)Boxesandfittingsinwhichtaps,jointsor terminalconnectionsaremadeshall:a) be providedwith telescopingor closefittingcovers,or othereffectivemeanstopreventtheescapeof sparksor burningmaterial;andETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 291ELECTRICAL INSTALLATION OF BUILDINGSb) haveno openings,suchas holesfor attachmentscrews,throughwhich afterinstallation,sparksor burningmaterialmightescape,or throughwhichadjacentcombustiblematerialmightbeignited.(3) Cablesshallbeinstalledandsupportedin amannerto avoidtensilestressatthecableglands.(4) Whereit is necessaryto useflexibleconnections,theprovisionsof 12.6.1.4(4)and12.6.1.4(5)shallapply.12.7.1.5 Lightingfixtures(1) Fixedlightingshall:a) provideenclosures,for lampsandlampholders,whichshallbedesignedtominimizeentranceof fibresandflyingobjectsandto preventtheescapeof sparks,burningmaterial,or hotmetal;b) be clearlymarkedto indicatethe maximumwattagelampwhichmaybe usedwithoutexceedingamaximumexposedsurfacetemperatureof 165CunderRormalconditionsof use.(2) Lightingfixtureswhichmay~eexposedto phystcaldamageshallbe protectedbyasuitableguard.(3) Pendentfixturesshallcomplywiththerequirmentsof 12.6.2.5(2).(4) Boxes,box assembliesor fittingsusedfor the supportof lightingfixturesshallbeapprovedfor thatpurpose.12.7.1.6 Storage-batterychargingequipment(1) Storagebatterychargingequipmentshallbelocatedin a separateroombuiltor linedwithsubstantialnoncombustiblematerialssoconstructedasto adequatelyexcludeflyingsor lint,andshallbewellventilated.292 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 12: HAZARDOUS LOCATIONS12.7.2 Installationsin ClassIII, Division2Locations12.7.2.1 Transformersandcapacitors(1) Transformersandcapacitorsshallconformto therequirementof 12.6.2.1.12.7.2.2 Wiringmethod(1) Thewiringmethodin ClassIII, Division2 locationsshallconformto 12.7.1.4exceptthat in sections,compartmentsor areasused solelyfor storageand containingnomachinery,openwiringon insulators,in accordancewithapplicableClausesof Section8,maybeused,providedthat,whereconductorsareinstalledelsewhereotherthanin roofspacesandremotefromphysicaldamage,theyshallbeprotectedbyrunningboardnotlessthan19.0mmthickor otheracceptablemeans.12.7.2.3 Switches,controllers,circuitbreaker.tandfuses(1) Switches,motorcontrollers,circuitbreakers,andfusesshallconformtotherequirementof 12.7.1:2.12.7.2.4 Motorsandgenerators(1) Motors,generators,andotherrotatingelectricalmachineryshallbe:.a) totallyenclosednon-ventilated;b) totallyenclosedpipe-ventilated;orc) totallyenclosedfan-cooled.(2) Motors,generatorsor otherrotatingelectricalmachineryof thepartiallyenclosedor splashprooftypeshallnotbeiI)Stalledin ClassIII locations.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 293SECTION 13FlAMMABLE UQUID DISPENSING ANDSERVICE STATIONS, GARAGES,BULK STORAGE PlANTS, FINISIllNGPROCESSES AND AIRCRAFf HANGARS13.1 SCOPE(1) This Sectionappliesto electricalapparatusand wiring installedin the followingfacilities:a) Gasolinedispensingandservicestations,andotherlocationswheregasolineorothersimilarvolatileflammableliquidsaredispensedor transferredto fueltanksof self-propelledvehicles.b) Commercialgarages,repairhousesandstoragewhereserviceandrepairoperationsof vehiclesof thetypedescribedin (a) abovearecarriedout andin whichmorethanthreesuchvehiclesare,or maybe,storedatanyonetime.c) Residentialstoragegaragesin whichnot morethanthreevehiclesof the typedescribedin (a) aboveare,or maybe,stored,butwhichwill notnormallybeusedfor serviceor repairoperations.d) Bulk storageplantswheregasolineor othersimilarvolatileflammableliquidsarestoredin tankshavingan aggregatecapacityof one-car-Ioador more,andfromwhichsuchproductsaredistributed(usuallybytanktruck).e) Finishingprocesseswherepaints,lacquersorotherflammablefinishesareregularlyor frequentlyappliedbyspraying,dipping,brushingor byothermeans,andwherevolatileflammablesolventsor thinnersareusedor wherereadilyignitibledepositsor residuesfromsuchpaints,lacquers,or finishesmayoccur.294 EBCS-10 1995 ETHIOPIAN BUILDING CODE STAN'DARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIESt) Aircrafthangarsusedfor storageor servicingof aircraftinwhichgasolinejet fuels,or othervolatileflammableliquids,or flammablegases,areused;but shallnotincludethoselocationsusedexclusivelyfor aircraftsthathavenevercontainedsuchliquidsor gases,orwhichhavebeendrainedandproperlypurged.13.2 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationof Buildings.(a) C22.1:1990 CanadianElectricalCode,Part 1 SafetyStandardforElectricalInstallations,SixteenthEdition.13.3.1HazardousAreas13.3 GASOLINE DISPENSING AND SERVICE STATIONS(2) The spacewithina nozzlebootof a dispensershallbe consideredto be a ClassIDivision1 location.NationalElectricalCodeHandbook,Basedon the1981(NEC), SeventeenthEdition.(b) NEC Handbook:1981(1) Thespacewithinad~penserenclosureupto1.2mverticallyaboveitsbaseincludingthespacebelowthe dispenserwhichmaycontainelectricalwiringandequipmentshallbeensideredto beClassI, Division1location.(3) The spacewithin 450.0mmhorizontallyfrom the Division1 locationwithin thedispenserenclosureasspecifiedin (1)aooveshaUbeconsideredto bea ClassI, Division1location.(4) In an outsidelocation,anyareabeyondthe ClassI, Division1 areawithin6.0mhorizontallyfromtheexteriorenclosureof anydispensershallbeconsidereda ClassI,Division2 location,whichwill extendto a level4~O.Ommabovedrivewayor groundlevel.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 295ELECTRICAL INSTALLATION OF BUILDINGS(5) In anoutsidelocation,anyareabeyondtheClassI, Division1locationandwithin3.0mhorizontallyfromanytankfillpipeshallbeconsidereda ClassI, Division2 'locationwhichshallextendupwardto a level450.0mmabovedrivewayorgroundlevel.(6) Electricalwiringandequipment,anyportionof whichis belowthesurfaceof areasdefinedasClassI, Division1orDivision2 in (1),(3),(4)or (5)aboveshallbeconsideredto be within ClassI, Division1 locationwhichshallextendat leastto the point ofemergenceabovegrade.(7) Areaswithinthevicinityof tankventpipesshallbeclassifiedasfollows:a) The sphericalvolumewithina 900.0mmradiusfrompointof dischargeof anytankventpipeshallbeconsidereda ClassI, Division1 locationandthevolumebetweenthe900.0mmto 1.5mradiusfrompointof dischargeof aventshallbeconsidereda ClassI, Division2 location.b) For anyventthatdoesnotdischargeupward,thecylindricalvolumebelowboththeDivision1 andDivision2 locationsextendingto thegroundshallbeconsideredasClassI, Division2 location.c) The hazardousareashallnotbe.consideredto extendbeyondanunpiercedwall.(8) Areaswithinlubricationroomsshallbeclassifiedasfollows:a) The areawithinanypit or spacebelowgradeor floor levelshallbeconsideredaClassI, Division1 locationunlessthepit or spaceis beyondthehazardousareasspecifiedin (4),(5),(6),(7)aboveinwhichcasethepitor spaceshallbeconsidereda ClassI Division2 location.b) Theareawithintheentirelubricationroomupto50.0mmabovethefloororgrade,whicheveris thehigher,andtheareawithin900.0mmmeasuredin anydirectionfrom thedispensingpointof a hand-operatedunitdispensingvolatileflammableliquidsshallbeconsidereda ClassI, Division2 location.13.3.2WiringandEquipmentwithinHazardousAreas(1) Electricalwiringandequipmentwithinthehazardousareasdefinedin Clause13.3.1shallconformto therequirementsof Section12.296 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIES(2) Wheredispensersaresuppliedbyrigidmetalconduit,flexiblefittingsof theexplosion-prooftypeapprovedforthelocationshallbeusedbetweentheconduitandthejunctionboxofthedispenserinadditiontoanysealingfittingsandunionsthatmayberequiredpursuanttotheprovisionsof Section12.(3) Eachcircuitleadingtoor throughadispensingpumpshallbeprovidedwithaswitchingmeanswhichwill disconnectsimultaneouslyfrom the sourceof supplyall unearthedconductorsof thecircuit.(4)All non-current-carryingmetalpartsof dispensingpumps,metalracewaysandotherelectricalequipmentshallbebondedtoearthin accordancewithSection7of thisCode.13.3.3WiringandEquipmentaboveHazardousAreas(1)Wiring and equipmentabovehazardousareasshall meetthe requirementsandprovisionsof Clauses13.4.3and13.4.4of thisSection.13.4 COMMERCIAL GARAGES,REPAIRS AND STORAGE13.4.1HazardousAreas(1)For eachfloorator abovegrade,theentireareaupto alevel50.0mmabovethefloorshallbeconsideredto bea ClassI, Division2 location.(2)For eachfloorbelowgrade,theentireareaupto a level50.0mmabovethebottomofoutsidedoorsor otheropeningswhichareator abovegradelevelshallbeconsideredtobea ClassI, Division2 locationexceptthat,whereadequatemechanicalventilationisprovided,thehazardouslocationshallextendupto alevelof only50.0mmaboveeachsuchfloor.(3)Anypit or depressionbelowfloor levelshallbeconsideredto bea ClassI, Division2locationwhichshallextendup to thefloorlevel.(4)Adjacentareasin whichhazardousvapoursarenot likelyto be releasedsuchasstockrooms,switchboardrooms,andothersimilarlocationshavingfloorselevatedat least50.0mmabovetheadjacentgaragefloor,or separatedtherefrombytightcurbsorpartitionsatleast50.0mmhigh,shallnotbeclassifiedashazardous.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 297ELECTRICAL INSTALLATION OF BUILDINGS13.4.2WiringandEquipm~ntin HazardousAreas(1) Within hazardousareasas definedin Clause13.4.1,wiring and equipmentshallconformto therequirementsof applicableClausesof Section12.13.4.3WiringaboveHazardousAreas(1) All fixedwiringabovehazardousareasshallbe carriedout in accordancewith theprovisionsof Section8 andsuitablefor thetypeof buildingandoccupancy.(2) For pendants,flexiblecordof thehard-usagetypeshallbeemployed.(3) For connectionof portablelamps,portablemotors,or otherportableutilizationequipment,flexiblecordof thehard-usagetypeshallbeused.13.4.4EquipmentaboveHazardousAreas(1) Fixedequipmentwhichis lessthan3.6mabovethefloorlevelandwhichmayproducearcs,sparks,or partiClesof hotmetalsuchascutouts,switches,chargingpanels,generators,motorsorotherequipment(excludingsocketoutlets,lampsandlampholders)havingmake-and-breakor slidingcontacts,shallbeof thetotallyenclosedtypeor so constructedastopreventescapeof sparksor hotmetalparticles.(2) Lampsandlampholdersforfixedlightingandthatarelocatedoverlanesthroughwhichvehiclesarecommonlydrivenorwhichmayotherwisebeexposedtophysicaldamageshallbe locatednot lessthan3.6mabovefloor levelunlessof totallyenclosedtypeor soconstructedasto preventescapeof sparksor hotmetalparticles.13.5 RESIDENTIAL STORAGEGARAGES13.5.1Non-HazardousLocation(1) Wherethelowestflooris ator aboveadjacentgradeordrivewaylevel,andwherethereis at leastoneoutsidedoorator belowfloorlevel,thegarageareashallnotbeclassifiedasa hazardouslocation.298 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIES13.5.2HazardousLocation(1) Wherethelowestfloor is belowadjacentgradeor drivewaylevel,thefollowingshallapply:a) The entireareaof thegarageor of anyenclosedspacewhichincludesthegarageshallbe classifiedasa ClassI, Division2 locationandwill extendup to a level50.0mmabovethegaragefloor.b) Adjacentareasin whichhazardousvapoursor gasesarenotlikelyto bereleased,andhavingfloorselevatedat least50.0mmabovethegaragefloor,or separatedtherefrombytightcurbsor partitionsatleast50.0mmhighshallnotbeclassifiedashazardous.13.5.3Wiring(1) Wiringabovethehazardouslocationsshallconformto theprovisionsof Section8.(2) Wiringin thehazardouslocationshallconformto theprovisionsof Section12.13.6 BULK STORAGE PLANTS13.6.1HazardousAreas(1) Neas containingpumps,bleeders,withdrawalfittings,metresandsimilardeviceswliicharelocatedin pipelineshandlingflammableliquidsunderpressureshallbeclassifiedandcomplywiththefollowing:a) VentilatedindoorareasshallbeconsideredasClassI, Division2 locationswithina 15mdistanceextendingin alldirectionsfromtheexteriorsurfaceof suchdevicesaswellas7.5mhorizontallyfromanysurfaceof thesedevicesandextendingupwardsto 900.0mmaboveflooror gradelevel,providedthat:i) designof theventilationsystemstakesintoaccounttherelativelyhighrelativedensityof thevapours;ii) whereopeningsareusedin outsidewalls,theyareof adequatesizeandlocatedat floorlevelunobstructedexceptbylouvresor coarsescreens;andETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 299ELECTRICAL INSTALLATION OF BUILDINGSiii) wherenaturalventilationis inadequate,mechanicalventilationisprovided.b) Indoor areasnot ventilatedin accordancewith (a) aboveshallbe consideredClassI, Division1 locationswithina 15mdistanceextendingin alldirectionsfromtheexteriorsurfaceof suchdevicesaswellas7.5mhorizontallyfromanysurfaceofthedeviceandextendingupward900.0mmabovefloororgradelevel.c) OutdoorareashallbeconsideredasClassI,_Division2 locationswithina 900.0mmdistanceextendingin alldirectionsfromtheexteriorsurfaceof suchdevicesaswellasupto 450.0mmabovegradelevelwithin3.0mhorizontallyfromanysurfaceof thedevices.(2) Areaswhereflammableliquidsaretransferredshallbeclassifiedasfollows:a) In outdoorareasor wherepositiveandreliablemechanicalventilationis providedin indoorareasinwhichflammableliquidsaretransferredto individualcontainers,suchareasshallbeconsidereda ClassI, Division1locationswithin900.0mmof theventor fill openingextendingin all directionsanda ClassI, Division2 locationwithintheareaextendingbetweena 900.0mmand15mradiusfromtheventor fill ~openingextendinginalldirections,andincludingtheareawithinahorizontalradiusof 3.0mfromtheventor fill openingandextendingto a heightof 450.0mmaboveflooror gradelevels.b) Wherepositiveandreliablemechanicalventilationis notprovidedin indoorareasinwhichflammableliquidsaretransferredto individualcontainers,suchareasshallbeconsideredto bea ClassI, Division1 location.(3) Areasin outsidelocationswhereloadingandunloadingof tankvehiclesandtankcarstakeplaceshallbeclassifiedasfollows:a) Theareaextending900.0mmin all'directionsfromthedome(whenloadingthroughan open dome)or from the vent(whenloadingthrougha closeddomewithatmosphericventing)shallbeconsidereda ClassI, Division1 location.b) The areaextendingbetweena 900.0mmanda 15mradiusfromthedome(whenloadingthroughanopendome)or from,thevent(whenloadingthrougha closeddomewithatmosphericventing)shallbeconsidereda ClassI, Division2 location.300 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIESb) For all typeof above-groundtanks:(4) Areawithinthevicinityof above-groundtanksshallbeclassifiedasfollows:EBCS-10 1995 301d) The areabetween105mand3.0mof aventopeningandextendingin alldirectionsshallbeconsidereda ClassI, Division2 location.c) Any pit or depressionnotwithina Division1 or Division2 locationasdefinedherein,butwhichcontainspiping,valves,or fittingsshallbeconsidereda ClassI,Division2 location.b) Anysuchareasasin (a)above,whenprovidedwithpositiveandreliablemechanicalventilation,shallbeconsidereda ClassI, Division2 location.a) Any pit or depression,anypartof whichlieswithina Division1 or Division2location,unlessprovided'withpositiveandreliablemechanicalventilation,shallbeconsidereda,ClassI, Division1 location.i) theareawithin3.0mfromtheshellends,androofof other'thana floating-roofshallbeconsidereda ClassI, division2 location;andii) wheredikesareprovided,theareainsidethedikeandextendingupwardsto thetopof thedikeshallbeconsideredtobea ClassI, Division2 location.a) The areaabovetheroofandwithintheshellof a floating-rooftypetankshallbeconsidereda ClassI, Division1 location.c) The areawithin 105mof ventopeningand extendingin all directionsshallbeconsidereda ClassI, Division1location.c) The areaextendingwithin900.0mmin alldirectionsfroma fixedconnectionusedin bottomloadingor unloading,loadingthrougha closeddomewithatmosphericventing,or loadingthrougha closeddomewithavapourrecoverysystemshallbeconsidereda ClassI, Division2 locationexceptthat,in thecaseof bottomloadingorunloading,thisclassificationshallalsobeappliedtotheareawithina3.0mradiusfrompointof connectionandextending450.0mmabovegrade.ETHIOPIAN BUILDING CODE STANDARD(6)Garagesinwhichtankvehiclesarestoredor repairedshallbeconsideredto bea ClassI,Division2 locationup to 450.0mmaboveflooror gradelevel.(5)Pitsanddepressionsshallbeclassifiedasfollows:ELECTRICAL INSTALLATION OF BUILDINGS(7) Buildingssuchasofficebuildings,boilerrooms,etcwhichareoutsidethe limitsofhazardousareasasdefinedhereinandwhicharenotusedfor handlingor storingvolatileflammableliquidsor containersfor suchliquidsshallnotbeconsideredto behazardouslocations.13.6.2WiringandEquipmentin HazardousAreas(1) All electricalwiringandequipmentin hazardousareasdefinedin Clause13.6.1shallconformto therequirementsof Section12.13.6.3WiringandEquipmentaboveHazardousAreas(1) Wiring installedabovea hazardouslocationshallconform.to the requirementsofSection8 andbesuitablefor thetypeof buildingsandoccupancy.(2) Fixedequipmentwhichmayproducearcs,sparksor particlesof hot metal,suchaslampsandlampholders,cutouts,switches,socketoutlets,motorsorotherequipmenthavingmake-and-breakor slidingcontacts,shallbeof thetotallyenclosedtypeor soconstructedasto preventtheescapeof sparksor hotmetalparticles.(3) Portablelampsor utilizationequipmentandthe flexiblecordssupplyingthemshallconformto therequirementsof Section12for theclassof locationabovewhichtheyareconnectedor used.(4).All non-current-carryingmetalpartsof equipmentandracewaysshallbe bondedtoearthin accordancewithPartI of Section7 of thisCode.13.7 FINISlllNG PROCESSES13.7.1HazardousLocations(1) The followingareasshallbeconsideredto beClassI, Division1locations:a) The interiorsof sprayboothsandtheirexhaustducts.b) All spacewithin6.0mhorizontallyin anydirection,andextendingto a heightof900.0mmabovethegoodsto bepainted,fromsprayingoperationsthataremoreextensivethantouch-upsprayingandnotconductedwithinthespraybooth.302 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIESc) All spacewithin6.0mhorizontallyin anydirectionfromdip tanksandtheirdrainboards,suchspaceextendingto a heightof 900.0mmabovethediptankanddrainboard.d) All otherspaceswherehazardousconcentrationsof flammablevapoursarelikelytooccur.(2) For sprayingoperationswithinan openfacespraybooth,theextentof theClassI,Division2 hazardouslocationshallbenotlessthanthefollowing:a) Wheretheventilationsystemis interlockedwith thesprayingequipmentso astomakethe sprayingequipmentinoperablewhentheventilationsystemis I}ot inoperation,thespaceshallextendat least105mfromtheopenfaceof thespraybooth.b) Wheretheventilationsystemis not interlockedwiththesprayingequipmentso asto makethesprayingequipmentinoperablewhentheventilationsystemis not inoperation,thespaceshallextendat least3.0mfromtheopenfaceor frontof the.spraybooth.(3) All spacewithintheroom,butbeyondthelimitsfor ClassI, Division1 locationasclassifiedin (1)abovefor extensiveopenspraying;for diptanksanddrainboardsandforotherhazardousoperations,shallbeconsideredto beClassI, Division2 location.(4) Adjacentareaswhichareacutoff fromthedefinedhazardousareabytightpartitionswithoutcommunicatingopenings,andwi~hinwhichhazardousvapoursarenotlikelytobereleased,shallbeclassifiedasnon-hazardous.(5) Dryingand bakingareasprovidedwith positivemechanicalventilationto preventformationof flammableconcentrationofvapoursandprovidedwitheffectiveinterlockstode-energizeall electricalequipmentnot approvedfor ClassI locations,in casetheventilatingequipmentis inoperative,maybeclassifiedasnon-hazardous.(6)Notwithstandingtherequirementsof(lb) above,whereadequatemechanicalventilationwitheffectiveinterlocksisprovidedatfloorlevel:a) thespacewithin900.0mmhorizontallyin anydirectionfromthegoodstobepaintedandsuchspaceextendingto a heightof 900.0mmabovethegoodsto bepaintedshallbeconsidereda ClassI, Division1 location;andETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 303,ELECTRICAL INSTALLATION OF BUILDINGSb) allspacebetweena900.0mmand 105mdistanceabovethegoodsto bepaintedandall spacewithin6.0mhorizontallyin anydirectionbeyondthelimitsfor ClassI,Division1 locationshallbeconsidereda ClassI, Division2 location.(7) Notwithstandingtherequirementsof (2)abovewhereabaffleof sheetmetalof notlessthan1.25mmis installedverticallyabovethefrontfaceof anopen-facesprayboothto aheightof 900.0mmor to theceiling,whicheveris lowerandextendingbackon thesideedgesfor adistanceof 105m,thespacebehindthisbaffleshallbeconsideredto bea non-hazardouslocation.13.7.2WiringandEquipmentin HazardousAreas(1) All electricalwiring and equipmentwithin the hazardousareasas definedInClause13.7.1shallconformto therequirementsof Section12.(2).Unlessspecificallyapprovedforbothreadilyignitabledepositsandflammablevapourlocation,no electricalequipmentshallbe installedor usedwhereit maybe subjectto ahazardousaccumulationof readilyignitabledepositsor residue.(3) Illuminationof readilyignitableareathroughpanelsof glassor othertr~nsparentortranslucentmaterialsispermissibleonlywhere:a) fixedlightingunitsareusedasthesourceof illumination;b) thepanelis noncombustibleandeffectivelyisolatesthehazardousareafromtheareainwhichthelightingunitis located;c) thelightingunitis acceptablefor itsspecificlocation;d) thepanelis of a materialor issoprotectedthatbreakagewillbeunlikely;e) the arrangementis suchthatnormalaccumulationof hazardousresidueon thesurfaceof thepanelwill notberaisedto a dangeroustemperaturebyradiationorconductionfromthesourceof illumination.(4) Portableelectriclampsor otherutilizationequipmentshall:a) notbeusedwithina hazardousareaduringoperationof thefinishingprocess;b) beof a typespecificallyapprovedfor ClassI locationswhenusedduringcleaningor repairingoperations.(5) Notwithstandingtherequirementsof (2)above:304 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIESa) totallyenclosedandgaskettedlightingmaybeusedon theceilingof a sprayroomwhereadequateandpositivemechanicalventilationisprovided;andb) infra-redpaint-dryingunitsmaybe utilizedin a sprayroomif the controlsareinterlockedwiththoseof thesprayingequipmentsuchthatbothoperationscannotbeperformedsimultaneol,lsly;andif portable,thepaintandthedryingunitshallnotbebroughtintothesprayroomuntilthesprayingoperationshaveceased.13.7.3WiringandEquipmentaboveHazardousAreas(1) All fixedwiringabovehazardousareashallconformto theprovisionsof Section8.(2) Equipmentwhichmayproducearcs,sparks,orparticlesofhotmetal,suchaslampsandlampholdersfor fixedlighting,cutouts,switches,receptacles,motorsor otherequipmenthavingmake-and-breakorslidingcontacts,whereinstalledaboveahazardousareaor aboveanareawherefreshlyfinishedgoodsarehandled,shallbeof thetotallyenclosedtypeorsoconstructedasto preventtheescapeof sparksor hotmetalparticles.(3) All metalracewaysandall non-current-carryingmetalportionsof fixedor porta~leequipment,regardlessof voltage,shallbebondedto earthin accordancewith,PartI ofSection7 of thisCode.'13.8 AIRCRAFf HANGARS13.8.1HazardousAreas(1) Any pit or depressionbelowthelevelof thehangarfloorshallbeconsideredto beaClassI, Division1 locationwhichshallextendupto thefloorlevel.(2) The entireareaof thehangar,includinganyadjacentandcommunicationareas~otsuitablycutoff fromthehangarshallbeconsideredtobeClassI, Division2 locationuptoa level450.0mmabovethefloor.(3) The areawithin105mhorizontallyfromaircraftpowerplants,aircraftfuel tanks,oraircraftstructurescontainingfuelshallbeconsideredto bea ClassI, Division2 locationwhichshallextendupwardfromthefloorto a level1.5mabovetheuppersurfaceof wingsandof engineenclosures.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 305'ELECTRICAL INSTALLATION OF BUILDINGS(4) Adjacentareain whichhazardousvapoursarenotlikelytobereleased,suchasstockrooms,electricalcontrolrooms,andothersimilarlocations,maybe classifiedas non-hazardouswhenadequatelyventilatedandwheneffectivelycutoff fromthehangaritselfin accordancewiththeprovisionsof Section12.13.8.2WiringandEquipmentin HazardousAreas(1) All fixedandportablewiringandequipmentwhichis or maybeinstalledor operatedwithin anyof the hazardouslocationsdefinedin Clause13.8.1shall conformto therequirementsof Section12.(2) All wiringinstallationin or underthehangarfloorshallconformto therequirementsfor ClassI, Division1 locations.(3) Wiringsystemsinstalledin pitsor otherspacesin or underthehangarfloorshallbeprovidedwithadequatedrainageandshallnotbeplacedinthesamecompartmentwithanyotherserviceexceptpipedcompressedair.(4) Attachmentplugsandsocketoutletsin hazardouslocationsshallbeexplosion-proof?rshallbeso designedthattheycannotbeenergizedwhiletheconnectionsarebeingmadeor broken.13.8.3WiringNotwithinHazardousArea(1) All fixedwiringin a hangernotwithin'ahazardousareaasdefinedin Clause13.8.1shall be installedin metalracewaysor shallbe armouredcable,Type MI (Mineral-Insulated)cable,or aluminiumsheathedcable,exceptthatwiringin a non-hazardouslocationassetoutin 13.8.1(4)maybeof anytyperecognizedin Section8 assuitableforthetypeof buildingandtheoccupancy.(2) For pendants,flexiblecordof thehard-usagetypeandcontaininga separatebondingconductorshallbeused.(3) For portableutilizationequipmentandlamps,flexiblecordapprovedfor hardusageandcontaininga separatebondingconductorshallbeused.(4) Suitablemeansshallbeprovidedfor maintainingcontinuityandadequacyof bondingbetweenthe fixedwiringsystemandthenon-current-carryingmetalportionsof pendantfixtures,portablelampsandotherportableutilizationequipment.306 EBCS-10 1995 ETHI9PIAN BUILDING CODE STANDARDSECTION 13: FLAMMABLE LIQUID DISPENSING AND OTHER FACILITIES13.8.4EquipmentNotwithinHazardousAreas(1) In locationsotherthanthosedescribedin Clause13.8.1,equipmentwhichis lessthan3.0mabovewingsandengineenclosuresof aircraftandwhichmayproducearcs,sparks,orparticlesof hotmetal,suchaslampsandlanipholdersfor fixedlighting,cutouts,switches,socketoutlets,chargingpanels,generators,motorsor otherequipmenthavingmake-and-breakor slidingcontacts,shallbeof totally-enclosedtypeorso constructedasto preventescapeof sparksor hot metalparticles,exceptthatequipmentin areasdescribedin13.8.1(4)maybeof generalpurposetype.(2) Lampholdersof metal-shell-fibre-linedtypesshallnotbeusedfor fixedlighting.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 307SECTION 14PATIENT CARE AREAS14.1 SCOPE(1) ThisSectionof theCodeappliestotheinstallationofelectricalwiringandequipmentwithinpatientcareareasof hospitalsand thoseportionsof the ele~tricalsystemsofhospitalsdesignatedasessentialelectricalsystems.14.2 NORMATIVEREFERENCES(l) Thefollowingreferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeS~dardonElectricalInstallationof Buildings:.a) C22.1:1990 GanadianElectricalCode, Part I, SafetyStandardforElectricalInstallations,SixteenthEdition.b) NEC (Handbook):1991NationalElectricalCodeHandbook,Basedon the.1991(NEC), SeventeenthEdition.14.3 DEFI~ITIONS(1) For thepurposeof thisSection,in additionto thetermsdefinedin Section1, thefollowingdefinitionsshallapply:anaesthetizinglocationappUedpart308 EBCS-10 1995any areaof a healthcarefacilitywherethe inductionandmaintenanceof..generalanaesthesiaareroutinelycarriedoutinthecourseof theexaminationor treatmentof patients.thepartorpartsof medicalelectrical'equipmentincludingthepatientleadswhichcomeintentionallyinto contact'Wi.,ththepatienttobeexaminedor treated.ETHIOPIAN BUILDING CODE STANDARDSECTION 14: PATIENT CARE AREASbodycontact anintentionalcontactattheskinsurfaceor internally,burnotdirectlyto theheart.cardiaccontact an intentionalcontactdirectlyto the heartby meansof aninvasiveprocedure.casualcontact contactbyvoluntaryactionwitha devicethathasno appliedpart.andis notintendedto beconnectedto a patient.criticalcarearea apatientcareareainwhichanaestheticsareadministered,or inwhichcardiaccontactbetweenapatientandmedicalelectricalequipmentis frequentor normal.delayedvitalbranch that portionof an essentialelectrical'system'inwhich thecircuitsrequirepowerrestorationwithin2.0min.emergencysupply oneor morein-housegeneratorsof electricityintendedto beavailablein theeventof a failureof all othersuppliesandcapableof supplyingall theessentialloads.essentialelectricalsystem anelectricalsystemwhichhasthecapabilityof restoringandsustainingasupplyof electricalenergytospecifiedloadsin theeventof a lossof thenormalsupplyof energy.hazardindex for a givensetof conditionsin anisolatedpowersystem,thecurrent,expressedin milliamperesandconsistingof resistiveand capacitiveleakageand fault currents,thatwould flowthroughlow impendenceif the low impendencewereto beconnectedbetweeneitherisolatedconductorandground.hospital an institution,sodesignatedbyEthiopianMinistryof Health,wherepatientsareaccommodatedonthebasisofmedicalneedandareprovidedwithcontinuingmedicalcareandsupportingdiagnosticandtherapeuticservices.intermediatecarearea apatientcareareainwhichbodycontactbetweenapatientandmedicalelectricalequipmentis frequentor normal.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 309ELECTRICAL INSTALLATION OF BUILDINGSisolatedsystemline isolationmonitornormalsupplypatientpatientcareareapatientcarelocationanelectricaldistributi.onsysteminwhichnocircui.tconductorisconnecteddirectlytoearth.adevicewhichmeasuresanddisplaysthetotalhazardindexonan isolatedelectricalsystem,andprovideswarningwhentheindexreachesa presetlimit.themainelectricalsupplyintoabuildingor buildingcomplex,andmayconsistof oneor moreconsumerservicescapableofsupplyingall loadsin thebuildingcomplex.a personundergoingmedicalinvestigationor treatment.an area intendedprimarilyfor the prqvisionof diagnosis,therapy,or care.a zonein a patientcareareawhichhasbeenpre-selectedfortheaccommodationof apatientbed,table,orothersupportingmechanism,andfortheaccommodationofequipmentlnvolvedin patienttreatment,andwhichincludesthespacewithintheroom 1.5mbeyondthe perimeterof the bed in its normallocationandtowithin203mof thefloor.patientcar~locationbondingpointpermanentlyconnectedequipmenta commonbus at a patientcarelocation,thatisbondedtoearth,andthatservesasacommonpointt6whichequipmentandotherbondingconnectionscanbemadebymeansof a groupof-jacks.equipmentthatiselectricallyconnectedtothesupplybe' meansof connectorsthat can be accessed,loosenedor tightenedonlywiththeaidof a tool.totalhazardindexvitalbranch310 EBCS-10 1995thehazardindexof agivenisolatedsystemwithallappliances,includingthelineisolationmonitor,connected.that portionof an essentialelectricalsystemin whichthecircuitsrequirepowerrestorationwithin10.0s.ETHIOPIAN BUILDING CODE STANDARDSECTION 14: PATIENT CARE AREAS14.4 CIRCUITS IN BASIC CARE AREAS14.4.1BranchCircuits(1) Thebranchcircuitssupplyingsocketoutletsandpermanentlyconnectedequipmentinbasiccareareasshallbesuppliedfromaneartheddistributionsystem.(2)A branchcircuitwhichsuppliessocketoutletsor permanentlyconnectedmedicalelectricalequipmentwithina patientcarelocationshallonlysupplyloadswithinsuchlocation.(3)All branchcircuitsfor a patientcare locationshall be suppliedfrom a singlepanelboard,exceptbranchcircuitsintendedto bepartof anessentialelectrical'system,whichshallthenbepermittedto besuppliedfromtwopanelboards,oneof whichis partoftheessentialsystem.14.4.2BondingtoEarth in BasicCareAreas(1)Bondingconductorsshallbeinsulatedunlesstheyare:a) installedin nonmetallicconduit;orb) incorporatedinto a cableassemblyin sucha mannerthatcontactbetweenanymetalshieldor armour,if it is present,and a barebondingconductoris notpossible.'(2)All socketoutletsandotherpermanentlyconnectedequipmentshallbebondedtoearthbycopperequipmentbondingconductors,sizednotsmallerthantheminimumsizerequiredforcircuitconductorsand,exceptaspermittedbythesupplyingauthority,runwith thecircuitconductorsin accordancewiththefollowing:a) Eachmulti-wirebranchcircuitshallbeprovidedwithitsownequipmentbondingconductor.b) Exceptaspermittedby(c) and(d) below,each2-wirebranchcircuitsupplying-asocketoutletat apatientcarelocationshallbeprovidedwithitsownequipmentbondingconductor.c) Whenthesocketoutletsat a patientcarelocationaresuppliedfromtwo2-wirebranchcircuitsin thesameraceway,asingleequipmentbondingconductorshallbe- permittedto besharedbythetwocircuits.ETHIOPIANBUILDING CODE STANDARD EBCS-10 1995 311,ELECTRICAL INSTALLATION OF BUILDINGSd) When socketoutletintendedfor a pair of adjacentpatientcarelocationsaresuppliedbythree2-wirebranchcircuitsandoneof thecircuitsis intendedto besharedbybothpatientcarelocations,thethreecircuitsshallbepermittedtosharetwoequipmentbondingconductors.(3) Equipmentbondingconductorsrequiredby(2)and(5)belowshallterminateeitheratthepanelboardsupplyingthebranchcircuitsto thepatientcarelocationfromwhichtheyariseor onanearthingbuswhichis bondedto thatpanelboard.(4) Eachitemof 3-phaseequipmentshallbebondedtoearthwithanequipmentbondingconductorwhichis:a) sizedin accordancewithPartI of Section7of thisCode,butin nocasesmallerthan4.0mm2;andb) connectedto itsownterminalattheequipmentandthepanelboard.(5) Exposednon-curr9nt-carryingmetalpartsof communication,radio or televisionequipment,otherthantelephonesets,at a patientcarelocation,if theycouldbecomeenergized,shallbebondedto earthby:a) connectionto thebondingscrewin thecommunicationsectionof a buriedandgangedmetaloutletbox,serv~ngapatientcarelocation;orb) connectiontoanequipmentbondingconductororearthingbusforthatpatientcarelocationasidentifiedin (3)above.14.4.3 SocketOutletsin Basic-CareAreas(1) Socketoutletsintendedfor a givenpatient-carelocationshallbe locatedso astominimizethelikelihoodof theirinadvertentuseforapatient-carelocationforwhichtheyarenotintended.(2) Socketoutletswhicharelocatedinareasthatareroutinelycleanedusingliquidswhichnormallysplashagainstthewallsshallbeinstallednotlessthan300.0mmabovethefloor.(3) Socketoutletslocatedin bathroomsorwashroomswithinapatientcareareashallbelocated:a) adjacentto thewashbasin,andb) outsideof anybathtubenclosureor showerstall.312 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD14.5.1BranchCircuits14.5 CIRCUITS IN INTERMEDIATE AND CRITICAL-CARE AREAS14.5.2Bondingto Earthin IntermediateandCritical-CareAreasEBCS-10 1995 313a) meettherequirementsof Clause14.4.3;andb) wheresuppliedfromanisolatedsystem,beso identified.(4) Socketoutletswhicharelocatedadjacenttoawashbasinin apatientcareareashallbeprotectedbyanearthfaultcircuitinterrupterof theClassAt type.a) a bondingjumperconnectingit to thebondingterminalin an enclosurewhichaccommodatesthebondingpointalongwith socketoutletsfor a patientcarelocation;orb) a copperconductorwhichis installedfor thatspecificpurpose,andis run in thesameracewayas the equipmen.tbondingconductorsservingthatpatientcarelocation.SECTION 14: PATIENT CARE AREASt For definitionof ClassA earth-faultcircuitinterrupter,referto ClauseA.2,AnnexA, Section25.(1) The branchcircuitssupplyingspcketoutletsand other permanentlyconnectedequipmentin intermediateor criticalcareareas.shallbe suppliedfromeitheranearthsystemmeetingthe requirementsof Section14.4or an isolatedsystemmeetingtherequirementsof Section14.6,exceptthatall branchcircuits,otherthanthosesupplyingmultiphaseequipment,shallbe2-wirecircuits.(1) Bondingtoearthin intermediateandcriticalcareareasshallconformtoClause14.4.2whetherthesupplyis derivedfromanearthedor anisolatedsystem.(2) If a patient-care-Iocationbondingpoint is provided,it shall be bondedto thepanelboardservingthepatient-carelocationwithwhichit is associatedbyeither:(1) Socketoutletsin intermediateandcriticalcareareasshall:ETHIOPIAN BUILDING CODE STANDARD14.5.3Receptaclesin IntermediateandCriticalCareAreasELECTRICAL INSTALLATION OF BUILDINGS14.6 ISOLATED SYSTEMS14.6.1 Sourcesof Supply(1) The meansof supplyto anisolatedsystemshallbe:,a) thesecondaryof oneor moreisolatingtransformersh*ing no directelectricalconnectionbetweenprimaryandsecondarywindings,b) a motor-generatorset,orc) a suitablyisolated,battery-poweredinvertersupply.(2) Wheremorethanonesingle-phaseisolatedpow~rsystemservesasinglelocation,theearthingbussesof all of thesesystemsshallbe bondedtogetherwitha copperbondingconductor:a) havinga totalimpedancenotgreaterthanO.2ohm,andb) sizednotsmallerthanthatpermittedin Part I of section7 of thisCode.14.6.2 Single-PhaseIsolatedCircuits(1) Isolatedcircuitsshall:a) notbedeliberatelyearthedexceptthroughtheimpedanceof anisolationsensingdevice(e.g.,isolationmonitor);b) have-overcurrentdevicesthatwill openallunearthedconductorssimultaneously;c) unlessprohibitedby the PowerSupplingAuthority,be installedin non-metalraceways.(2) Anydisconnectingmeanscontrollinganisolatedcircuitshallsafelyandsimultaneouslydisconnectallunearthedconductors.(3) A single-phaseisolatedsystemshallincludeautomaticmeans(alineisolationmonitor),with an indicatorlocatedwherevisibleto personsusingthe system,to monitortheimpedance-to-earthof thesystemtogetherwithanyloadsconnectedto it.(4) Wherea single-phaseisolatedsystemis employed,it shallsupply:a) general-purposesocketoutletsat:314 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 14: PATIENT CARE AREASi) a singleanaesthetizinglocation;ii) oneor morepatientcarelocationsin a singleroom;oriii) a maximumof twopatientcarelocationsin separatebut adjacentrooms,providedthatthealarmindicatorclearlyidentifiesthepatientcarelocationsaffectedbythefault;orb) specialpurposesocketoutletsatdifferentlocationsor indifferentrooms,providedthatthesystemisusedonlyfor theonepurpose,andisarrangedsothatonlyonesocketoutletscanbeenergizedata time.(5) A single-phaseisolatedsystemwhichsuppliesonlya singleloadvia a singlebranchcircuitshallmeettherequirementsof (1) through(3)aboveexceptthat:a) overcurrentdevicesneednotbeinstalledin theisolatedcircuit;andb) theuseof a line-isolationmonitorshallbeoptional.14.6.3Three-PhaseIsolatedSystems(1) A three-phaseisolatedsystemshall:a) supplyonlypermanentlyconnectedequipment;andb) meettherequirementsof Clause14.6.1.14.7 ESSENTIAL ELECTRICAL SYSTEMS14.7.1Circuitsin EssentialElectricalSystems(1) An essentialelectricalsystemshallcomprisethosecircuitsthatsupplyloadsdesignatedbythehospitaladministrationasbeingessentialfor thelifesafetyandcareof thepatient,andtheeffectiveoperationof thehospital.(2) An essentialelectricalsystemshallcompriseat leasta vitalbranch,andmayalsoincludea delayedvitalbranch.(3) Thewiringof theessentialelectricalsystemshallbekeptentirelyindependentof allotherwiringandequipmentandshallnotenteraftxture,raceway,boxorcabinetoccupiedbyotherwiringexceptwherenecessaryasin:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 315'ELECTRICAL INSTALLATION OF BUILDINGSa) transferswitches;andb) emergencylightingfixturessuppliedfromtwosources.14.8 TRANSFER SWITCHES(1) All transferswitchesshallbeacceptableto thesupplyauthority.(2) Automatictransferswitchesusedin essentialelectricalsystemsshall:a) beelectricallyoperatedandmechanicallyheld;andb) includemeansfor safemanualoperation.(3) Manualtransferswitchesshallconformto thefollowing:a) Theswitchingmeansshallbemechanicallyheldandtheoperationshallbebydirectmanpowerorbyelectricalremotemanualcontrolutilizingcontrolpowerfromthesupplytowhichtheloadis beingtransferred.b) A manualtransferswitchwhichis operatedbyelectricalremotemanualc.pntrolshallincludea meansfor safemanualmechanicaloperation.c) Reliablemechanicalinterlocking(and,fn thecaseofaswitchoperatedbyelectricalremotemanualcontrol,electricalinterlocking)to preventinterconnectionof thenormalandtheemergencysuppliesof powershallbe inherentin thedesignof amanualtransfertlwitch.d) A manualtransferswitchshall includea readilyvisiblemechanicalindicatorshowingtheswitchposition.(4) Thevitalanddelayedvitalbranchesshallbeconnectedtotheemergencypowersupplybymeansof oneor moreautomatictransferswitches.14.9 EMERGENCY SUPPLY(1) An emergencysupplyshallbeoneormoregeneratorsetsdrivenbyaprimemoverandlocatedonthehospitalpremisesinafire-resistantenclosureorroom,andinsuchamannerasto minimizethepossibilityof floodinganddamage.316 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 14: PATIENT CARE AREAS(2) Theprimemoverof thegeneratingset,asspecifiedin (1) above,shallbecapableofoperatingindependentlyof suppliesofwaterandfuelfrompublicutilities.(3) A fuelsupplysufficienttooperatetheprimemoverunderfullloadforatleast24.0hrsshallbestoredon thesite.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 317SECTIONINSTALlATION OF liGHTING EQUIPMENf15.1 SCOPE(1) This Sectionappliesto installationof interiorandexteriorlightingequipment.15.2 NORMATIVEREFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationof Buildings.(a) C22.1:1990(b) IEE:1970(c) BS 8208:1985(d) BS5649(EN40):1978:CanadianElectricalCode,Part 1,SafetyStandardfor ElectricalInstallation,SixteenthEdition.TheInstituteofelectricalEngineers,RegulationsfortheElectricalEquipmentof Buildings,FourteenthEdition,IncorporatingAmendments.British Standard,Artificial Lightingfor Interior,Part 1.BritishStandard,LightingColumnsParts1,2,4,5,6,and 9.15.3 INTERIORLIGlITING EQUIPMENT15.3.1 General15.3.1.1 Material(1) Materialof lampsshallconfirm,asregardsthetypeof lamp,mechanicalqualitiesandinsulationresistance,to applicableIEC or otherinternationalstandards.318 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENT15.3.1.2 Luminaire Construction(1) Luminairesshallbeconstructedfromsuchmaterialandsofinishedthattheirsafety,performanceorappearancedoesnotdeterioratesignificantlyduringnormallifewhentheyareoperatedin theconditionforwhichtheyaredesigned.15.3.1.3Voltage(1) Branchcircuitvoltagesshallnotexceed230.0V-to-earthindwellingunits;andin otherthandwellingunits,voltagesshallnotexceedthevoltage-to-earthofnominalsystem380.0V.Note: Where380.0Vline-to-linesystemis used,thecontrolswitchshallbe of double-poletypeandtheluminaireshallbeearthed.15.3.1.4 Pro.tection(1) Incandescentluminairesandincandescentlampholdersshallnotbeconnectedto abranchcircuitprotectedbyovercurrentdevicesratedatmorethan16.0A; butinotherthan..dwellingunits,theyshallbepermittedto b~connectedto a branchcircuitprotectedbyoverC4rrentdevicesratedor setatnotmorethan20.0A.(2) Tungstenhalogenluminaries,incandescentmoulded-baseluminaries,andincandescentmoulded-baselampholdersshall not be connectedto branchcircuit protectedbyovercurrentdevicesratedor setatmorethan40.0A.(3) Fluorescentluminariesshall not be connectedto a branchcircuitprotectedbyovercurrentdevicesratedorsetatmorethan16.0Aexceptforcircuitssupplyingfluorescentluminaries;onlytheratingof theovercurrentprotectionmayexceed16.0A,butshallnotexceed20.0A.(4) High intensitydischarge(HID) luminariesshallnotbeconnectedto a branchcircuitprotectedbyovercurrentdevicesratedor setatmorethan:~ 20.0Awheretheinputvoltageto theluminaireis notmorethan230.0Vnominal,butnotexceeding380.0Vnominal;andb) 16.0Awheretheinputvoltageis above380.0Vnominal.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 319ELECTRICAL INSTALLATION OF BUILDINGS15.3.2 Locationof LightingEquipment15.3.2.1Nearorovercombustiblematerial(1) Luminariesandlampholdersshallbeplacedorguardedinsuchamannerastopreventignitionof anycombustiblematerials.(2) Any shadeor guardusedfor thepurposein (1) aboveshallbe,besideslimitingthetemperaturetowhichthecombustiblematerialmaybesubjected,suitabletowithstandtheheatfrom thelamp.15.3.2.2 Show'windows(1) In showwindows:a) no luminarieshavingexposedwiringotherthana luminaireof a chain-suspensiontypeshallbeused;andb) no lampholdershavinga paper-fibberliningshallbeused.15.3.2.3 Clothesclosets(1) Luminairesinstalledin clothesclosets:a) shallbe locatedon theceilingor on thefrontwall abovethedoorof theclosetunlessmountedonthetrimof the,sidewallsof thedoorwayandapprovedfor theapplication;andb) shallnotbeof pendanttype.15.3.2.4Luminairein dampor wetlocations(1) Luminariesin damporwetlocationsshallbeapprovedfor suchlocationsandbesomarked.15.3.2.5 Controlswitch(1) A lightfittingconnectedtoaninstallationbymeansotherthanasocketoutletshallbecontrolledbya switchwhichshallbearrangedtodisconnectall thesupplyconductors.320 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENT(2) Theswitchrequiredby(1)aboveshallbeseparatefromlightingfittingandin areadilyaccessiblepositionsubjectto theprovisions(3) and(5)below,whereapplicable.(3) Whereaswitchhastobesituatedsoastobenormallyinaccessibleto apersonwhoisusingabathor ashower,it'isadmissiblefor theswitchtobeplacedadjacenttothenormalaccessdoorof theroom,or to beof thetypeoperatedbyinsulatingcord.(4) The switchor switchesprovidingcontrolof comprehensivelightinginstallation.::omprisingmorethanonelightingfittingin non-domesticpremisesmaybe installedinseparaterooms.(5) Wherelightingfittingsareinstalledoverreadilycombustiblematerial,everylightfitting.shallbecontrolledbyanindividualwallswitch.(6) Where st~irwayin a dwellingunit has risers,the lightingshallbe controlledbyintermediatewallswitchesortheirfunctionalequivalentlocatedatthehead.andfootof the'stairway.15.3.3Installationof LightingEquipment15.3.3.1Liveparts(1) Luminaries,lampholders,androsettesshallbeinstalledsothatnolivepartisexposedtocontactwhiletheyarein use.(2) Wherelampholdersandswitcheshaveexposedaccessibleterminals,,theyshallnotbeinstalledin metalluminairecanopiesor in openbasesof portablelamps.15.3.3.2Supports(1) Everyluminaire,lampholderandrosetteshallbesecurelysupported.(2) Wherea luminaireweighsmorethan30.0Nor exceeds40.0cmin anydimension,itshallnotbesupportedbythescrewshellof thelampholders.(3) Whereanon-metallicoutletboxofthermoplasticmaterial,suchas,forexample,P.V.C,isusedto suspenda luminaire,careshallbetakento ensurethatthetemperatureof theboxdoesnotexceed600Cjandthemasssuspendedshallnotexceed30.0N.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 321ELECTRICAL INSTALLATION OF BUILDINGS(4) Wheretheweightof a luminairedoesnotexceedlOO.ON,it shallbepermittedto besupportedbyanoutletboxthatis mountedona barhanger.(5) WherealuminaireweightsmorethanlOa.ON,it shallbesuspendedindependentlyoftheoutletbox,or bymeansof anacceptablefixturehangerwithintegraloutletbox.15.3.3.3 Outletboxestobecovered(1) Everyoutletboxusedwithlightingequipmentshallbeprovidedwithacoverorcoveredbya luminairecanopylampholder,rosette,or otherdevice.15.3.3.4Recessedluminaries(1) The recessedportionof everyenclosureof a recessedluminaireshallbe at least12.5mmfromcombustiblematerialateverypointotherthanat apointof support.(2) Everyrecessedluminaireshallbe,soinstalledthatanyadjacentcombustiblematerialis notsubjectedto temperaturein excessof 90oe. (3) Recessedluminariesshallnotb,eusedwhenblanketedwiththermalinsulationunlesstheluminariesaremarkedandapprovedfor thisuse.15.3.3.5Minimumheightof luminaries(1) Wherea rigidluminaireor lampholderis locatedata heightof lessthan2.1mabovethe floor andis readilyaccessible,theluminaireor lampholdershallbeprotectedfrommechanicalinjurybya guardor bylocation.15.3.3.6Luminaireexposedtoflyingobjects(1) Whereluminariesareinstalledingymnasiumsorsimilarlocationswherethelampsarenormallyexposedto damagefromflyingobjects,thelampshallbeguardedbyoneof thefollowingmeans:a) metalreflectorsthateffectivelyprotectthelamps,b) metalscreens,c) enclosuresof armouredglassor suitableplasticmaterial.322 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENT15.3.3.7Luminaireasa raceway15.3.4 Wiringof LightingEquipmentEBCS-10 1995 323ETHIOPIAN BUILDING CODE STANDARDa) havea temperatureratingnotlessthan90C;b) beof typelistedin:a) aninstallationof luminariesapprovedandmarkedforend-to-endassemblytoforma continuouschannel;orb) luminarieswhichareconnectedtogetherbyacceptablewiringmethods.i) Section4,Annex:S,asbeingsuitablefor usein raceway;orii) Section4,AnnexB, asbeingsuitablefor use'inaccordancewiththisClause,providedthatconductorsare not smallerthan 2.5mm2and do not extend'beyondtheluminariesthroughracewaymorethan2.0mlong.a) beneatlyarrangedwithoutexcesswiring;b) benotexposedtomechanicalinjury;c) be arrangedso thatit is not subjectto temperaturesabovethosefor whichit isapproved;andd) be freefromjoint or tapwithinanarmor stem.(1) Notwithstandingtherequirementsof Section4 with regardto thecoloursusedforidentifyingconductors,a continuous-colouredtracerin thebraid~findividualbraidedconductorshallbepermittedfor thesupplyconductorsof a luminaire.(1) AIl electricalwiringonorwithin-aluminaire,-besideensuringitselectricalsafety,shall:15.3.4.1Wiringof luminaries(2) Ballastslocatedwithinluminariesshallbe deemedto be sourcesof heatand'theconductorssupplyingthellminariesshall:15.3.4.2Colourcoding(1) Branchcircuitconductorsrun througha luminaireshallbe containedin a racewaywhichis anintegralpartof theluminaireexceptthattheconductorof a2-wire,3-wire,or4-wirebranchcircuitsupplyingtheluminairemaybecarriedthrough:I'ELECTRICAL INSTALLATION OF BUiLDINGS15.3.4.3Conductorcrosssectionandinsulation(1) LuminariesshallbewiredwithaconductoratleastO.5mm2crosssectionalarea,havinginsulationsuitableforvoltageandtemperatnretowhichtheconductorsmaybesubjected.15.3.4.4Conductoron movableparts(1) Strandedconductorsshallbeusedonchain-typeluminaireandothermovablepartsoflightingequipment.(2) Conductorsshallbearrangedsothattheweightoftheluminaireor thatof themovablepartsdo.esnotplaceunduetensionontheconnections.(3) All conductorswhichsupplymovablepartsof lightingequipmentshallbeprotectedagainstmechanicalinjury.15.3.4.5Pendantconductors(1) Wherependantconductorsarelongerthan900.0mm,theyshallbetwistedtogether.15.3.4.6Recessedluminaire wiring(1) Conductorsforwiringrecessedluminaire,branchcircuitandtapconnectionshallhaveinsulationsuitablefor thetemperatureencountered.(2) Branchcircuitconductorsshallbepermittedto berundirectlyto theluminaire.(3) Tap connectionon'conductorsshall:a) notbesmallerthan1.0mm2copperruninafactory-installedracewayor,if racewayis providedbutnotfactoryassembled,smallerthan2.5mm2;b) extendat least1S0.0mmfromtheraceway;andc) beinstalledin a racewayextendingatleast450.0mmbutnotmorethan2.0mfromtheluminaire,andterminatein anoutletboxlocatednotlessthan300.0mmfromtheluminaire.(4) The outletboxreferredin (3c)aboveshallbeaccessible,andif accessis throughtheopeningfor mountingtheluminaireor throughsomeotheropeningin theceiling,this324 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENTopeningshallbenotlessthan200.0mmx 200.0mmandtheoutletboxshallbemountedwithin350.0mmof theopening.(5) A supplyconnectionboxformingpartof an approvedluminaireassemblyshallbeaccessible,andif accessis throughtheopeningformountingtheluminaire,thefollowingrequirementsshallbemet:a) The electricalcomponentsof theluminaireshallbe capableof beingextractedthroughtheopeningfor service.b) Thecoverof thesupplyconnectionboxshallbecapableofbeingremovedbyhandtoolheldbelowceiling.(6) Branch-circuitconductorsshallnotpassthroughthesupplyconnectionboxformingpartof anapprovedluminaireassemblyunlesstheluminaireis approvedandmarkedforthepurpose.15.3.4.7Ceilingoutletboxwiring(1) Branch-circuitconductorshavinginsulationsuitablefor 90Cshallbe usedfor thewiringof all ceilingoutletboxesonwhicha luminaireis,or maybe,mounted;andtheampacityof 90Cwireshallbelimitedto theampacityof 60Cwire.15.3.4.8Wiringofshow-windowluminaries(1) Whereshow-windowluminariesare closelyspaced,theyshallbe permittedto beconnectedto c;. conductorsuitablefor thepurposewhichis listedinAnnexB of Section4witha temperatureratingof notlessthan125C.(2) The connectionof show-windowluminariesto thecircuitconductorsshallbe in ajunctionbox;andtheboxshallbemaintainedata sufficientdistancefromtheluminairetoensurethatthecircuitconductorsarenotsubjectedto temperaturein excessof theirrating.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 325..ELECTRICAL INSTALLATION OF BUILDINGS15.3.5 Earth'ingof LightingEquipment15.3.5.1General(1) Non-current-carryingmetalpartsof luminariesandassociatedequipmentshallbeearthedin accordancewithPart I of Section7.15.3.5.2Lampholders(1) Wherecentre-contactscrewlampholdersareconnectedto a sourceof supplyhavingan earthedneutralconductor,theouteror screwedcontactshallbeconnectedto thatconducfor.(2) Wherelampho'ldersin(1)aboveareusedincircuitshavingneitherpoleconnectedwithearthor in anydampsituationinwhichtheycanreadilybetouchedbyapersonin contactwith or standingon earthedmetal,theyshallbe providedwith a protectiveshieldofinsulatingmaterialor shallbeplacedor safeguardedsothatneitherthelampcapnortheoute,ror screwedcontactof thelampholdercaninadverntlybetouchedwhenthel~mpcapis engagedwiththecontact.15.3.6 Electric-DischargeLightingSystemsOperatingat1000.0Vor Less15.3.6.1 Transformer(1) OiHilled transformersshallnotbeused.15.3.6.2 Thermalprotection(1) Luminarieswhichemployfluorescentlampsshallhavethermallyprotectedballastsexceptwheretheballastsareof thesimplereactancetype.15.3.6.3Auxiliaryequipment(1) Reactors,capacitors,resistors,andotherauxiliaryequipmentshallbe:a) enclosedwithintheliminaire,b) enclosedwithinanaccessible,permanentlyinstalled,metalcabinetwhereremotefromtheluminaire,orc) acceptablefor usewithoutanadditionalenclosure.326 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENT- .(2) The metaJcabinet,if notpartof theluminaire,shallbeinstalledascloseaspossibletotheluminaire.(3) Wheredisplaycasesarenotpermanentlyinstalled,nopartof asecondarycircuitshallbeincludedin morethanonecase.15;~.6.4Control(1) The luminaries.andlampinstallationsshallbeCQp.trolledbya switch,circuitbreaker,or contact.or.(2) Wherea switchis usedasin (1)above,it shall:a) havea currentratingof not lessthantwi~ theClfrentratingof the lampsortransformers;b) bea typeapprovedwiththeassembly;orc) bea manually-operatedgeneraluse380.0Va.c.switch.15.4 OUTDOOR LIGHTING EQUIPMENT15.4.1General15.4.1.1Hazard(1) In outdoorlightinginstallations,eitherdecorativelightingor illuminationof outdoorareas,theprotectionof theinstallationandsafetyfromshockhazardsh?-llbe themajorconcernandthefire hazardof theminoror of secondarynature.15.4.1.2Ballastprotection(1) Luminairewhichemployfluorescentlampsshallhwe thermallyprotectedballastsexceptwheretheballastsareof thesimplereactancetype.15.4.1.3Overcurrentpotection(1) Overcurrentprotectionshallnotbeprovidedin ahigh-intensitydischargeluminaireoraseparateballastboxunlessthecombinationis approvedfor thepurposeandsomarked.ETHIOPIAN BUILDING CODE STANDARD -EBCS-10 1995 327ELECTRICAL INSTALLATION OF BUILDINGS15.4.2 PermanentOutdoorFloodlightingInstallation15.4.2.1General(1) Clause15.4.2shallapplytopermanent,outdoorinstallationsof floodlightsof 300.0Wor largerwherethefloodlightsaremountedonpolesor towers.15.4.2.2Serviceequipment(1) Serviceequipmentshallcomplywith Section5 of this Code; andwhereindoorinstallationis installedoutdoors,it shallbe installedin an acceptableweather-proofenclosure.15.4.2.3 Wiringmethodsunderground(1) Undergroundwiringshallberun:a) whereacceptable,in rigidsteelor rigidaluminiumconduit;b) in non-metallicundergroundconduit;c) aslead-sheathedarmouredcable,mineral-insulatedcable,or aluminium-sheathedcable;ord) asconductorsor cableassembliesacceptablefor earthburial.(2) Conductorsburieddirectlyin the earthshallbe of typessuitablefor use in wetlocations..(3) Suitablecorrosion-resistantprotectionshallbeprovidedforaluminIumsheathedcablesandaluminiumconduits,andalsofor mineral-insulatedcable,if usedwherematerialscomingintocontactwiththecablemayhavea deterioratingeffecton thesheath.15.4.2.4 Wiringmethodsonpoles(1) All electricalequipmenton apoleshallbecontrolledbyaswitchwhichcanbelockedinthe'Off'position,andeachpoleshallbeprovidedwithaprominentsignwarningagainstclimbingthepoleuntil theswitchis 'Off' unlessall conductorsandlivepartsotherthanthoseusedfor pole-topwiring are guardedagainstaccidentalcontactin one of thefollowingways:328 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENTa) The conductorsarerunin rigidor flexiblemetalconduit,asin miner~l-insulatedcable,or up thecentreof steel,aluminium,ot hallowconcretepoles;b) The conductorsandlivepartsarekeptat least1.0mfromtheclimbingladderorclimbingstep.c) Barriersareprovidedbetweenconductorsor liveparts,orboth,andtheclimbingladdersoastopreventa likelihoodof contactbytheclimber.(2) Conductorsrunningup thecentreof polesshallbesupportedsoastopreventjnjurytotheconductorsinsidethepoleandsoastopreventunduestrainontheconductorwheretheyleavethepole.(3) Whereverticalconductors,cables,andearthingconductorsarewithin2.5moflocationsaccessibleto unauthorizedpersons,theyshallbeprovidedwith a coveringwhichgivesacceptablemechanicalprotection.(4) Onwoodpoles,forearthingconductorsfromlightningarresters,theprotectivecoveringspecifiedin (3) aboveshallbe of woodmouldingor otherinsulatingmaterialgivingequivalentprotection.(5) Wherethereis morethanonebranchcircuitsona poletop,thefeedersshallberuntoa distributionpanelboardwhichshallbeeitherweather-proofor installedin aweather-proofenclosure.Note: The panelboardmaybeomittedwheretherearetwobranchcircuitsona 230/380.0Ycircuitswithacommonneutrallineandwheretherearethreebranchcircuitsona230/380.0Y,3-phase,4-wirecircuits.(6) Pole-topbranchcircuitwiring,exclusiveof leadsapprovedwithfloodlightstowhichtheyareconnected,shallberun:a) aslead-sheathedcableorrubberorthermoplastic-insulated,moisture-resistanttypesof conductorsinstalledin rigidconduit;orb) byspecialpermission,asinsulatedor uninsulatedexposedwiringprovidedthat:i) thewiringis supportedona suitableinsulator;ii) thewiringis controlledbyaswitchwhichcanbelockedin the'Off' position;andiii) thepoleisprovidedwithaprominentsignwarningagainstclimbingit untiltheswitchis 'Off'.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 329ELECTRICAL INSTALLATION OF BUILDINGS(7) Thereshallbenojointsor splicesconcealedwithinconduit;butopentapsandjointsmaybe madein pole-topexposedwiringprovidedthejoint or lap is giveninsulationequivalentto thaton theconductorsjointed.(8) Transformersshallcomplywiththefollowing:a) If mountedon floodlightpoles,all livepartsshallbeguardedasrequiredby(1)above.b) If mountedon poles,thebottomof thetransformershallbeat least5.0mabovelocationsaccessibleto unauthorizedpersons.c) If locatedonplatformsontheground,theyshallbecompletelyenclosedsoastopreventaccessbyunauthorizedpersonsor theyshallbesurroundedbyaprotectingfence.(9) Switchescontrollingfloodlightsshallcomplywiththefollowing:a) A switchon theprimarysideof a transformershallbe capableof makingandinterruptingthefull-loadonthetransformer.b) Switchescontrollingfloodlightsfromthesecondarysideofatransformershallhave a currentratingnotlessthan125%of thecurrentrequirementsof thefloodlightstheycontrol.c) Switchesshallbe capableof beingoperatedeitherby remoteoperationor byproperguardingwithoutexposingtheoperatortodangerof contactwithliveparts.d) Switchesshallbecapableof beinglockedin the'Off'position.(10) Thesecondaryearthed-circuitconductormaybeearthedbyinterconnectingtotheprimaryearthedcircuitconductorprovidedthat:a) theprimaryis earthedatthetransformers,andb) interconnectionis madeatthetransformer.(11) Exceptfor isolatedmetalpartssuchascrossbars,bolts,insulatorpins,andthelike,all non-current-carryingmetalpartsof theelectricalequipmentat thepole-topshallbebondedtogetherand,if withinreachof anyearthedmetal,theyshallbeearthed.330 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD-SECTION 15: INSTALLATION OF LIGHTING EQUIPMENT15.4.3 ExposedWiringfor PermanentOutdol..Lighting15.4.3.1 General(l) Clause15.4.3shallapplytoexposedwiringforpermanentoutdoorlightingotherthanfloodlightingwherethe circuitsare run betweenbuildiilgs,betweenpoles,or betweenbuildingsandpoles.15.4.3.2 C7olUiuctors(1) Conductorsshallbestrandedcopper,notlessthan2.5m2,andshallbe:a) of a typesuitablefor exposedwiringwhereexposedto theweather;b) of the rubber-insulatedtypesuitablefor exposedwiringwhereexposedto theweatherwhenlampholdersof a typewhichpuncturethe insulationandmakecontactwiththeconductorsareused;orc) of themoisture-resistant,rubber-insulatedtypesuitableforexposedwiringwhereexposedto theweatherif cabledtogetherandusedwithmessengercables.15.4.3.3 Useof insulators15.4.3.3.1Conductorsattachment(1) Conductorsshall be securelyattachedto insulatorsat eachend of the run if amessengeris notusedandattheintermediatepointsof support,if thereareany.15.4~3.3.2Typeof insulator(1) Insulatorsat theendsof runsshallbeof thestraintypeunlesstheconductorsaresupportedbymessengercables.15.4.3.3.3Split knobs(1) Splitknobsshallnotbeused.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 331ELECTRICAL INSTALLATION OF BUILDINGS15.4.3.3.4Heightof conductors(1) Conductorssupplyinglampsinparkinglots,used-carlots,drive-inestablishmentsandsimilarcommercialareasshallbemaintainedsuchthattheconductorsor thebottomof alampfedfromtheconductors,whicheveris lower,shallhavea clearanceof notlessthan4.0mabovegradeatanypointin arun,exceptthatwhereadrivewayor throughfareexists,thisclearanceshallnotbe lessthan4.0m.15.4.3.5 Spacingfrom combustiblematerial(1) Conductorsandlampholdersshallbemaintainedatadistancenotlessthan1.0mfromanycombustiblematerialexceptforbranchcircuitconductorsatthepointof connectionto buildingsor poles.15.4.3.6 Spacingof conductors(1) Conductorsshallbeseparatedatleast300.0mmfromeachotherbymeansof insulatingspacersat intervalsof not morethan4.5munlessthe conductorsare securedt9 and'supportedbymessengercables.15.4.3.7 Lampholders(1) Lampholdersshall:a) beof weatherprooftypes,withmouldedinsulatingbodies;b) beof typeshavingeither:i) permanentlyattachedleads;orii) terminalsof a typewhichpuncturetheinsulationandmakecontactwith theconductors;c) have,whenwithpermanentlyattachedleads,theconnectionto thecircuitwiresstaggeredwherea cabledassemblyis used.332 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENT15.4.3.8 Useof messengercables(1) Messengercables:a) .shallbeusedtosupporttheconductors:i) if lampholdershavingpermanentlyattachedleadsare used,and the spanexceeds12.0m;andii) inallcaseswherelampholdershavingterminationwhichpuncturetheinsulationareused;b) shallbesecurelyattachedateachendof therunandshallbeearthed.15.4.3.9 Constructionof messengercables(1) Messengercablesshallbeofgalvanizedsteel,copper-coatedsteel,orstainlesssteel,andshallbeof a strandedconstructionwithno lessthansevenstrands.(2) The effectiveultimatestrengthof amessengercableshallnotbelessthan3timesthecalculatedmaximumworkingloadandin nocaseshalltheindividualstrandsbelessthan:a) 1.168mmin diameterin thecaseof galvanizedor copper-coatedwire;orb) 1.112mmin diameterin thecaseof stainlesssteelwire.15.4.3.10Branchcircuit loadingandprotection(1) Branchcircuitsshallbeprotectedbyovercurrentdevicesratedatnotmorethan32.0A.(2) The totalloadon abranchcircuitshallnotexceed80%of theratingor settingof theovercurrentdevices.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 333ANNEX A (NORMATIVE)LIGHTING COLUMNSA.i TERMS IN THE FIELD OF LIGHTING COLUMNSLightingcolumnnominalheighta supportintendedto holdoneor morelanterns,consistingof oneof moreparts:a post,possiblyanextensionpieceand,if necessary,a bracket.It doesnotincludecolumnsfor catenarylighting.the distancebetweenthe centrelineof thepoint of entryof thelanternandtheintendedgroundlevelfor a columnplantedin theground,or the flangeplate,for a columnwith a flangeplateasshownin FigureA.i.FigureA.i Nominalheight334 EBCS',,101995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENTpost-topcolumna straightcolumnwithoutbracketto supportthelantern(post-toplantern)directly.columnwithbracket a columnto supporta lanternor lanterns(side-entrylanterhs)bymeansof one or more bracketswhich are integralwith, ordemou'ntablefrom,thecolumn.FigureA.2 Bracketprojectionbracketprojection horizontaldistancefrom the pointof entryto the lanternto averticallinepassingthroughthecenterof thecrosssectionof thecolumnatthegroundlevelasshownin FigureA.2.'.The shapeof the bracketis not speCified,in this standardtheconnectingpartontheendof apost-topcolumnor of abracketfor securinga lantern. It maybethe endof thecolumnor thebracketitselfor an additionalparthavingthesameor a differentcrosssectionfromthecolumnor bracket.theconnectingpartona columnfor securingaseparatebracket.Itmaybeof thesamesizeoradifferentcrosssectionfromthecolumn.wbracket a componentusedto supporta lanternata definitedistancefromtheaxisof thelowerstraightportionof a single,doubleor multipleformcolumnandintegralwith,or demountablefrom,thecolumn.lanternfixingbracketfixingETHIOPIAN BUILDING CODE STANDARD EBCS-1:0 1'995 335ELECTRICAL INSTALLATION OF BUILDINGSETHIOPIAN BUILDING CODE STANDARDanglebetweentheaxisof thelanternfixingandthehorizontal.openingin a columnbelowgroundfor cableentry.thelengthof acolumnbelowtheintendedgroundlevelasshowninFigureA.3.J!Y'~),,',---,,'Base plateopeningin a columnfor accessto electricalequipment.platebelowgroundlevelfixedto a plantedcolumnsinkinginto thegroundand to help preventthe columnoverturningas showninFigureA.4.336 EBCS-10 1995,FigureA.4 BaseplateFigureA.3 Planting.depthlanternfixing angledoor openingbaseplatecableentryslotplantingdepthflangeplateSECTION 15: INSTALLATION OF LIGHTING EQUIPMENTa platewithanopeningfor cableentry,attachedrigidlyto a columnwhich is surfacemounted,to allowit to be securedto a concretefoundationor otherstructuresasshownin FigureAS.).~.Flange plateFigureA.5 FlangeplateA.2 DIMENSIONS AND TOLERANCEA.2.t RequirementsThe dimensionalrequirementsarespecifiedexceptthattheconnectiondimensionsinClauseA2.7 representa recommendedchoice.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 337ELECTRICAL INSTALLATION OF BUILDINGSA.2.2 Posttopcolumns,maindimensions(in meters)For to.lerancesfor dimensionsandshapeseeclause8!i.1For dimensionsfor dooropeningsandcableentryslotsseeclause A 2,~+..-- -., +.01 J~Nominalhuillhth3...-------.----4--.----_....__ .5------6----810- 12---_.15,_ ...--18.~_. __ _ _ On_ ___20Z-..r W$.I 1 r'....:'Type A1For baseplateseeclause A..?.5Type A2 Type A3For flangeplateseeclause' Al.6For columnfoundationseeclausE' A 2.5338 EBCS-to1995 ETHIOPIAN BUILorNGCODE STANDARDSECTION 15: INSTALLATION OF LIGHTING EQUIPMENTA.2.3 Columnswithbrackets,maindimensions(in meters)wConnection dimensions(seeclause AZ.?)Lantern fixing angle5 or 15Projectionwll0.751,2523Nomine'helohlh56Bto121518For tolerancesfor dimensionsand shape.seeclause A~.8The shapeof the bracketIs not specifiedin this standardFor dimensions for dooropening' and cableentrySlolSseeclauseA;Z.4')0'----0/m~For baseplate~ seeclause A1.5 For flangeplateseeclousa AZ.t:Typo B1 Type B2 Type B3For column foundation seeclause A2.511 II is recommondedIhal w venerallyshouldbeequello.or lessIhln.1-ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 339ELECTRICAL INSTALLATION OF BUILDINGSA.2.4 Dooropeningsandcableentryslots(dimensionsin millimetres)---,50-.-@JIF'Jwe. A23Position of door4) and cable entry slotFl!I~aa1.01- -:~T II '>_,a ........a-9Ull~--~.'),// ~I/' IaUl.-a b2007530085-4001'00._-~---- 500 100500120600115.._----600 1306801)951)6801)1301)- 900') 1301)1=lt'H~A2.'Dimensions of cutout1) Supplementarydimensionsfor concretecolumns.2) For metalcolumnsonly.3) It is recommendedthatthisdimensionbe approximately600mm,but in no caseshallit be lessthan300mm;no maximumis specified.4) It isrecommendedthatthedooropeningispositionedparalleltothebracketonthesideawayfromthedirectionof traffic.340 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 15: INSTALLATION OF L' 3HTING EQUIPMENTA.2.SColumnfoundation,plantingdepthandbaseplate(din .siansin rnillirnetres)300X 300or400x 400+.~tFigure A2.5a FigureNominalPlanting dapthhaight --h e1)m ELECTRICAL INSTALLATION OF BUILDINGSA.2.6 Flangeplate(dimensionsin millimetres)j~t' , I )//.~rd,l1,11Id2min.!M1822400M2430500,M27 33700h csllad,1)mmin.< 52608200M18' 1240010300M24A2.7 ConnectionDimensionsforLanterns(in millimetres)l)Fiuuro A 2.',1dlJ1 '1/tlO70-.---76 130102250d2J1 '2,42100} --60100250-;t(2 )Figure A2~bSECTION 15: INSTALLATION OF LIGHTING EQUiPMENT~lPosttop !;.oternsFigure1) SeeclauseA.2.1.2) This designdoesnot applyto concretecolumns.3) Diametersof steelspigotsshouldbe asgivenin ISO 64-1974'Steeltubes,outsidediameters'for steeltubesof thenearestsize.Figurll AZ.IObSidtl entry lantornsri {,!cu( .. j E+ 'x .-l::: ~'III .~ .' ~II' I Lt. !ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 343SECTION 16FIRE ALARM SYSTEM AND FIRE PUMPS16.1 SCOPE(1) This Sectiondescribesthe essentialsof the fire alarmsystemsandappliesto theinstallationof localfire alarmsystemsandfirepumps.16.2 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationof Buildings.a) BS - CP 1019:1972' The Installationand Servicingof ElectricalFireMarm System.b) C22.1:1990 ~anadianElectricalCode,Part 1,SafetyStandardfor ElectricalInstallations,sixteenthEdition.c) DIN 57833:1982 Danger Alarm Systemsfor Fire, Hold-up andIntrusion,Parts1and2.d) ,Euro Standard,En 54:1976 Componentof theAutomaticFire AlarmSystems,Parts1 and 5.16.3 DEFINITIONS(1) In additionto thetermsdefinedin Section1,thefollowingdefinitionsshallapplyinthisSection:344 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDfire alarmsignal a signalwhichalertsthefire fighting forces.flamedetector a detectorwhichrespondsto theradiationemittedby fire.heatdetector a detectorwhichrespondto an increasein temperature.EBCS-10 1995 345a facilitywhich issuesthe fire alarm- e.g.,by meansof audibleandvisual signallingdevices- andwhich is not containedin thefire alarmcontrolandindictingpanels.a glazed constructionstandingabove the surface of a roof,designedto admit light to the spacebelow.particulateproduct of combustiongeneratedby fire, whetherthis be of smoulderingor open-flametype.devices in which electric signals are converted into soundsignals.SECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPSETHIOPIAN BUILDING CODE STANDARDalarmboxcdntrolroom a facilityfrom whichthenecessaryfire fightingmeasurescanbeinitiatedatall time.automaticfire detector apartof a firealarmsystemwhich,eithercontinuallyor atperiodicintervals,observesasuitablephysicaland/orchemicalidentifierfordetectinga fire in themonitoredarea.smokesounderssmokedetector .a detectorwhich respondsto productsof combustionand/orpyrolysis(suspendedmatter)containedin theair.automaticfire alarmsystem a systemwhich detectstheoccurrenceof fire in its incipientstageandimmediatelysignalsthiswithouthumanintervention.lantern-lightalertingfacilityfire alarmsystem the entiretyof the equipmentand parts, matchedfor correctinteraction,usedin a fire alarmsystem.fire identifiers physicalvariableswhicharesubjectto measurablechangesin theenvironmentof a fire in itsincipientstage;e.g.risein temperature,smoke,flameradiation.ELECTRICAL INSTALLATION OF BUILDINGSfalsealarm a fire alann signal'causedby technicalmalfunctionsin the firealannsystem(alannresultingfromdisturbance)or spuriousalannsresultingfromthefire detectorbeing'mislead'.non-automatic(manual)fire alarmdevices alarmdeviceswhichcanbeusedto initiatethefire alannsignalsmanually.16.4 DESIGN CONSIDERATION16.4.1General16.4.1.1 Design(1) Fire alannsystemsshallbedesignedsothat:a) theearliestpossibledefinitewarningof fire (i.e.,avoidingfalsealann)is givento allpersonnelimmediatelyconcerned;b) it is capableof indicatingthelocalityof theoriginof thefire alannasto facilitatethesafeevacuationof thepremisesandto directfire fighters; andc) it performsits functionwith greatreliability.16.4.1.2 Equipmentandpowersupply(1) The equipment,wiring anduseof thefire alannsystemshallbeexclusiveto thatsystemandits powersupplyshallbeprovidedindependentlyfromthosefor anyotherequipment.16.4.1.3Alarmsignals(1) The audibleandvisualalannsignalsshallbeusedsolelyfor thefire alannpurpose,andthesesignalsshallnot resetautomatically.16.4.1.4 Locationof thealarmcontrolandindicatingpanel(1) The fire alann and associatedindicatingpanelshall be sitedwherethey can be undetconstantobservationwhenthepremisesareoccupiedandshallbeaccommodatedin a room:a) in thedirectvicinityof themainentrance;346 EBCS40 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPSb) that providesadequateprotectionagainstambientinfluenceswhich could impairoperations;e.g.vibration,smoke,dust,gasses,vapour,etc.producedby ma.chinery,etc;andc) that has room climatesuitablefor properoperationof the fire alarm control andindicatingpanel.16.4.1.5Explosiveorflammableatmosphere(1) If it is necessaryto installthefire alarmequipmentor wiring in situationwhereJhere maybe an explosiveor flammableatmosphere,the applicableClausesof Section 12 shall beobserved.16.4.2 Circuit Design16.4.2.1 General(1) Thedesignof a fire alarmcircuitshallprovidefacilitiesfor rapidandreliabletransmissionof initiatedsignalswhenmanualcall pointsor detectorsareoperatedandwhenspecifiedfaultsoccurto controlandindicatingequipment.16.4.2.2Numberof circuitelements(1) For sakeof reliability,thenumberof circuitelementsin thefire alarmsystemon whichalarmactuationdependshallbekeptto a minimum.16.4.2.3 Transmissioncircuitry(1) Any resultantsignalshallbetransmittedby thesimplestpossiblecircuitryto soundersandotherindicatingequipmentandto any equipmentwhich is to be operatedby the fire alarmsystem;e,g.fire extinguishers,fire protectiontraps,localplantfacilities,etc.16.4.2.4 Faultsignaldiscrimination(1) Wherechancesof malfunctionarehighin a fire alarmsystem,discriminatorycircuitshallbe incorporatedin thesystemsothatfalsealarmsareidentified.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 347ELECTRICAL INSTALLATION OF BUILDINGS16.4.2.5 Originof callindication(1) Except in buildingswherefire canbe locatedwithoutdelay,thefire alarmsystemshallincludean indicationpaneldesignedto showclearlythelocationof theorigin of thealatm.Note: To meetthisrequirement,suitablezonesshouldbedefmedthroughoutthebuildingsothatall thedetectorsand/ormanualcallpointsinanyonezoneareconnectedtoanindicatorexclusiveto thatzone.16.4.3 ManualCallPoints16.4.3.1 General(1) A manual call point shall be operatedby a spring-loadedswitch w~ich is held in'non-alarm'positionand protectedfrom accidentaloperationby a coverusuallyof glass.Breakingthis glasscoverreleasesthe switchto an 'alarm'positionandthe systemstartstooperate.'1li :16.4.3.2 Constructionandrequirements(1) Manualcall pointsshall:a) beconstructedof pressedmetal,castmetal,or plasticmaterialssothattheywill notbeadverselyaffected'by theambienttemperature;b) be rigid enoughin constructionto withstandtheabuseto which theyare likely to besubjected,withoutdeteriorationor reductionin theirabilitytooperateeffectivelywhenrequiredto do so;c) havecontactsthatarecapableof operatingsatisfactorilyduringthedesignlife of theinstallation;d) becoloured'signalred'overat least50%of theirvisiblearea;e) havereplaceableglasscover;breakingthe glassshallautomaticallyoperatethe callpoint,andshallincludedescription'ofthemethodof operation'by aconciseinscription It is recognizedthattherearesituations,e.g.foodprocessingareas,wherethistypeof callpointisunacceptableandtheremaybenoalternativetousingasuitablemanualcallpointofthetoggle-switchtypewithsafeguardsagainstaccidentaloperation.The methodof operationin an installationshouldbeidenticalunlessthereis specialreasonforvariation.348 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPSincludingtheword 'FIRE' on case,or by a suitablyinscribedplatebehindtheglasscover;andf) incorporatemeanswherebysatisfactoryoperationmaybereadilyandindividuallytested;e.g.by openingthefrontby meansof a specialkey.16.4.3.3Stricker(1) A strikershallbeprovidedadjacentto thecall pointto facilitatebreakingtheglass.16.4.3.4Placement(1) Manualcall pointsshallbe:a) so locatedthatno personneedtravelmorethan30.0mfrom anypositionwithin thepremisesin orderto givefire alarm;.b) locatedon theexit routesand,in particular,on thefloor landingof staircasesandonexitsto thestreet;and~c) fixed at a heightof 104m abovethe floor at easily.accessible,well illuminatedandconspicuouspositionsfreefromobstruction.16.4.3.5Manualcall in automaticalarm(1) Wheremanualcall pointsareincorporatedin anautomaticfire alarmsystem,theyshallbeincludedin sucha way thattheoperationqf anyone of themproducesthe sameeffectsasthoughfire hadbeendetectedby a fire detectorin thesamezone.16.4.4 Selectionof Fire Detectors16.4.4.1 General(1) Whenselectingthetypeof detectors,theprobabledevelopmentof fire in theincipientstage,theroomheight,theambientconditionsandall sourcesof spuriousalarmsin theareasto bemonitoredshallbetakenintoconsideration.Note: The taskof fire detectorsis to detecta fire whereverpossiblein its incipientstageandsignalthisautomaticallyto anemergencyservice.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 349ELECTRICAL INSTALLAT1ON OF BUILDlNGS16.4.4.2Detectortypes(1) If developmentof a smoldeJ;ingfire is anticipatedin the incipientstageof fire (intensesmokegeneration,very littleor no flameradiation),smokedetectorsshallbe.used.(2) If a rapiddevelopmentof thefire is anticipatedas earlyas in the incipientstageof a fire(intenseheatgeneration,intenseflameradiation,andgenerationof smoke),smokedetectors,heatdetectors,flamedetectors,or combinationsof thevarioustypesof fire detectorsshallbeused.Note: Thefactisthatcombustionisnotalwaysaccompaniedbyflameandthereflectedradiationeffectrestrictstheapplicationof flamedetectors.(3) Jf smokedamageis anticipatedas earlyas the incipientstageof a fire owing to )'oomoccupancy(risk to humanlife, materialsandgoodssensitiveto smoke),smokedetectorsshallbeused.(4) If averyrapiddevelopmentof thefire is anticipatedwith a highdegreeof probability,anautomaticextinguishersystemshallbeconsidered.(5) If it is not possibleto predictor anticipatethedevelopmentof a fire in the alarmar~~specialinvestigationshallbeconductedto assistin selectingtheparticulartypeof requiredfirealarmdetectors.16.4.5 SittingofDetectors16.4.5.1Monitoring(1) Building andinstallationcomplexesshallbe monitoredor coveredcompletelyandeacheffectivelyenclosedspaceshallbeconsideredseparatelyfor thispurposein accordancewiththelimits of spacingfor thetypesof detectorsconcerned.Notes: i) If, for somereasona fIrealarmsystemis notinstalledthroughouta buildingor a relatedseriesofbuildings,thecriterionshallbethatthesystemwill coverallof anareahavingphysicalboundariesofsucha natureastoprovideadequatefIreseparationorall of anareasurroundedby sufficientopenspace;e.g.roads,to provideadequatefIreseparation.ii) Voidsnotmorethan800.0mmin heightneednotnecessarilyhaveindependentmonitoring.Hi) Smalllavatoriesandwaterclosetsneednothaveindependentmonitoringbut;mayrelyuponthatprovidedin a lobbycommonthereto.350 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS16.4.5.2 Sectionedrooms(1) Roomsdividedintosectionsby walls,partitionsor storageracksreaching300.0mmof theceilingor wheregoodsmightbestackedin definedareasto a correspondingheight,shallhavedetectorsfor eachsectionor passageway.16.4.5.3 Flue-likeopenings(1) Hoists,elevatorsandsimilarflue-likeopeningsshallbemonitoredby detectorsatthetop.16.4.5.4 Staircases(1) Staircasesshallbemonitoredby detectorson eachfloor.16.4.5.5 Lanternlights(1) Lanternlightsshallbemonitoredby detectors.16.4.5.6 Specialmonitoring(l) Due to therequirementsof theuseto whichanyroom,space,areaor void is to beputorto its structuralfeatures,installationof additionaldetectorsshallbeconsidered.16.4.5.7 Heightconsideration(1) Generally,theinter-relationshipbetweenthesuitabilityof thevarioustypesof firedetectorsandroomheightindicatedin Table 16.1shallbeobserved.16.4.6 Sittingof HeatSensitive(point)Detectors16.4.6.1 Positionrelativetoceiling(1) Heat sensitivepoint detectorsshallbe mountedso thattheir heatsensitiveelementsarepositionednotlessthan25.0mmandnotmorethanl50.0mmbelowtheceilingortheundersideof theroof.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 351ELECTRICAL INSTALLATION OF BUILDINGSTable16.1Suitabilityof d'etectorsandroomheightHeat detectors..SmokeRoom heightdetectorFlame. Cat. 1Cat.Cat. 3detectorss 2Upto 20.0mWWWW RUpto 12.0mRWWW RUpto 7.5mRRWW RUpto 6.0mRRRw RUpto 4.5mRRRR RR ' Suitable16.4.6.2Limits of spacingw-= Unsuitable I(1) ThespacinglimitsindicatedonTable16.2shallbeobservedin sittingdetectors.(2) Notwithstandingtherequirementin (1) above,themaximumspacingbetweendetectorscannotapplyin all directionssincethearealimitshallbeobserved,butdetectorsshallnotbemountedcloserthan500.0mmtoanyoutsidewalls,separatingwallsordividingpartitions.Table16.2Spacinglimitsfor sittingdetectorsMaximum (horizontal) distanceMaximum floorMaximum (horizontal) dlatancefrom any outside walls,area to be coveredapart between centers [m]separating walls or dividingby one detectorpartitions [m][m2] In generalIn corridorsIn generalIn corri.dors50.010.015.03.57.5 In specialbuildingssuchaschurcheli,mosques,museumsandcastles,itmaybethatdetectorscanonlybearrangedatagreatheightunpercertaincircumstances.Thiswillmeanthatanearlyfirewarningcannotbeguaranteed.This rendertheuseof thefirealarmlessworthwhile. Detectorsaresub-dividedintothreeresponsecategoriesin linewiththedifferingceilingheights.Sensitivedetectors(e.g.detectorsof responsecategory1)maybeusedfor highceiling.352 EBCS-tO 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS16.4.6.3 Ceiling(1) Whereceilingsarecrossedby beams,girdersor otherstructuralfeatureshavinga depthof500.0mmor more,atleastonedetectorshallbeinstalledin each'pocket'fonnedbetweensuchfeatures,andthesedetectorsshallnotbe lessthan500.0mmfromanybeam,guideror wall.16.4.6.4Singletrussandnorth-lightroofs(1) Onerow of detectorsshallbesitedalongtheapexof eachroof orbay;theseandanyfurtherdetectorsneededto covertheareashallbespacedin accordancewith 16.4.6.2.16.4.6.5Floo,'openings(1) Detectorsshallbeso sitedthatatleastoneon eachfloor is suitablyplacedwithin 105mofhoists,elevators,stairways,well-holes,andsimilaropeningsto thefloor above.16.4.6.6 Lanternlights(1) Detectorsfittedin lanternlightsshallbeprotectedfromdirectsunlight;fixed-ternperature-'.typedetectorsshallbeusedin suchlocation.Note: Suchlocationsareliabletorapidtemperaturevariationsduetocombin/ltionof solarandinternalheatingand,thus, ftxed-temperatere-typedetectorsarerecommended.16.4.6.7Ambienttemperature(1) Wherehighand/orsuddenlyrisingtemperatureowningtonaturalconditionsor conditionsresultingfrom nonnaloperationarelikely, fixed-temperaturedetectorsshallbeused.(2) The staticresponsetemperatureof thedetectorsectionshall lie betweenlOoeand 35Cabov.ethe maximumtemperaturewhich can occur in the vicinity of the detector;and themaximumtemperaturesettingshallnotexceed88e.16.4.7 VibrationCombinedwithRapidTemperatureChange(1) If detectorshaveto befittedwheretheywill besubjectto shockand/orvibrationandmayalsoexperiencerapidtemperaturechanges(e.g.,in coveringhoistapertures),a fusiblealloyfixeQ.-temperature-typeshallbeused.Note: Vibrationcoincidingwithrising,althoughnotdangerouslyrising,temperaturecouldinducefalsealannsfromothertypes.ETHIOPIAN BUILD1NG CODE STANDARD EBCS-101995353ELECTRICAL INSTALLATION OF BUILDINGS16.4.8 Sittingof Heat-Sensitive(Line)Detectors(1) Thesedetectorsare affectedby the samephenomenonas the point detectors,and therecommendationsgivenin Clause16.4.6shallbecompliedwith.16.4.9 Sittingof Smoke-SensitiveDetectors16.4.9.1 General(1) Smokedetectorsshallnormallybesittedatthehighestpartsof theenclosedareas,andshallbemountedsothattheirsensingareais notlessthan25.0mmor morethan600.Ommbelowroofceiling,exceptasmaybe indicatedby sitetests.16.4.9.2 Heatbarrier(1) The sittingof smokedetectorsshallbearrangedto taketheeffectsof heatbarrier.Note: Wann air naturallycollec~ underceilingandin theapicesof pitchedroofs.. In somecircumstances,thiswann aircanformwhatis usuallyknownasheatbarrierto theproductsof combustionrisingfrom firewhichis producinglittle changein theambientcondition.The combustionproductsfromsucha fire will spreadoutbelow theheatbarrierin thesameway astheydo beneatha ceiling or an apexof pitchedroof.16.4.9.3 Otherfactors(1) Factors affectingthe sitting,number,etc. of the smokedetectorsshall be consideredcarefullyandthenecessarymeasuresshalLbetaken.Note: Among factswhich canestablishtemporaryor permanentconditionswhichhavetheireffectonthesittingof smokedetectorsarevariousformsof overheadheating,air-cooledequipment,roof or ceilingof unusualshape,lofty buildings,staircases,canteenandrestaurant,plantrooms,ambientair currents.16.4~10AudibleandVisualAlarms16.4.10.1General(1) Insidea building,at leasttwo soundersshallbe installed.(2) In caseof anautomaticsystem,anadditionalsounderoutsidethebuilding(preferablynearfive brigadesaccess)shallbe installed.354 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS16.4.10.2 Audibilityofgeneralalarm(1)'Alarmsoundersshallsatisfythefollowingrequinnents:a) Their type,numberandlocationshallbe suchthatthealarmis distinctfromthebackgroundnoisein everypartof thepremises.b) Theirnoiseshallbequitedistinctfromanyothersounderslikelytobeheard.c) Alarmsoundersof thesamekindona particularinstallationshallproducea similarsound.16.4.10.3 Restrictedalarms(1) Wherea generalalarmis undesirable(e.g.departmentstores,entertainmentplaces,hospitals),thealarmsystemshallberestrictedtotheprovisionof soundersoutof thehearingof thepublicorpatients.(2) Thesoundersshouldbesupplementedbyanadequatenumberof visualsignalsthroughoutthepremisesfor staffrecognitiononlyand/orbydiscretespecialalertingfacilities.16.4.10.4 Silencingswitch(1) Silencingswitchesshallonlybeinstalledfor transferringanalarmor faultwarningto asupervisorysounders,andshallbesoarrangedastoputoutof servicethesmallestpracticablenumberof manualcallpointsanddetectors.(2) Theoperationof asilencingswitchshallneithercanceltheindicationsofthealarmorfaultonanyindicatorconcernedwhileanalarmor faultconditionexistsnorpreventtheproperreceiptof alarmsor faultwarningsonanycircuitotherthanthosewithwhichthesilencingswitchis associated.16.4.10.5 Two-stageala,.',(1) Whereit isdesiredtodistinguishbetweenanalertandanevacuatesignal,atwo-stagealannshallbeusedin whichthefirsttypeof signalindicatesanalertandthesecondtypeindicatesaneedtoevacuatethelocality.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 355ELECTRICAL INSTALLATION OF BUILDINGS16.4.10.6Visualalarmsignals(1) In general,visualsignalsshallbeusedto supplementaudiblealarms.(2) The operationof a soundershall not be preventedby a defectin a visual signal orvice versa.(3) In situationswherea normaltypeof alarmsoundermay be ineffective,e.g. wherethebackgroundnoiseis excessiveor wheretheoccupantsaredeaf,visualsignalssuchasrotatingbeaconlampsshallbeusedin addition.16.4.10.7Audiblealarmsprovidedbypublicaddressequipment(1) Where public~address.equipmentis usedin steadof co~ntional sounders,it shall beens.uredthat:a) alarmof fire is automaticallytransmittedoverthepublicaddr~sssystem,takingpriorityandover-ridingeveryotherfacilityandcircuitconditionsof thepublicaddresssystem;b) othersignalssuchmeal-break,startandstopwork,arenotatanytimebroadcastbythepublicaddressequipmentin a mannerwhichcanbeconfusedwith a fire alarmsignals;c) duringalarmconditions,all microphonesareautomaticallydisconnected,exceptonedesignateda 'fire microphone'which is retainedin circuitso that it can be usedforannouncementsandinstructionsrelatingto thefire;d) thepowersupply,cablingandwiringof thesystemshaHcomplywiththerequirementsof this Section.16.5 CABLESANDWIRING16.5.1 Cables16.5.1.1 General(1) Cablesshallhavecopperconductorsandthecross-sectionalareaof theconductorsshallbeselectedon thebasisof thecurrentconsumptionof theequipmentusedandthe line length.16.5.1.2 Insulationresistance(1) The insulationresistanceof the individualcablewith respectto earthshall at leastbe400.0Kohm.356 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD(1) Cablesshallbe suitablefor thepurposeof thetypelistedin AnnexB of Section4.(1) Conductorsinstalledin buildingsof combustibleconstructionshallbepermittedto be:-SECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPSEBCS-10 1995 357a) non-metallicsheathedcable;orb) fire alarmandsignalcable.16.5.1.3 Conductorscrosssectiona) installedin a Q1etalracewayof thetotallyenclosedtype;b) incorporatedin cable,havingmetalarmQuror sheath;c) installedin rigid non-metallicconduitwhereembeddedin atleast50.0mmof mansonaryor pouredconcrete,or installedunderground.a) 1.5mm2for individualcablespulledintoraceway;b) O.8mm2for individualcableslaid intoraceway;c) O.8mm2for an integralassemblyof two or morecables;d) O.5mm2for an integralassemblyof four or morecables.(1) Conductorsshallnotbesmallerthan:16.5.1.4Suitability(2) Notwithstandingthe requirementsin (I) above,cablessmallerthan2.5mm2 installedinracewayshallbeequipment-wiretype.16.5.2 Wiring Method16.5.2.1 Installation(1) All conductorsof a fire alarmsystemshallbt;~.16.5.2.2 Conductorin buildingof combustibleconstructionETHIOPIAN BUILDING CODE STANDARDELECTRICAL INSTALLATION OF BUILDINGS16.5.2.3 Segregation(1) The conductorsshallbe installedso asto beentirelyexclusiveto a fire alarminstallationandthewiringof thealarmsystemshallbesegregatedfromthewiringof anyothercircuitsandshallnotentera fixture,raceway,boxor enclosureoccupiedby otherwiring,exceptasmaybenecessaryfor connectionto:a) thesourceof supply,b) a signal,c) anancillarydevice,d) a communicationcircuit.16.5.2.4 Spacingandcrossing(1) Fire-alarmwiring shall be spacedat least50.0mmawayfrom the circuitsof any otherservice.(2) Notwithstandingtherequirementsin (1) above,wherecrossingsareunavoidable,a bridge-of suitablenon-combustibleinsulatingmaterial,at least6.0mmthick,shallbesecurelyfittedtomaintainpathin air of 50.0mmbetweencircuits.16.5.2.5Highestvoltage(1) All conductorscontainedin the samerl},cewayor cableshallbe insulatedfor thehighestvoltagein theracewayor cable.16.5.2.6Avoidanceofflue-likeopening(1) In orderto reducethe likelihoodof damageto fire-alarmcablesby fire, mainfire alannwiring shallavoidlift wells,staircase,andotherflue-likeopening.16.5.2.7 Disruptiveelectricalinfluences(1) If necessary,specialmeasuresshall be takento protectthe fire-alarmnetworksagainstdisruptiveelectricalinfluences(electricalinterferences)resultingfromlightningstrike,switchingon high-powerloads,electricalsparksof all typesandelectromagneticwaves.358 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS16.5.2.8 Connectionpoint(1) The numberof connectionpointsshallbeasfew aspossible.(2) Any necessaryconnectionpointmustbesolderedor establishedusinganotherveryreliablemechanicalmethod.16:6 EQUIPMENT BONDING16.6.1ExposedNon-CurrentCarryingMetalPart(1) Exposednon-current-carryingmetalpartsof electricalequipment,includingoutletboxes,conductors,raceway,andcabinets,shallbebondedto earthin accordancewith Section7.16.6.2BondingConductor(1) Wherea non-metallicwiring systemis used,a bondingconductorshallbe incorporatedineachcableandshallbe sizedin accordancewith applicableClausesof Section7.16.7 POWER SUPPLY SYSTEM16.7.1OperatingVoltage(1) The operatingvoltageof a fire alarmsystemshallnot exceed230.0Vnominalwhetherbetweenconductorsorto earth.16.7.2Sourcesof Power(1) Two mutually independentpower sourcesshall be providedfor poweringa fire alarmsystem.The sourcesshallbe:a) a generalmainsor anequivalentnetwork,operatedcontinually;andb) a rechargeablebatterywhichis abletopowerthefire alarmsystemwithno interruptionin theeventsof a main'sfailure.,(2) The powersourcesshallbepermanentlyconnectedto thefire alarmsystemandit shallbeensuredthatfailureof onepowersourcedoesnot resultin failureof theotherpowersource.Notes: i) Onlybatteriesthataresuitablefor stationaryoperationandtrickle-chargingmustbeused.ii) Wherenomainssupplyis available,a primarybatterymaybeusedforpowt:ringfirealarmsystemsprovidedthata secondsimilarbatteryin operationalconditionis heldin reserveatall times.ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 359,)ELECTRICAL INSTALLATION OF BUILDINGS16.7.3 CurrentSupply16.7.3.1 General(1) The powersupplyfrom theelectricalmainsshall:a) bedimensionedsuchthatunrestrictedbperationof thesystemandthealteringfacilitiesis guaranteed;andb) alsobe ableto supplythetricklechargecurrentfor thebatterywhenthesystemis innormaloperatingcondition.16.7.3.2Circuitconnection(1) A fire-alarmsystemshall be suppliedby its own separatecircuit connectedas closeaspracticable(withoutviolatingotherClausesof thisCode)to:a) the loadterminalson themainservicedisconnect;'b) the secondaryterminalof thetransformer,wheretransformeris necessaryin orderto supplya utilizati0nvoltagerequiredby thefire alarmsystem;orc) theterminalsof a transferswitch,while a fire alarmsystemreceivesemergencypower, from anemergencypowersourcewhichalsosupplyotherelectricalequipment.'16.7.3.3 Fusing(1) A firealarm'sseparatecircuitshallbeprovidedwith itsspeciallymarkedovercurrentdeviceand disconnectingmeanswhich shall be clearly identifiedin a permanent,conspicuousandlegiblemannerasa fire alarmsystem;andthedisconnectingmeansshallbecolouredred andlockablein the'ON' position.16.7.3.4 Chargingfacility(1) The chargingfacility shallbedimensionedsuchthatit if capableof recharginga battery,thechargestateof whichhasdroppedtothecut-offvoltage,automaticallyto80%of itsnominalvoltagewithin a maximumperiodof 24 hours.360 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS16.7.3.5 Interruption(1) Thereshallbeno possibilityof thefire alarmsystempowersupplybeing'interruptedasaresultof otherplantfacilitiesbeingswitchedoff.16.8 FIRE PUMPS16.8.1Conductors(1) Conductorsshallbeof copperandshallhavetheirampacityin accordancewith Section4andtherequirementsof thepumpmotor.16.8.2Wiring Method(1) All conductorsof thefire pumpequipmentshallbe:a) installedin a metalracewayof thet~tallyenclosedtype;b) incorporatedin metalracewayof thetotallyenclosedtype;orc) incorporatedin a cable,havinga metalarmoursheathof a typelistedin Annex B ofSection4.16.8.3 Consumers'Servicefor Fire Pumps16.8.3.1Box(1) Wherefire-pumpequipmentisconnectedtoaconsumers'service,aseparateboxfor thefirepumpequipmentshallbepermitted.16.8.3.2Remotelocation(1) A servicebox for thefire pumpequipmentshallbepermittedto be locatedremotefromotherservicebox.16.8.3.3Labelling(1) A servicebox for fire pumpequipmentshall be labelledin a conspicuous,legible,andpermanentmannerwith the letter'FIRE PUMP'.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 199 361ELECTRICAL INSTALLATION OF BUILDINGS16.8.4 Protection16.8.4.1 Overcurrentprotection(1) The ratingor settingof theover-currentprotectionfor feedersandbranchcircuitsshallbepermittedto be selectedto carrylocked-rotorcurrentof themotor(s)plustheratedcurrentofassociatedequipmenton thecircuit.Note: Wherethelocked-rotorcurrentisnotmarkedonamotor,600%oftheratedcurrentshallbeconsideredtobethelocked-rotorcurrent.16.8.4.2 Shortcircuitprotection(1) The instantaneousshortcircuitcharacteristicshallbepermittedto be selectedor setat aminimumof thenormalloadcurrentof theassociatedequipmenton thecircuitplus 12timesthefull loadcurrentof themotor(s).16.8.4.3 Overloadandoverheatingprotection(1) Thebranchcircuitconductorsandcontrolconductorsor equ~pmentof a fire pumpshaUnotrequireoverloador overheatingprotectionandshallbepermittedto beprotectedby themotorbranch-circuitover-currentdevice(s).16.8.4.4 Earth-/aultcircuitinterrupter(1) Earth-faultprotectionshallnotbe installedin a fire pumpcircuit.362 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDEBCS-10 1995 363'lilT '1IlIn''''H1i' '8'8'8'8'....'onon~.2nd Floor 'if''~.~I~,~.,st Floorg>---'ij'8'8'HHl~ r:..,.'MVIVIV, ,,'o...t-' ...,.....'8'I~/////~.'Cell.'FigureA.l Exampl.e- AutomaticfirealarmsystemII'joIN'ANNEX A (INFORMATIVE)ETHIOPIAN BUILDING CODE STANDARDFigureA.2 Example - Automaticfire alarmsystemswith non-automaticfire alarmdeviceFIRE ALARM SYSTEMS PRACTICAL EXAMPLESDesignations1/1 : 1stdigit - detectorandalarmdevicegroup2nddigit - detectoror alarmdevicenumberin thedetectorandalarmdevicegroupFAP : Fire alarmcontrolandindicatingpanelTS : Transmissionunit for fire alarmsignalsELECTRICAL !NSTALLATION OF BUILDINGSJl4 liSIII ..,ll~Jll f, 1I1Jl12ll/ll0rI4/1 (j.il)111ANNEX B (INFORMATIVE)UIT DESIGNB.l MANUAL ~~DAUTOMATIC CAIJL POINT CIRCUITSB.1.1 IntroductionWhilst therearebuttwo basiccall pointcontrolcircuits,i.e. 'opencircuit' and'closedcircuit',simpledefinitionof eachcanbemisleadingbecause,in practice,thereareemployednumerousvariationsandcombinationsof eachcircuit.The typeof Circuitto be usedshouldbedeterminedby carefulconsiderationof thefunctionsrequiredfrom the fire alarmsystemin theparticularbuildingconcerned,takinginto accountsimplicity,reliability,liabilityto damage,operationalsupervision,cost,environmentandsuchotherrelevantfactors. It is unwiseto assume,in general,thatonetypeof circuitis betterthl:!nanother.Four simplifiedbut typical,circuitsaregivenbelow. Alarm andfault-sensingunitsmayberelays,solid-statecircuitsor similardevices;call pointsmayhavemechanicalcontacts,solid-statecircuits,variable-resistancedevices,etc. It shouldbeappreciatedthatmanyothercircuitarrangementsarepossibleandthefollowingcircuitsshouldin no waybeconsideredotherthanfor thepurposeof illustration.1Open Circuit Call PointB.1.2CircuitI _ Opencircu~ Alarm-sensingunito. 0 supply ItFigureB.I OpencircuitETHIOPIAN BUILDING CODE STANDARD EBCS-101995 365ELECTRICAL INSTALLATION OF BUILDINGSCurrentflowswhenthecall pointcontactsareclosed,causingthealarm-sensingunitto operateandinitiateanalarmsignal.A brokenconnection/conductorwill preventa call pointbeyondthebreakfrom operatingthealarm-sensingunit.A short-circuitbetweenconductorswill causethealarm-sensingunit to operate,producinganalarmsignal.In thiscircuit,thealarm-sensingunitcouldbethealarmsounder.B.1.3 Circuit 2 - ClosedcircuitAlarm-Sensing UnitsupplyoClosed circuit call pointFigureB. 2 ClosedcircuitCurrentis n?rmallyflowing throughthecond~ctorsandcall points;thealarm-sensingunit ishandoperated.Whena call point'scontactsareopened,thecurrentis interruptedallowingthealarm-sensingunit to releaseandinitiateanalarmsignal.A brokenconnection/conductori!1terruptsthecurrentto thealarm-sensingunit, initiatinganalarmsignal.366 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPS-----------------.--------------------.-------------------------A short-circuitbetweenconductorswill allow thecurrentto by-passcall pointsbeyondtheshort-circuit;thus,acall pointbeyondtheshort-circuitcannotinterruptthecurrentandcannot,therefore,initiateanalarmsignal.B.1.4 Circuit3 - Combinationof openandclosedcircuits,TypeAFigureB.3 Combinationof openandclosedcircuits,TypeALow-current ~Open circuit call pointsensing unit (fault)supplyO---------lHigh-current Limiting resistor' .Sensing Unit(alarm)Opencircuitcall pointsareconnectedacrosstheconductors.Operationof a call pointallowsthecurrentto by~passtheresistor.The resultantincreasein currentoperatingthehigh-current(alarm)sensingunit whichinitiatesanalarmsignal.The conductorsareclosed-circuitconnected;aresistorlimitsthecurrentthroughtwo sensingunitsto a valuesufficientto holdoperatedthelow-current(faults)sensingunit,but insufficientto operatethehigh-current(alarm)sensingunit.A broken connection/conductorwill interruptthe current,releasingthe low-current(fault)sensingunit-which initiatesa faultsignal.A short-circuitbetweenconductorsby-passesthe resistor,the resultantincreasein currentoperatesthehigh-current(alarm)sensingunit,whichinitiatesanalarmsignal.//ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 367B.l.S Circuit -I - Combinationopenandclosedcircuits,TypeBLimitingresistor1 / -~~;;i~~~High-current sensing Open circuitSupply unit (fault) ~ call point .O----------~LoW_o'rr.n' '.n'~'l ,nin, r .. i::::unit (fault) ----~- '_._M__ ' . _Medium-current Open circuitSensing unit (al~ call pointo 0FigureB.4 Combinationopenandclosedcircuits,TypeBThe conductorsare'closedcircuit'connected,theopen-circuitcallpointsbeingwiredin series,their contactsbeingbridgedby resistors. The valuesof the call point resistorsand of thelimitingresistorarecarefullychosentoensurethatthecorrectcurrentflows inthecircuitduringthevariousconditionsof faultandalarm.Undernormalconditions,thecurrentflowingin thecircuitis sufficientto holdthelow-current(fault) sensingunit operational,but is insufficientto operateeitherthemedium-or thehigh-currentalarmor fault-sensingunits.Operationof a call pointby-passesits call pointresistor. The resultantincreasein currentissufficientto operatethemedium-currentalarm-sensingunit,whichinitiatesanalarmsignal,butis insufficientto operatethehigh-currentfault-sensingunit.A brokenconnection/conductorwill interruptthecurrent,releasingthelow-currentfault-sensingunitwhich initiatesa faultsignal.A short-circuitbetweenconductorsby-passesthe limitingresistor. The resultantincreaseincurrentis sufficientto operateboththemedium-currentalarmandthehigh-currentfault-sensingunits. The former'sattemptto initiateanalarmsignalis overriddenby the latteranda faultsignalis initiated.Studyof the abovecircuitswill indicatethateachcircuithasadvantagesanddisadvantages.Someof theseareoutlinedin ClauseB.2.368 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 16: FIRE ALARM SYSTEM AND FIRE PUMPSB.2 ADV ANTAGESANDDISADV ANTAGESOFV ARIOUSCALLPOINT CIRCUITSb.2.! Circuit 1a) Advantagesi) This is a simpleandreliablecircuit.ii) No currentis consumedon stand-by;therefore,a batteryandchargerof moderatesizeandcostmaybeused.iii) A brokenconnectionor conductorwill notresultin a falsealarm.b) Disadvantagesi) Therewill beno indicationof a breakin thecircuitwhichmaymakesomepartsofthesysteminoperative.ii) A short-circuitbetweenconductorswill producea falsealarm.iii) The call pointsarenotmonitored.B.2.2 Circuit:2a) Advantagesi) This is a simpleandreliablecircuit.ii) The call pointsaremonitored.iii) The contactsandconnectionsaremonitored.b) Disadvantagesi) Currentis consumedon stand-by;therefore,the sizeandcostof thebatteryandchargerwill be increased.ii) Therewill beno indicationof a short-circuitbetweenconductorswhichmaymakesomepartsof thesysteminoperative.iii) A brokenconnectionor conductorwill causefalsealarm.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 369ELECTRICAL INSTALLATION OF BUILDINGSB.2.3 Circuit 3 TypeAa) Advantagesi) The conductorsaremonitored.ii) An opencircuitof aconnectionor aconductorwill produceafault signal;nota falsealarm.b) Disadvantagesi) Currentis consumedon stand-by.ii) A shortcircuitbetweenconductorswill causea falsealarm.iii) The call pointsarenotmonitored.B.2.4 Circuit 4 TypeBa) Advantagesi) Theconductorsaremonitored.ii) An opencircuitof a connectionor a conductorwill produceafault signal,not afalsealarm.Hi) A short-circuitbetweenconductorswill produceafault s~gnal,nota falsealarm.b) Disadvantagesi) Currentis consumedon stand-by.ii) The selectionof valuesof call-pointresistorsand limitingresistorsis critical.Anumberof call pointsoperatedtogethermayresultin a fault signalinsteadof analarmsignaLiii) Thereis a needfor introductionof additionalandcomplexsensingequipment.310 EBGS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 17SIGNS AND OUTLINE LIGHTING17.1 SCOPE(1) This provisionsof thisSectionapplytotheinstallationof signsandoutlinelightingwhereinthesourceof lightare:a) incandescentlamps,b) fluorescentlamps,c) high-voltageluminousdischargetubesincludingneontubes,andd) high intensitydischargelamps.Note: The word 'sign',whenusedthroughoutthis Section,includesthoseof thethrough-walltype.17.2 NORMATI%REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.The Instituteof Electrical Engineers,Regulationfor the ElectricalEquipmentof Buildings, FourteenthEdition (1966), IncorporatingAmendments.a) IEE:1970b) C22,1:1990 CanadianElectrical Code, Part 1, Safety Standardfor ElectricalInstallation,SixteenthEdition17.3 GENERAL REQUIREMENTS17.3.1 Construction(1) All signsandoutlinelightingapparatus,accessories,andfittingsmanufacturedwholly orin partin thefield shallcomplywith therelevantrequirementsof:ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 371ELECTRICAL INSTALLATION OF BUILDINGSa) thisCode;andb) theapplicableinternationalstandards,if any,exceptsofar astheserequirementsmaybemodifiedby thisCode.17.3.2 DisconnectingMeans(1) Eachoutlinelightinginstallationandeachsignotherthantheportabletypeshallbeprovidedwith a disconnectingmeanswhichshall:a) openall unearthedconductors;b) besuitablefor conditionof installationsuchasexposureto weather;andc) be integralwith thesignor outlinelighting.17.3.3 Rating of DisconnectingMeans and Control Devices(1) Switches,flashers,andsimilardevicesbreakinginductiveloadsshallbe eitherof a typeapprovedfor thepurposeor haveacurrentratingof not lessthantwicethecurrentratingof theloads.17.3.4 Thermal Protection(1) Ballastsof thethermally-protectedtypeshallberequiredfor all signsandoutlinelightingwhichemployfluorescentlampsexceptwheretheballastsareof thesimplereactancetype.17.3.5 Branch Circuit Capacity(1) Circuitsshallbearrangedsothattheloadimposedby lampsandassociatedgearsshallnotexceed80%of thebranchcircuitovercurrentprotection.17.3.6 Location(1) Signsandoutlinelightingshallbe locatedsothatall thefollowingrequirementaremet:a) Any personworkingthereonis notlikelytocomeintocontactwithoverheadconductors.b) No partof thesignor itssupportwill interferewithnormalwork operationsperformedon electricalandcommunicationutility lines.c) No partof the signor its supportis in suchproximityto overheadconductorsas toconstitutea hazard.372 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 17: SIGNS AND OUTLINE LIGHTINGd) Unlessmechanicalprotectionis providedto preventpersonsor vehiclesfrom cominginto contactwith theelectricalcomponentsof thesign,no partof thesign,otherthanits support,shallbe locatedwithin2.2mabovegrade.17.3.7 Bonding(1) All conductivenon-current-carryingpartsof thelightinginstallationshallbebondedtoearthin accordancewiththerequirementsof Section7 exceptfor conductivepartsof lettersattachedto thebuildingandilluminatedfromtherear.17.3.8Protection of Sign Leads(1) Signleadswhichpassthroughthewallsor partitionsof thesignstructureshallbeprotectedby non-combustible,moisture-absorptionresistingbushings.17.3.9 Installation of Conductors(1) Conductorsfor sign and outlying lighting shall be installedin accordancewith therequirementof Section8.17.3.10Fuseholdersand Flashers(1) Fuseholder,flashers,etc. shall be enclosedin metalandshall-beaccessiblewithoutthenecessityof removingobstructionsor, otherwise,dismantlingthesign.17.4 HIGH-VOLTAGE LUMINOUS DISCHARGE TUBE SIGNSAND OUTLINE LIGHTING17.4.1 Enclosure17.4.1.1 General(1) Enclosurefor transformers,switches,timers,relays,sequencingunitsand othersimilardevicesshallbeof metalor of heatandmoistureresistant,non-combustiblematerial.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 373ELECTRICAL INSTALLATION OF BUILDINGS17.4.1.2 Construction(1) The enclosureshall be cC'nstructedto preventtheemissionof flamesor any burningorignitedmaterial.17.4.1.3 Ventilation(1) Openingsfor ventilationshallbearrangedto complywiththerequirementof 17.4.1.2andshallat leastbe 100.0mmfromlive parts.17.4.1.4 Thickness(1) Metal enclosuresshallnotbe lessthanO.8mmthickandat thepointwhereit is intendedthatthesupplyconnectionsbemade,theenclosureshallbeof notlessthan1.6mmin thickness.17.4.1.5Marking(1) Eachenclosurehousinga transformershallbemarkedin accordancewiththerequirementsof Clause2.4.6.17.4.2Protectionof UninsulatedPart(1) Doorsor coversaccessibleto thegeneralpublicandwhichgiveaccesstouninsulatedpartsof indoorsignsor outlinelightingshalleitherbeprovidedwith interlockswitcheswhich,ontheopeningof thedoorsor covers,disconnecttheprimarycircuitor shallbe fastenedso thattheuseof otherthanordinarytoolswill benecessaryto openthem.17.4.05 Transformers17.4.3.1 Secondaryvoltage(1) The ratedsecondaryopen-circuitvoltageof transformersshallnot exceed15.0kV,exceptas in (2) below.(2) In end-earthedtransformers,ratedsecondaryopen-circuitvoltageshallnotexceed7.5kV.f ..374 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 17: SIGNS AND OUTLINE LIGHTING17.4.3.2. Opencore-and-coiltypetransformer(I) Opencore-and-coiltypetransformersshallonly beusedindoor.17.4.3.3 Transformersusedoutdoors(I) Transformersusedoutdoorshallbeof theweather':'prooftypeor shallbe enclosedin thesignbodyor in a separateweather-proofbox.17.4.3.4 Installation(1) Transformersshallbeinstalledinsuchlocationthattheyareaccessibleandcapableof beingremovedandreplaced.(2) Theyshallbesupportedby attachmentto theenclosurein whichtheyarehousedby at leasttwo studsor bolts.17.4.3.5 Overcurrentprotection(1) Each transformershall be protectedby an overcurrentdeviceexceptthattwo or moretransformersmaybeprotectedby oneove-currentdeviceif theircombinedloaddoesnotexceed12.0A.17.4.4High-VoltageWiring Methods17.4.4.1 Conductorinstallation(I) High-voltageconductorsshallbe installedin:a) transformerenclosure,b) signenclosure,c) flexiblemetalconduit,d) rigid conduit,ore) otheracceptabletypeof racewaysexceptfor surfaceraceways.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 375ELECTRICAL INSTALLATION OF BUILDiNGS17.4.4.2 Conductorsrun(1) High-voltageconductorsmayberun fromtheendsof gastubesto theearthedmidpointoftransformerswhichhaveterminalsatthemidpoint.17.4.4.3 Bends(1) Thereshallbeno bendsin high-voltageconductors.17.4.4.4 Typeof conductors(1) All high voltage conductorsinstalledinside metal sign enclosuresshall be of theluminous-tube-signtypecables.17.4.4.5 Lengthof cablefrom transformers(1) In a metalicracewayandin a non-metallicraceway,cablesnotmorethana totalof 6.0mand 16.0m,respectively,shallberun fromtransformerto otherpartsof thesign.17.4.4.6 Connectionof conductors(1) Connectionof high-voltageconductorstoneontubingoutsidethebuildingor structureshallbe madeby meansof oneof thefollowing.a) anelectrodereceptacle;b) adirectconnectionin theneontubingoutsidethebuildingor structurewallprovidedthatnot morethan1.0mof high-voltagewiring extendsbeyondtheendof theraceway;c) anyotheracceptablemethods.Note: The connectionin (b) shallbeelectricallysecureandprovidedwithacceptablewrappingof insulatingtape.376 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18LIFTS, ESCALATORS AND SIMILAREQUIPMENT18.1 SCOPE(1) This Sectionappliesto the installationof electricalequipmentfor passenger,good'sordual-purposeelevators(lifts), includingdumbwaiters,escalators,movmgwalks,freightplatformlifts, andelevatingdevicesfor thehandicapped.18.2 NORMATIVE REFERENCES(1) Thefollowingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.a) C 22.1:1990 CanadianElectric(ilCodePart I, SafetyStandardfor ElectricalInstallations,SixteenthEdition.b) NFPA 70/NEC:1986 National Firr Protection Association/AmericanNationalElectricalCode,1987Edition.18.3 GENERAL18.3.1 VoltageLimitation(1) The nominal voltageusedfor lift operatingcontrol and signallingcircuits,operatingequipment,drivingmachinemotors,machinebrakes,andmotorgeneratorsetsshallnotexceedthefollowing:a) 380.0Y for operatingcontrolandsignallingcircuitsandrelatedequipment,includingdooroperatormotors.b) 750.0Y for drivingmotors,machinebrakes,andmotor-generatorsets.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 377ELECTRICAL INSTALLATION OF BUILDINGSExemption: Higher voltagesshall be pennittedfor drivingmotorsof motorgeneratorsets.18.3.2LivePartsEnclosed(1) All livepartsof electricapparatusin hoistways,atlandingsor inor onthecarsof lightsanddumbwaitersor in thewell-waysor thelandingof escalators,or movingwalksshallbeenclosedto protectagainstaccidentalcontact.18.4 CONDUCTORS18.4.1Installationof Conductors18.4.1.1Hoistwaydoorinterlockingwiring(1) The conductorsto the hoistway door interlocksfrom the hoistway riser shall beflame-retardantandsuitablefor temperatureof not lessthan200C.18.4.1.2 Travellingcables(1) Travdling cablesusedasflexibleconnectionsbetweenthelift carandtheracewayshallbeof thetypesof lift cablesor otherapprovedtype.18.4.1.3 Otherwiring(1) All conductorsin raceways,in or onthecarsof lifts anddumbwaiters,in thewell-waysofescalatorsandmovingwalks,andin themachineroomof lifts, escalators,andmovingwalksshallhaveflame-retardantinsulation.18.4.1.4 Insulationrating(I) All conductorsshallhaveaninsulationvoltageratingequaltoatleastthemaximumnominalcircuitvoltageratingof anyconductorwithintheenclosure,cableor raceway.18.4.2MinimumSizeof Conductors(1) The minimumsizeof conductorsusedfor lifts,dumbwaiters,escalators,andmovingwalkwiring,otherthanconductorsthatformsanintegralpartof controlequipment,shallbeasfollow:378 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18: LIFTS, ESCALATORS AND SIMILAR EQUIPMENTa) for lightingcircuits,1.5mm2;andb) for operatingcontrolandsignallingcircuits,0.5mm218.4.3Motor Circuit Conductors(l) Conductorssupplyinglifts, dumbwaiters,escalator,or movingwalk motorsshallhaveanampacityof:(a) if supplyingsinglemotor,not lessthan150%of themotorfull-loadcurrentrating.(b) if supplyingtwo or moremotors,not lessthan125%of thenameplatecurrentratingof thehighestratedmotorin thegroupplusthesumof thenameplatecurrentratingsof theremainderof themotorsin thegroup.18.5 WIRING18.5.1Wiring Methods18.5.1.1 In hoistway,machinerooms,andescalatorwellways(l) Conductorslocatedin hoistway,machineroomsandescalatorwell-ways,excepttravellingcables,shallbe installe~in rigid metalconduit,electricalmetallictubing,or metalwireways,exceptthatflexiblemetalconduitor armouredcableshallbepermittedonly if notsubjectedtomechanicaldamage.Exemption: Mineral-insulatedcableor aluminium-sheathedcablemaybeusedif locatedsothatthereis no liabilityof damageto the sheath.18.5.1.2 (In cars(l) Conductorson lift and dumbwaitercars shall be run in rigid metalconduit,electricalmetallictubing,or wireways,exceptthat:a) shortrunsof flexible metalconduitor armouredcablemaybe usedwherethey aresecurelyfastenedin placeandnotexposedto oil or grease;b) hardusageflexiblecordshallbepermittedto beusedbetweenfixedwiring on thecarand switchingor sensingdeviceson the door or gate,andbetweenthe fixed car topinspectionlight and an extensionlight controlledby the sameswitch,providedit issecurelyfastenedandso locatedasto notbesubjectto mechanicalinjury;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 379ELECTRICAL INSTALLATION OF BUILDINGSc) mineral-insulatedcable.or aluminium-sheathedcablemaybeusedif locatedsothatthereis no liability or damageto thesheath.18.5.2 BranchCircuitsfor AuxiliarySystems18.5.2.1 Carlightingandaccessories(1) In passengerlifts, at leastonebranchcircuitshallbeprovidedsolelyfor the lightingandaccessorieson eachcar.18.5.2.2Air conditioning(1) Whereair conditioningunitsare installedon thecar, theyshallbe suppliedby separatebranchcircuits.18.5.2.3 Protectiondevicelocation(1) Theovercurrentdeviceprotectingeachbranchcircuitshallbelocatedin themachineroom.18.6 INSTALLATION OF CONDUCTORS18.6.1Numberof Conductorsin Raceway(1) The sum of the cross-sectionalareaof the operatingand control circuit conductorsInracewaysshallnotexceed40%theinteriorcross-sectionalareaof theraceway.18.6.2Supports(1) Supportsfor cablesor racewaysin ahoistwayor in anescalatoror movingwalkwaysshallbe securelyfastenedto theguiderail or to hoistwaywell-wayconstruction.18.6.3DifferentSystemsin OneRacewayor TravellingCable(1) Conductorsfor operating,control,power,signallingandlightingcircuitsof 600.0Yor lessshallbepermittedto berun in thesametravellingcableor racewaysystemif all conductorsareinsulatedfor maximumvoltagefoundin thecablesor racewaysystemandif all livepartsof theequipmentareinsulatedfrom earthfor themaximumvoltage.380 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18: LIFTS, ESCALATORS AND SIMILAR EQUIPMENT(2) Such travellingcableor racewayin (1) aboveshall be pennittedto includeshieldedconductorsand/oroneor morecoaxialcableif suchconductorsareinsulatedfor themaximumvoltagefound in cableor racewaysystem.Conductorsshallbepennittedto becoveredwithsuitableshieldingfor telephone,audio,videoor higherfrequencycommunicationcircuits.18.6.4Wiring in Hoistway(1) Main feedersfor supplyingpowerto lifts anddumbwaitersshallbe installedoutsidethehoistway(hoistshaft).Note: Only wiring, raceways,andcablesthatareor formpartof lift or dumbwaiterinstallation,includingwiringfor signals,for communicationwith thecar,for lighting,heating,air conditioningandventilatingth~car,for fire detectingsystems,for pitpumps,andfor heatingandlightingthehoistway,shallbepermittedinsidethe hoistway.18.6.5ElectricEquipmentin GaragesandSimilarOccupancies(1) Electricequipmentandwiringusedfor lifts,dumbwaiters,escalators,andmovingwalksingaragesshall complywith the requirementsof Section12 (ClassI locations). Wiring andequipmentlocatedon theundersideof thecarplatfonnshallbeconsideredasbeinglocatedinthehazardousarea.18.6.6SidewalkLifts(1) Sidewalklifts with sidewalkdoorslocatedexteriorto thebuildingshallhaveall electricalwiring in metallictubingandall electricaloutlets,switches,junctionboxesandfittingsshallbeweather-proof.18.7 TRAVELLING CABLES18.7.1Suspension(1) Travellingcablesshallbesosuspendedatthecarandhoistway'sendsasto reducethestrainon the individualcopperconductorsto a minimumand shall be supportedby one of thefollowing means:a) by its steelsupportingmembers;b) by loopingthecablearoundsupportsfor unsupportedlengthslessthan30.0m;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 381ELECTRICAL INSTALLATION OF BUILDINGSc) by suspendingfromthesupportsby meansthatautomaticallytightensaroundthecablewhentensionis increasedfor unsupportedlengthsupto60.0m.18.7.2Hazardous(Classified)Location(1) In hazardous(classified)locations,travellingcablesshall be of a type approvedforhazardous(classified)locationsandshallbesecuredto explosion-proofcabinets.18.7.3ProtectionAgainstDamage(1) Travellingcablesupportsshallbeso locatedasto reduceto a minimumthepossibilityofdamageduetothecablecomingintocontactwiththehoistwayconstructionor equipmentin thehoistway;andwherenecessary,suitableguardsshallbe providedto protectthecableagainstdamage.18.7.4Installation(1) Travellingcableshallbepermittedto berunwithouttheuseof racewayor conduitfor adistancenot exceeding1.8mfrom the first pointof supporton the lift car or hoistwaywallprovidedtheconductorsaregroupedtogetherandtappedor cordedor in theoriginalsheath.(2) Travellingcablesshallbepermittedtobecontinuedto lift controlpanelsandto lift carandmachineroomconnectionsasfixedwiring providedtheyaresuitablysupportedandprotectedfrom damage.18.8 DISCONNECTING MEANS AND CONTROL18.8.1General(1) Lifts, dumbwaiters,escalators,and moving walks shall have a single means fordisconnectingall unearthedmainpowersupplyconductorsfor eachunit.(2) Wheremultipledrivingmachinesareconnectedto a singlelift, escalator,movingwalk orpumpingunit, thereshallbe onedisconnectingmeansto disconnectthemotor(s)andcontroldevices.382 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18: LIFTS, ESCALATORS AND 'SIMILAR EQUIPMENT(3) Wherethereis morethanonedrivingmachinein a machineroom,disconnectingmeansshallbenumber-markedto correspondto thenumber-markof thedrivingmachinewhichtheycontrol.18.8.2Type(1) The disconnectingmeansshall be an enclosed,externallyoperable,fusedmotor circuitswitchor circuitbreakerto be lockedin theopenposition.(2) No provisionshallbemadeto closethedisconnectingmeansin (1) abovefrom anyotherpartof thepremises;nor shallcircuitbreakersbeopenedautomaticallyby a fire alarmsystem.18.8.3Location(1) Disconnectingmeansshallbelocatedwheretheyarereadilyaccessibletoqualifiedpersons.18.8.4 PhaseProtection18.8.4.1Electriclifts(1) Lifts.drivenby polyphasealternatingcurrentshallbe providedwith a meansto preventstartingof thelift when:a) thephaserotationis in thewrongdirection,orb) thereis a failurein anyphase.18.8.4.2Hydrauliclifts(1) Hydrauliclifts poweredby apolyphasealternatingcurrentmotorshallbeprovidedwiththemeansto preventoverheatingof the drive system(pumpand motor)dueto phase-rotationreversalsor failure.18.9 OVERCURRENT PROTECTION18.9.1ControlandOperatingCircuits(1) Controlandoperatingcircuitsandsignallingcircuitsshallbeprotectedagainstovercurrentin accordancewith therequirementsof therelevantClausesof Section9.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 383ELECTRICAL INSTALLATION OF BUILDINGS18.9.2 Motors18.9,2,1 Non-continuousduty(1) Dutyonlift anddumbwaiterdriving-machinemotorsanddrivingmotorsof motor-generatorsusedwith generatorfield controlshall beclassedas non-continuous.Such motorsshallbeprotectedagainstovercurrentin accordancewith applicableClausesof Section11.18.9,2.2 Continuousduty(1) Duty on escalatorsandmoving-walkdrivingmotorsshallbeclassedascontinuous.Suchmotors shall be protectedagainstovercurrentin accordancewith applicableClausesofSection11.18.10 MACHINE ROOM18.10.1 GuardingEquipment(1) Lifts, dumbwaiters,escalators,andmovingwalk drivingmachines,motor-generatorsets,motorcontrollers,anddisconnectingmeansshallbe installedin a roomor enclosuresetasidefor thatpurpose.(2) The roomor theenclosurein (1) aboveshallbesecuredagainstunauthorizedaccess.18.10.2 ClearancearoundControlPanelsandDisconnectingMeans(1) Sufficientclearworkingspaceshallbeprovidedaroundcontrolpanelsanddisconnectingmeansto providesafeandconvenientaccessto all live partsof theequipmentnecessaryformaintenanceandadjustment.18.11 EARTIllNG18.11.1 MetalRacewayAttachedtoCars(1) Metal racewaysattachedto lift carsshallbebondedto earthedmetalpartsof thecarwithwhich theycomeintocontact.384 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18: LIFTS, ESCALATORS AND SIMILAR EQUIPMENT18.11.2 ElectricLifts(1) For electric lifts, the framesof all motors,lift machines,controllers,and the metalenclosuresof all electricdevicesin or on the car or in the hoistwayshall be earthedinaccordancewith Section7.18.11.3 Non-ElectricLifts(1) For lifts otherthanelectricandhavinganyelectricconductorsattachedto thecar,themetalframeof the car, wherenormallyaccessibleto persons,shallbe earthedin accordancewithSection7.18.11.4 Methodof Bonding18.11.4.1Equipment(1) Equipmentmountedonmembersof anearthedstructuralmetalframeof abuildingshallbedeemedto bebondedto earth.18.11.4.2Metalcarframesupportedbycables(1) Metal car framessupportedby metalhoistingcablesattachedto or runningover metalsheavesor drumsof lift machinesand affordingmetal-to-metalcontacttherewithshall bedeemedto be bondedto earthwhen the machineis bondedto earthin accordancewithSection7.18.12 OVERSPEED18.12.1 OverspeedProtection(1) Underoverhaulingloadconditions,ameansshallbeprovidedontheloadsideof eachliftpowerdisconnectingmeansto preventthe lift from attaininga speedequalto the governortrippingspeedor a speedin excessof .125%of thelift ratedspeed,whicheveris smaller.(2) Overhaulingloadconditionsshallincludeall loadsuptoratedlift loadsfor goodslifts andall loadsupto 125%for theratedlift loadsfor passengerlifts.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 385____ ~~~~~~~~~~~J.4lELECTRICAL INSTALLATION OF BUILDINGS18.12.2 Motor-GeneratorOverspeedDevice(1) Motor generatorsdrivenby directcurrentmotorsandusedto supplydirectcurrentfor theoperationof lift machinemotorsshallbeprovidedwithspeed-limitingdevicesthatwill preventthe lift from attaining,atanytime,a speedof morethan125%of its ratedspeed.18.13 EMERGENCY POWER18.13.1 Supply(1) A lift shallbepermittedtooperatefromanemergencypowersupplyin theeventof normalsupplyfailure, providedthe lift operateson suchemergencypower in accordancewith theemergencypowersystemrequirementsof a recognizedinternationalsafetycodefor lifts.18.13.2 Disconnection(1) The disconnectingmeansshalldisconnecttheemergencypowerservicefrom thenormalpowerservice.18.13.3 HydraulicLifts DisconnectingMeans(1) In thecaseof hydrauliclifts whereemergencypoweris suppliedfroma secondsourceforloweringthecaronly,thedisconnectingmeansshallbeprovidedwith anauxiliarycontactthatis positivelyopenedmechanically,the openingnot beingsolely dependenton springs,andconnectedin thecontrolcircuitto preventmovementof thecarwhenthedisconnectingmeansis open.18.14 MACHINE ROOMS AND HOISTWAY PITS LIGHTING AND AUXILIARYSYSTEMS18.14.1 MachineRoom18.14.1.1Lighting(1) Permanentprovisionof adequateartificiallightshallbemadein machineroomsof powerlifts.386 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 18: LIFTS, ESCALATORS AND'SIMILAR EQUIPMENT18.14.1.2Illuminationlevel(I) IHuminationshallbenot lessthanlOO.O/x at floor level.18.14.1..3Lightingswitch(1) Themachineroomlightingswitchshallbewithineasyreachof theentrancetothemachineroom.18.14.1.4Socketoutlet(1) At leastoneduplex(twin) socketoutletconnectedto 16.0Abranchcircuit supplyingno.othersocketoutletsshallbe installedin themachine room.18.14.2 HoistPits18.14.2.1Luminaire(I) -OneQfmotep.ennaAentluminaireequippedwith a guar.dof metal,safetyglassorsuitableplasticmatedalshaHtbeprovidedin aUpits.t8.14.2.2 IlluminationlevelThe luminairesshallprovideanilluminationslevel of at leastlOO.O/x atthepit floor.18.14.2.3Lightingswitch(I) A Hghtswitchshall 'be'provided,andshallbe locatedso aslobe accessiblefrom thepitaccessdoor.18.14.2.4Socketoutlet(1) At leastonetwin socketoutletconnectedto a 1'6:0Abranchcircuit supplyingno othersocketoutletshall,beinstalledin .each;pit.EIHUOPIAN ,BUILDING ,CODE STANDARD EBCS-10 1995387SECTION 19THEATRE INSTALLATION19.1 SCOPE(1) This Sectionappliesto electricalequipmentandtheirinstallationsin buildingsor parts'ofa buildingdesigned,intended,or usedfor drama,opera,motionpicture,or othershows.19.2 NORMATIVE REFERENCES(1) The followingreferencecontainsprovisionswhich,throughreferencein thistext,constituteprovisionsof ,theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.a) C22.1:1990 CanadianElectrical Code, Part 1, Safety Standardfor ElectricalInstallation,SixteenthEdition.19.3 WIRING METHOD(1) Wiring in stageandstagewingareas,orchestrapits,andprojectionboothsshallbein rigidmetalconduit,armouredcable,lead-sheathedarmouredcable,or aluminium-sheathedcableexceptthat:a) otherwiring methodsshallbepermittedfor temporarywork,andb) flexiblecordor cableshallbepermittedinaccordancewithotherClausesin thisSection.(2) Surfaceracewaysshallnotbeusedonthestagesideof theprosceniumwall.(3) Wiring in areasother thanthoselisted in (1) aboveshall be in accordancewith therequirementsof theappropriateSectionsof thisCode.(4) Circuitsfor aislelightslocatedunderseatsmaysupply30 outletsprovidedthatthesizeoflampwhich can,be usedwith eachoutletis limitedby barriersor theequivalentto 25.0Worless.388 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 19: THEATRE INSTALLATION19.4 FIXED STAGE SWITCHBOARD(1) Stageswitchboardshallbe:a) of thedead-fronttype,andb) protectedabovewith a suitablemetalguardor hoodextendingthefull lengthof theboardandcompletelycoveringthespacebetweenthewall andtheboardto protectthelatterfrom falling objects.(2) Wherea stageswitchboardhasexposedlive partson the backof theboard,it shall beenclosedby thewalls of thebuilding,by wire meshgrills, or by otheracceptablemethods.(3) The entranceto theenclosuresshallhavea self-closingdoor.(4) Switchesshallbeof theenclosedtypeandexternallyoperated.(5) Pilot lampon switchboardshallbe:(a) installedwithin everyswitchboardenclosure,(b) connectedto thecircuitsupplyingthe'switchboardsothattheopeningof themasterswitchdoesnotcutoff thesupplyto the lamp,and(c) onan independentcircuitprotectedby anovercurrentdeviceratedor setatnotmorethan15.0A.19.4.1Fuses(1) Fuseson switchboardsshallbe:a) of eithertheplug or cartridgetype,andb) providedwith enclosuresin additionto theswitchboardenclosure.19.4.2OvercurrentProtection(1) All circuitsleavingtheswitchboardshallhaveanovercurrentprotectiondeviceconnectedin eachunearthedconductor.//ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 389ELECTl1lCALINSfALtAflON OF BUILDINGS,~, , '_'_~' __'_SECTION 19: THEATRE INSTALlATION19.5 PORT ABLE SWITCHBOARD ON STAGE19.5.1 Construction of Portabl~Switc'bo~rds(1) portableswitchboardsshallbepla~edwithin~nclosureof substanti!llconstruction;buttheymaybe arrangedsothattheenclosureis openduringoperation.(2) Then~shallbeno livepartsexposedwit.hinthe,enclosure.~x.ceptthos~.on.dimmerfaqeplates.19.5.2 Supplyfor Portable SwjtcbbOjlrd(1) Portableswitchboardsshallbe suppliedby meansof flexiblecordelfcable.of e.xtra'bardusagetypetenninatingwithin the switchboardenclpslrein an e~ternclllyoperated,en~loseQ~fusedmasterswitch.(2) Themasterswitchin (1) llboveshallbearrMgedsoastelcytoff qurr~l1tfromall apparatus.within theencloslreexceptthepilot light.(3) The flexiblecordor cableshallhavesufficient~apcity to carrythetotalload,CijITentoftheswitchboard.(4) The ampere-ratingof thefusesof them!lsterswitchshallnotbegreaterthantiletQtlllloaQcurrentof theswltehboCU'd.19.6 FIXED STAGE EQUIPMENT19.6.1 FoptHght$(1) Where footlightsare wired in rigid metalconduitor electricalme.taJli9tubing, everylampholdershallb~instllUedin an indivig)Jaloutletbox.(2) Wherefootlightsarenotwiredin rigidmetalconduitorelectricalmet/dUetubing,thewiringshallbe installedin a metllltrough.19.6.2 Metalwork(1) The metalworkfor footlights,borders,pro!!ceniu!llsidelights,andstripsshallnot be les'thanQ.8mmthick.ETHIOPIAN BUILDING CODE STANDARD EBC$-1 0 199~ 391ELECTRICAL INSTALLATION OF BUILDINGS(2) The metalworkfor bunchesandportablestripsshallbenot lessthanO.5mmthick.19.6.3ClearanceatTerminals(1) The terminalsof lampholdersshallbe separatedfromthemetalof thetroughby at least13.0mm.19.6.4MechanicalProtection(1) Borders,prosceniumsidelights,andstripsshallbe constructedso thatthe flangesof thereflectorsor othersuitableguardsprotectthelampsfrommechanicalinjuryandfromaccidentalcontactwith sceneryor othercombustiblematerial.19.6.5SuspendedFixtures(1) Bordersandstripsshallbeso suspendedasto beelectricallyandmechanicallysafe.19.6.6ConnectionsatLampholders(1) Conductorsshallbesolderedtotheterminalsof lampholdersunlessothersuitablemeansare provided'toobtainpositiveandreliableconnectionunderseverevibration. -,19.6.7Ventilationfor MogulLampholers(1) Wherethelightingdeviceareequippedwithmogullampholders,thelightingdevicesshallbeconstructedwith doublewallsandwith adequateventilationbetweenthewalls.19.6.8ConductorInsulationfor Field-AssembledFixtures(1) Foot, border,proscenium,andportablestriplightfixturesassembledin the field shallbewiredwithconductorshavinginsulationsuitableforthetemperatureatwhichtheconductorswillbeoperated;but in no caseshallthedesigntemperaturebe lessthan125C.19.6.9BranchCircuitOvercurrentProtection(1) Branchcircuitsfor footlights,borderlights,andprosceniumsidelightsshallhaveovercurrentprotectionin accordancewith 15.3.1.4.392 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 19: THEATRE INSTALLATION19.6~10PendantLightsRatedMoreThan100.0W(1) Where.apendentlightingdevicecontainsa lampor groupof lampsof morethanIOO.OWcapacity,it shallbe providedwith a guardof notmorethan13.0mmmeshso arrangedastopreventdamagefrom falling glass.19.6.11Cablesfor BorderLights(1) Flexible cordor cablefor borderlightsshallbeof extra-hard-usagetype.,(2) The flexiblecordor cableshallbefedfrompointsonthegridironor fromotheracceptableoverheadpoints;buttheyshallnotbe fedfrom sidewalls.(3) The flexiblecordor cableshallbearrangedsothatstrainistakenfromclampsandbindingscrews.(4) Wherethe flexible cord or cablepassesthrougha metalor woodenenclosure,a metalbushingshallbeprovidedto protectthecord.(5) Terminalsor bindingpoststo which flexible cordsor cablesare connectedinsidetheswitchboardenclosureshallbe locatedso asto permitconvenientaccessto them.19.6.12 Wiring to Arc Pockets(1) Wherethewiring to arcpocketsis in rigid metalconduitor electricalmetallictubing,the,endof theconduitor tubingshallbeexposedatapointapproximately300.0mmawayfromthepocket,andthewiring shallbecontinuedin flexiblemetalconduitin theformof a loopat least600.0mmlong,with sufficientslackto permittheraisingor loweringof thebox.19.6.13 SocketOutletsandPlugs(1) Socketoutletsintendedfor theconnectionof arclampsshall:a) haveanampereratingnot lessthan40.0A,andb) be suppliedby copperconductorsnotsmallerthan16.0mm2ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 393ELECTRICAl- INSTALLATION OF BUILDINGS(2) Socketoutletsintendedfor theconnectionof incandescentlampsshall:a) haveanampereratingnot lessthan16.0A,andb) besuppliedby conductorsnotsmallerthan4.0mm2copperor 6.0mm2aluminium.(3) Plugs for arcandincandescentsocketoutletsshallnotbe interchangeable.19.6.14 CurtainMotors(1) Curtainmotorsshallbeof theclosedtype.19.6.15 FlueDamperControl(1) Wherestageflue dampersarereleasedby an electricaldevice,the circuit operatingthedeviceshall,in normaloperation,beclosed.(2) The circuitshallbecontrolledby atleasttwo single-poleswitchesenclosedin metalboxeswith self-closingdoorswithoutlocksor latches.(3) One switchshallbeplacedattheelectrician'sstationandtheotherata suitableplace.(4) The deviceshallbe:a) designedfor thefull voltageof thecircuitto whichit is connected,or resistancebeinginserted;b) locatedin theloft abovethescenery;andc) enclosedin a suitablemetalboxwith a tightself-closingdoor.19.7 PORTABLE STAGE EQUIPMENT19.7.1FixturesonScenery(1) Fixturesattachedto stagesceneryshallbe:a) of the internallywiredtype,orb) wiredwith flexiblecordor cablesuitablefor hardusage.(2) The fixturesshallbesecuredfirmly in place.394 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 19: THEATRE INSTALLATION(3) The stemsof thefixturesshallbecarriedthroughto thebackof thesceneryandshallhavea suitablebushingontheendthereof.19.7.2Stringor FestoonedLights(1) Joints in thewiring of stringor festoonedlightsshallbestaggeredwherepracticable.(2) Wherethelampsof stringor festoonedlightsareenclosedinpaperlanterns,shades,orotherdevicesof combustiblematerial,theyshallbeequippedwith lampguards.19.7.3FlexibleConductorsfromPortableEquipment(1) Flexibleconductorsfor arclamps,bunches,or otherportableequipmentshallbeof extra-hard-usagetypecordor cable;butfor separatemiscellaneousportabledevicesoperatedunderconditionswheretheconductorsarenotexposedto severemechanicalinjury,reinforcedcordsof ordinarytypemaybeusedprovidedthattheyareprotectedby anovercurrentdeviceratedor setatnot morethan16.0A.19.7.4PortableEquipmentfor StageEffects(1) Portableequipmentfor stageeffectsshallbeof a typeacceptablefor thepurposeandshall~be so locatedthat flames,sparks,or hot particlescannotcomein contactwith combustiblematerial.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 395SECTION 20EMERGENCY SYSTEMS, UNITEQUIPMENT, AND EXIT SIGNS20.1 SCOPE(1) This Sectionappliesto:a) the installation,operationandmaintenanceof emergencysystemandunit equipmentintendedto supplyilluminationandto emergencysystemsintendedto ~upplypower,whererequiredby theauthorityhavingjurisdiction,andb) thewiringof exitsigns.20.2 NORMATIVE REFERENCE(1) The followingreferencecontainsprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings.a) C22.1:1990 CanadianElectrical Code, Part 1, Safety Standardfor ElectricalInstallations,SixteenthEdition.20.3 GENERAL20.3.1Capacity(1) Emergencysystemsandunitequipmentshallhaveadequatecapacityandratingto ensurethesatisfactoryoperationof all connectedequipmentwhenthegeneralpowersupplyfails.396 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 20: EMERGENCY SYSTEMS, UNIT EQUIPMENT, AND EXIT SIGNS20.3.2Instruction(1) Completeinstructionsfor theoperationandmaintenanceof theemergencysystemor unitequipmentwhich shall also specifytestingat leastonceeverymonthtd ensuresecurityofoperation,shallbepostedonthepremisesin a frameunderglass.20.3.3BatteriesMaintenance(1) Whenbatteriesareusedasa sourceof supply,thebatteriesshallbekept:a) in propercondition,andb) fully chargedatall times.20.3.4Lamps(1) Emergencylightsshallbeso arrangedthatthefailureof onelampwill not leavetheareanormallyilluminatedby it in totaldarkness.20.3.5Circuits(1) No applianceor lamp,otherthanthosereq~iredfor emergencypurposes,shallbesuppliedby theemergencycircuits.20.3.6 Methodof Wiring20.3.6.1 General(1) The methodof wiring, includingthatbetweenunitequipmentandremotelamps,shallbein accordancewith theprovisionsof Section8.20.3.6.2 Segregation(1) The wiring shallbekeptentirelyindependentof all otherwiring andequipmentandshallnotentera fixture,raceway,box,or cabinetoccupiedby otherwiring except,wherenecessary:a) in transferswitch,andb) in emergencylightingfixturessuppliedfromtwo sources.ETHIOPIAN EmlIDING CODE STANDARD EBCS-10 1995 397ELECTRICAL INSTALLATION OF BUILDINGS20.4 EMERGENCY SYSTEMS20.4.1Supply(1) The emergencysupplyshallbea standbysupplyconsistingof:a) a storagebatteryof the rechargeabletype havingsufficientcapacityto supplyandmaintainthetotalloadof theemergencycircuitsatnotlessthan91% of thefull voltagefor thetimeperiodrequiredbytheauthorityhavingjurisdiction,butin nocaselessthanY2hr,and be equippedwith a chargingmeansto maintainthe batteryin a chargedconditionautomatically.Note: Automobilebatteriesandleadbatteriesnotof theenclosedglass-jartypearenotconsideredsuitable.b) a generatordrivenby a dependableprimemoverandit shallbe:i) of capacitysufficientto carrytheload,andii) ~rrangedto startautomaticallywithoutfailure andwithoutunduedelayupon thefailureof thecurrentsupplyof theprincipalequipmentof thebuilding.iO.4.2 Control(1) The currentsupplyfor emergencysystemsshall be controlledby an automatictransferswitchwhichenergizestheemergencysystemuponfailureof thenormalcurrentsupplyandisaccessibleonly to authorizedpersons.20.4.3OvercurrentProtection(1) No devicecapableof interruptingthecircuit,otherthanthe overcurrentdevicefor thecurrentsupplyof theemergencysystem,shallbeplacedaheadof thebranchcircuitovercurrentdevice.20.4.4 AudibleandVisualTroubleSignalDevices20.4.4.1 Troublesignal(1) Every emergencysystemshallbeequippedwith audibleandvisualtroublesignaldeviceswhichgivewarningof derangementof thecurrentsourceor sourcesandwhich indicatewhentheemergencyloadis suppliedfrombatteriesor generators.398 EBCS10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 20: EMERGENCY SYSTEMS, UNIT EQUIPMENT, AND EXIT SIGNS20.4.4.2Wiring(1) Audible troublesignalsmaybewiredsothat:a) they canbe silenced,but a red-warningor troublelight shallcontinueto providetheprotectivefunction, andb) whenthesystemis restoredto normal,theaudiblesignalwiU:i) sound,thus indicatingthenecessityof restoringthes.ilencingswitchto its normalposition,orii) resetautomaticallyso as to soundfor any subsequentoperation'of theemergencysystem.20.4.4.3Voltagedrop(1) Thevoltagedropin thewiringfeedinglampsmountedremotefromthe'currenfsupplyshaHnotexceed5% of theappliedvoltage.20.S UNIT EQUIPMENT20.S.1Mounting(1) Each unit equipmentshall be mountedwith thebottomof enclosurenot'less than2.0mabovethe floor whereverpracticable.Note: Unit equipmentfor 'emergencylighting is defined,asan-itemof equipmentthat:i) is intendedtoprovideautomatically, inresponseto,afailure of apowersupply'towhich it is connected,'specified,lightoutputanda specifiedamountof powerfor illuminationpurposes,for a specifiedperiodof time,but in any casenot:Iessthan 30.0min;ii) comptises,in'aunitconstruction,a storagebattery,'chargingmeanstomaintainthebatteryin achargedconditionautomatically,lamps,otoutputterminalsto whichspecificallylistedlampsmay beconnected,meansto energizethelampswhenthenormalpowersupplyfails andto de-energizethelampswhenthenormal power supply is reStored,andmeans to indicateand testthe operatingconditionsof theequipment.ETHIOPIAN BUilDING CODE STANDARD iEBCS..:10 1'995 399ELECTRICAL INSTALLATION OF BUILDI~GS20.5.2 SupplyConnections20.5.2.1 Outletdistance(1) Outletpointto whichunitequipmentis to beconnectedshallbenotmorethan1.5m.fromthe locationof theunitequipment.20.5.2.2 Connectiontosupply(1) Unit equipmentshallbepermanentlyconnectedto thesupplyif:a) thevoltageratingexceeds230.0V,orb) themarkedinputratingexceeds24.0A.(2) Wheretheaboveratingsarenotexceeded,theunitequipmentmaybeconnectedusingtheflexiblecordandattachmentplugsuppliedwiththeequipment.20.5.2.3 Installation(1) Unit equipmentshallbe installedin sucha mannerthatit will beautomaticallyacthlateduponthe failureof thepowersupplyto thenormallightingin theareacoveredby thatunitequipment.20.5.2.4 Feeding(1) Unit equipmentshallbefed,wherepracticable,fromthesamepanelboard,andmaybefedfromthesamebranchcircuitwhichfeedsthenormallightingin theareacoveredby thatunitequipment.20.5.2.5 Voltagedrop(1) The circuitconductorsto lampsmountedremotefromsupplysourceshallbeof suchsizethatthevoltagedropdoesnotexceed5% of themarkedoutputvoltageof theunitequipment.20.5.2.6 Excessload(1) The numberof lampsconnectedto singleequipmentshallnot resultin a loadthatis inexcessof thewattoutputratingmarkedontheequipmentfor therequiredemergencyperiod.400 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 20: EMERGENCY SYSTEMS, UNIT EQUIPMENT, AND EXIT SIGNS20.6 EXIT SIGNS20.6.1 Power Supply(1) The powersupplyfor exitsignsshallbeprovidedfrom:a) a separatecircuitor circuitsusedfor no otherpurpose,orb) thecircuitsupplyingexit lighting20.6.2 Wiring(1) Exit signsshallbewired in accordancewiththeprovisionsof Section8 of thisCode.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 401SECfION 21MOTION PICfURE STUDIOS, PROJECTIONROOMS, FILM EXCHANGES AND FACTORIES21J. SCOPE(1) ThisSectionsetsprovisionsandinstallationrequirementsthatapplytomotion-picturestudios,projectionrooms,exchanges,factoriesandanybuildingin whichmotion-picturefilms,pyroxylinplasticandnitrocellulosex-rayandphotographicfilmsaremanufactured,projected,developed,printed,rewound,repairedor stored.21.2 NORMATIVE REFERENCES(1) Thefollowingr,eferencescontainprovisionswhich,throughreferenceinthistext,constituteprovisions,oftheEthiopianBuildingCodeStandardconElectricalInstallat,ionof Buildings:a) C22.1.:199(:) CanadianElectricalCode, Part 1, SafetyStandardforElectricalInstallations,SixteenthEdition.b) NFPA70/NEC:1986 NationalFire PwtectionAssociation/ AmericanNationalElectricalCode,1987Edition21.3 GENERAL21-.3.1Wir.ingMethod(1) Thewiringmethod,unlessspecifiedofherwiseinsubclauseof'thisSection,shallberigidconduit,steelelectricalmetallictubing,or mineral-insulatedcable.(2) The wiring for stage-setlighting,stage.,effects,electricequipmentused as stageproperties,,andotherwiringnotfixedasto location,shall'bedonewithapprovedflexiblecordsandcables.,402 EBCS-1G1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 21: MOTION PICTURE STUDIOS, PROJECTION ROOMS, ETC(3) For portable lampsother than thoseused aspropertiesin a motion-pictureseton astudio stageor similar location, the lampholdersshallbe:a) unswitched,b) of compositionor metalsheathedprocelain,andc) providedwith a guardhook and handle.21.4 VIEWING, CUTTING AND PATCHING TABLE FIXTURE(1) All lightingfixtures,exceptlampsformingan integralpartof tableequipment,shallbeof the totally-enclosedgaskettedtype.21.5 FILM VAULTS AND STORAGE ROOMS21.5.1 Equipment in Film Vaults and Storage.Rooms(1) In rooms used for storageof pyroxylinplastic,no socketoutlet or attachmentplugsshall be installed.(2) .No electricalequipmentother than thatnecessaryfor fixed lightingshall be installedin film vaults.21.5.2 Wiring Method in Film Vaults(1) The wiring methodin film-vaultshallberigid-conduitor mineral-insulatedcableonly,with threadedjoints at couplingsboxesand fittings.(2) Conduit or cableshallnot run directlyfromvault to vault,but only form the switchtothe lighting fixturewithin thevault.(3) Conduit shall be sealedoff near the switchenclosurewith a fitting and compoundapprovedfor the purpose.21.5.3 Lighting Fixtures in Film Vaults(l) Lighting fixturesin film vaultsshallbeof theexplosion-prooftypeapprovedfor theusein Class I Group C hazardouslocationsandshallhavemetalcagesor guardsprotectingtheglobs.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 403j~-LELECTRICAL INSTALLATION OF BUilDINGS(2) The fixturesin (1)aboveshallbelocatedascloseaspracticabletotheceilingtoavoidtheirbeingdamagedthroughhandlingof filmcontainers.21.5.4 Film Vault Circuits(1) Fixturesshallbecontrolledbya doublepoleswitchlocatedoutsidethefilmvault.(2) A redpilot lightshallbeprovidedto indicatewhentheswitchis closedandshallbelocatedoutsidethefilmvault.(3) Wiringshallbearrangedsothat,whentheswitchis off,all conductorswithinthefilmvaultwill bedead.21.6 MOTION PICTURE PROJECTION ROOMS21.6.1 Lamps in Projection Rooms(1) Incandescentlampsinprojectionroomsorboothsshallbeprovidedwitha lampguardunlessotherwiseprotectedbynoncombustibleshadesor otherenclosures.21.6.2 Arc Lamp Current Supply(1) Motorgeneratorsets,frequencychangers,transformers,rectifiers,rheostats,andsimilarequipmentfor thesupplyor controlof currentto arclampsor projectorsshallbe locatedin a roomseparatefromtheprojectionroom.21.6.3 Ventilation(1) Exhaustventilationfansfor theprojectionroomshallbecontrolledfrominsidetheprojectionroom.21.7 MOTORS AND GENERATORS(1) Motors andgeneratorshavingbrushesor slidingcontacts,otherthanthoseusedonstudiostagesor thoseinstalledin accordancewithClause21.6.2,shallbeofapproveddust-tightor enclosedtypes.404 EBCS-10 1995 ETHIOPIAN BUilDING CODE STANDARDSECfION 22DIAGNOSTIC IMAGING INSTALLATION22.1 SCOPE(1) This Section of the Code applies to the installationof x-ray and other diagnosticimagingequipmentoperatingat anyfrequency.However, it does not specifysafeguardsagainstdirect, stray,or secondaryradiationemittedby the equipment.22.2 NORMATIVE REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationof Buildings:a) C22.1:1990b) NFPA70/NEC:198622.3 DEFINITIONSCanadianElectricalCode,Part1,SafetyStandardfor ElectricalInstallations,SixteenthEdition.National Fire Protection Association!American NationalElectricalCode,1987Edition.(1) For thepurposeof thisSection,in additionto thetermsdefinedin Section1,thefollowingdefinitionsshallapplywhenreferringto x-rayor computerizedtomographyequipment,long-timeratingmomentaryratinga ratingthatis applicablefor anoperatingperiodof5.0min or more.a ratingthatis applicablefor an operatingperiodof notmorethan20.0s.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 405ELECTRICAL INSTALLATION OF BUILDINGS22.4 mGH-VOLTAGE GUARDING(1) High-voltagepartsshallbemountedwithinmetalenclosuresthatarebondedtoeaithexceptwheninstalledin separateroomsor enclosureswherea suitableswitchshallbe:a) providedto controlthecircuitsupplyingdiagnosticimagingequipment,andb) arrangedso thatit will be in an openpositionexceptwhenthedoor of theroom orenclosureis locked.(2) High voltagepartsof diagnosticimagingequipmentshallbe insulatedfromtheenclosure.(3) Conductorsin thehighvoltagecircuitsshallbeof theshock-prooftype.(4) A milliammetre,if provided,shallbe:a) connected,if practicable,in theleadthatis bondedto earth;'orb) guardedif connectedin thehighvoltagelead.22.5 CONNECTIONS TO SUPPLY CmCUIT(1) Permanentlyconnecteddiagnosticimagingequipmentshall be connectedto the powersourceby meansof awiring methodmeetingthegeneralrequirementsof thisCodeexceptthatequipmentproperlysuppliedby a bran~hcircuitratedatnotover30.0A shallbepermittedtobe suppliedthrougha suitableattachmentplugandhard-servicecableor cord.(2) Mobilediagnosticimagingequipmentof anycapacitymaybeconnectedto itspowersourceby,suitabletemporaryconnectionsandhard-usagecableor cord.22.6 DISCONNECTING MEANS. (1) A disconnectingmeansof adequatecapacityfor at least50%of theinputrequiredfor themomentaryrating or 100% of the input requiredfor the long-timerating of x-ray orcomputerizedtomographyequipment,whicheveris greater,shall be providedin the supplycircuit in a locationreadilyaccessiblefromtheradiationcontrol.406 EBCS-10 1995 ETHIOPIAN BUILDiNG CODE STANDARDSECTION 22: DIAGNOSTIC IMAGING INSTALLATION22.7 TRANSFORMERS AND CAPACITORS(1) Capacitorsfonning part of a diagnosticimagingequipmentshall be providedwith anautomaticmeansfor dischargingandgrounding11leplateswheneverthetransformerprimaryisdisconnectedfromthesourceof supplyunlessall current-carryingpartsof thecapacitorsandofthe.conductorsconnectedtherewithare:a) at least2.5mfromthefloor and.areinaccessibleto unauthorizedpersons,orb) within metalenclosuresthat are bondedto earthor within enclosuresof insulatingmaterialif within 2.5mof thefloor.22.8 CONTROL(1) For stationaryequipment,the low-voltagecircuitof thestep-uptransfonnershallcontainanovercurrentdevicewhich:a) hasno exposedlive parts,b) protectstheradiographiccircuitagainstfaultconditionsunderall operatingconditions,andc) is installedaspartof theequipmentor adjacentthereto.(2) Whereas in (I) above,the designof the step-uptransfonneris suchthatbranchfuseshavinga currentrating lower thanthat of the overcurrentdevicearerequiredfor adequateprotectionfor fluoroscopicandtherapeuticcircuits,theyshallbe addedfor theprotectionofthesecircuits.(3) For portableequipment,the requirementsof (I) and (2) aboveshall apply; but, theovercurrentdeviceshallbelocatedin or ontheequipmentexceptthatnocurrent-limitingdeviceis requiredwhenthehigh-voltagepartsarewithinasinglemetalenclosurethatis providedwitha meansfor bondingto earth.(4) Wheremorethanonepieceof equipmentis operated'fromthesamehigh-voltagecircuit,eachpieceor groupof equipment,asa unit, shallbeprovidedwith a high-voltageswitchorequivalentdisconnectingmeans.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 407ELECTRlCAL INSTALLATION OF BUILDINGS22.9 AMPACITY OF SUPPLY CONDUcrORS AND RATING OF OVERCURRENTPROTECTION(1) Theampacityof supplyconductorsandtheratingof overcurrentprotectiondevicesshallnotbe lessthan:a) the long-timecurrentratingof x-rayor computerizedtomographyequipment,orb) 50% of the maximummomentarycurrentratingrequiredby x-ray or computerizedtomographyequipmenton a radiographicsetting.(2) Theampacityof conductorsandtheratingof overcurrentprotectiondevicesfortwoormorebranchcircuitssupplyingx~rayor computerizedtomographyunitsshallnotbe lessthan:a) thesumof the long-timecurrentratingof all x-rayor computerizedtomographyunitswhichareintendedto beoperatedatanyonetime,orb) the sum of SO% the mliximummomentarycurrentratingfor x-ray or ,computerizedtomographyequipmenton a radiographicsettingfor thetwo largestunitsplus20% ofthemaximumcurrentratingof theotherunits.22.10 .BONDING(1) Non-current-carryingpartsof tubestands,tablesandotherapparatusshallbe bondedtoearthin accordancewith therequirementsof PartI' Section7 of thisCode.408 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 23ELECTRICAL COMMUNICATIONSYSTEMS23.1 SCOPE(1) This Section appliesto the installationof electricalcommunicationsystemsincludinginfonnationprocessingsystems.23.2 NORMATIVE REFERENCE(1) The followingreferencecorttainsprovisionswhich,throughreferenceInthistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings:.23.3.1Circuitsin CommunicationCablesa) C221:199023.3 GENERALCanadian Electrical Code Part 1, Safety Standardfor ElectricalInstallations,Sixteenth:'Edition.(i) Radio andtelevisioncircuits,remotecontrolcircuits,fire alarmcircuits,or partsthereofshallbe:a) pennittedto useconductorsin a cableassemblyof communicationbuildingentrancehavingotherconductorsusedascommunicationcircuits,b) deemedto becommunicationcir.cuitswithintheportionsof circuitsthatuseconductorswithin thecommunicationbuildingentrancecableassembly,andc) suitablyprotectedat thepoint of interfaceconnectionwith thecommunicationcableconductors.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 409ELECTRICAL INSTALLATION OF BUILDINGS23.3.2HazardousLocations(1) Wherethewiring or electricalequipmentwithinthe scopeof this Section'is installedinhazardouslocationsasdefinedin SectionsII, 12,or 14,it shallalsocomplywiththeapplicableClausesof thoseSections.23.3.3ApprovedTransformers(1) Wheretransformersor otherdevicessupplYcurrentto a communicationcircuit from an -electric'supplycircuit,thetransformersor otherdevicesshallbe of a typeapprovedfor theservice.23.4 INSIDE CONDUCTORS23.4.1,ConductorsArrangement(1),Conductorsshallbeneatlyarrangedand'securedin placein a'convenientandworkmanlikemanner.(2) Racewaysfor communicationcircuitsihallbeinstalledin accordancewiththerequirementsof Section10and,in caseof metal,theyshallbeearthedin accordancewiththeprovisions'ofSection7.23.4.2Insulation(1) Wire andcableusedfor communicationsystemin abuildingshallbeof theapprovedtypesas specifiedin Annex B, Section4 of thisStandard.j 23.4.3EarthingConductorswithanOuterMetalCoveringv(1) Whereaconductoror cableis equippedwithanoutermetalcovering,thecoveringshallbeearthed.23.4.4SeparationfromOtherConductors(1) Theconductorsof anelectricalcommunicationsysteminbuildingsshallbeseparatedatleast50.0mmfromanyinsulatedconductorof a Class1circuitor anelectriclightor powersystem410 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD23.4.6CommunicationCablein Boistways23.4.5Penetrationof a Fire Separation(1) Specialpermissionshallberequiredto installcommunicationconductorsin hoistways.EBCS-10 1995 411TANDARDETHIOPIAN BUILDING CODa) theconductorsof all systemsareinsulatedandareseparatedby at least50.0mm,orb) theconductorsof eithersystemareencasedin noncombustibletubing.a) thecommunicationconductorsareseparatedfromtheotherconductorsby anacceptablepartition,orb) thepoweror Class1 conductorsareplacedsolelyfor thepurposeof supplyingpowerto thecommunicationsystem,or for connectionto remotecontrolequipment.a) one systemis in earthedmetalraceways,metalsheathedcable,or earthedarmouredcable,'b) theClass1 circuitor electriclightor powersystemoperatingat380.0Vor lessutilizesa nonmetallicsheathedcableor hard~llsageor extra-hard-usageflexiblecord,orc) bothsystemsarepermanentlyseparatedbyacontinuous,firmly fixednon-meta!racewayin additionto theinsulationof theconductors.SECTION 23: ELECTRICAL COMMUNICATJON SYSTEMSoperatingat 380.0V or less,and shall be separatedat least600.0mm.from any insulatedconductoror anelectriclightor powersystemoperatingatmorethan380.0Vunless:(1) Conductorsof communicationcircuitsextendingthrougha fire separationshallbeinstalledso asto limit thespreadof fire.(4) The conductorsof anelectricalcommunicationsystemin a buildingshallnotbeplacedina shaftwith theconductorsof anelectriclightor powersystemunless:(2) Wherethe light or powerconductorsarebare,all communicationconductorsin thesameroomor spaceshallbeenclosedin anearthedmetalracewayandno opening,suchasanoutletbox, maybe locatedwithin 2.0mof bareconductorsof upto andincluding15.0kVoLwithin3.0mof bareconductorsabove15.0kV.(3) Theconductorsof anelectricalcommunicationsystemshallnotbeplacedin anyoutletbox,junction box,raceway,or similarfittingor compartmentwhichcontainsconductorsof electriclight or powersystemsor of Class I circuits(asdefinedin Section10)unless:ELECTRICAL INSTALLATION OF BUILDINGS(2) All conductors,excepttravellingcables,shall be totally enclosedin continuousmetalraceway.(3) Pullboxesrequiredfor communicationinterconnectionshallbelocatedoutsidethehoistway.23.4.7CommunicationConductorsin DuctsandPlenumChambers(1) Communicationconductorsshallnot be placedin ductsor plenumchambersexceptaspermittedby relevantClausesof Section8.23.4.8DataProcessingSystems(1) The interconnecting'cablesusedin dataprocessingsystemsshallbe permittedto eontainpower and communicationconductorswhereSU9hcablesare specificallyapprovedfor thepurpose.23.4.9ConductorSunderRaisedFloon(1) Conductorsor communicationcircuitsshallbeallowedto be installed,withoutadditionalmechanicalprotection,undera raisedfloor providedthat:a) theraisedfloor is of suitablenoncombustibleconstruction;b) at leastaSO.Ommseparationis providedandmaintainedwheretheconductor,sareusedto servedataprocessingsystemsand areplacedparallelto any otherpower supplywiring; andc) the conductorsservetheequipmentlocatedonly on thefloor abovethe raisedfloor,wherethespaceundertheraisedfloor is usedasanair plenum.23.4.10 Conductorsin ConcealedInstallations(1) Wheretheendsof cablesor conductorsarenotterminatedonadevice,theyshallbecappedor taped.412 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 23: ELECTRICAL COMMUNICATION SYSTEMS23.4.11 TypeCFC Under-CarpetWiringSystem23.4.11.1General(1) Theprovisionsof Clause23.4.11apply totheinstallationof communicationflat-cable-type(CFC) systemswhich,togetherwiththeconnectingdevices,shallbeapprovedor acceptableforthepurpose.23.4.11.2Usepermitted(1) Type CFC systemwiring shallbepermittedto beused:a) only undercarpetsquaresnot exceeding7S0.0mm,andanyadhesiveusedshallbe ofreleasetype;b) asanextensionQf conventionalwiring to serveareasor zones,andeachrunof wiringfrom thetransitionpoint~all notexceedIS.0m;c) on hard, smooth,continuousfloor surfacemadeof concreteif sealed,ceramicorcompositionflooring,wood,or similarmaterial;d) in dry or interiordamplocations;e) on floorsheatedin excessof 30Conly,if approvedandidentifiedfor thatpurpose.23.4.11.3Useprohibited(1) Type CFC systemwiring shallnotbeused:a) outdoorsor in wet locations;b) wheresubjectto corrosivevapoursor liquids;c) in hazardouslocations;d) in dwellingunits;e) in hospitalsor institutionalbuildingsexceptin officeareas;t) on walls exceptwhenenteringthetransitionpoint;g) underpermanenttypepartitionsor walls.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 413ELECTRICAL INSTALLATION OF BUILDINGS23.4.11.4Floorprotectivecoverings(1) TypeCFC systemwiring shallbecoveredwith abrasionresistanttape,securedto thefloorso asto completelycoverall cables,corners,andbareconductorends.23.4.11.5Coverings(1) Type CFC systemwiring shallbepermittedtocrossoveror undereachother,andoverorunderpowersupplysystemwiring providedthereis a layerof earthedmetalshieldingbetweentheCFC andthepowersupplysyste~cables.23.4.11.6Systemheight(1) Type CFC systemwiring shallnotbe stackedon top of eachotherexceptas requiredtoenterthetransitionpoint.23.4.11.i' Earthingof shields(1) Type CFC systemwiring equippedwith.ametalshieldshallbeearthed.'23.5 EQUIPMENT23.5.1CommunicationEquipmentin Bathrooms(I) Communicationequipmentlocatedin a bathroomshallbepermanentlyfixed on thewall,andshallbe locatedso thatno partmaybereachedor usedfromthebathor fromtheshowerenclosure;however,it shallbepermittedto beactuatedby meansof a cordwith an insulatinglink. .(2) Communicationjacks shallnotbe locatedin a bathroom.23.5.2Equipmentin Air Ducts,Plenums,or SuspendedCeilings(1) Communicationequipmentandterminalsshallnotbeplacedin ducts,plenums,or hollowspaceswhich are usedto transportair nor in suspendedceilingareasexceptwherea duct,plenum,or hollow spaceis createdby a suspendedceiling having lay-in panelsor tiles;connectingblockswhichareanon-protectivetypemaybeinstalledprovidedtheyareplacedinanaccessibleenclosure.414 EBCS-10 1995--------- --- --- --- ---ETHIOPIAN BUILDING CODE STANDARDSECTION 23: ELECTRICAL COMMUNICATION SYSTEMS----------- ----,,----------------------------23.5.3ExposedEquipmentandTerminations(1) Exposedcommunicationequipmentand/orassociatedterminationsshall be locatedin asuitableroom separatefrom electricallight or powerinstallations,exceptwherenecessarytoplacethemin ajoint-useroomin whichcaseaminimumseparationof 900.0mmfromelectricalequipmentrequiringadjustmentandmaintenanceshallbeprovidedandmaintained.23.5.4Earth Circuits(1) Communicationcircuitsconnectedtoatelecommunicationnetworkandhavingreturnpathvia local earthor othercircuitrywhichsimilarlycouldpresenta fire hazard,shallbeprovidedwith a current-limitingdeviceinstalledin or adjacentto theequipmentof a typerecommendedbytheequipmentmanufacturerassuitablefor theapplication,whichwill limit thecurrentundernormaloperatingconditionsandunderfaultconditions,to preventfire hazards.23.5.5CommunicationSystemsin Hospitals(1) Exposed non-current-carryingmetal parts, if they could become energized, ofcommunicationsequipment,otherthantelephonesets,installedin general,intermediate,andcritical care areas of hospitalsshall be earthedto conform with the requirementsofClause14.4.2(5).23.6 OUTSIDE CONDUCTORS23.6.1OverheadConductorsonPoles(1) The installationof overheadcommunicationconductorson polesin proximitywith powerconductorsshall be establishedin conformitywith therulesandregulationsof the EthiopianElectricLight & PowerAuthority(EELP A.).23.6.2OverheadConductorsonRoofs(1) Communicationconductorspassingoverbuildingsshallbekeptatleast2.5maboveanyroofwhichmayreadilybewalkedupon.(2) Communicationconductorsshallnot beattachedto theuppersurfacesof roofs or berunwithin 2.0m,measuredvertically,of a roof withoutspecialpermission.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 415ELECTRICAL INSTALLATION OF BUILDINGS23.6.3LightningConductors(1) Separationof atleast2.0mshall,wherepracticable,bemaintainedbetweenconductorsofcommunicationcircuitson buildingsandlightningconductors.23.6.4SwimmingPools(1) Wherewiresor cablesareinstalledoveror adjacenttoswimmingpools,theyshallbepacedin accordancewith theprovisionsof Clauses25.4.2and25.4.3of Section25.23.7 UNDERGROUND CIRCUITS23.7.1DirectBuriedSystems(1) Where communicationconductorsor cableassembliesaredirectburied,thesheathshallbesuitablefor directburialandtheconductoror cableassemblyshall:a) notbe installedin thesameverticalplanewithotherundergroundsystems,exceptwheninstalledin accordancewith (g) below;b) maintainaminimumhorizontalseparationof300.0mmfromotherundergroundsystem's,exceptwheninstalledin accordancewith (g) below;c) notbe lessthan600.0mmdeep,unlessrockbottomis encounteredata shallowerdepthin whichcasea minimumdepthof 450.0mmshallbepermitted,exceptthatfor servicewire underparkwaysandlawns,thedepthmaybereducedto 450.0mm;d) beplacedwitha layerof sand75.0mmdeep,bothaboveandbelowthecable,if in rockyor stonyground;e) notbe lessthan900.0mmdeepunderanareawhichis subjecttovehiculartraffic,exceptthatthe depthmay be reducedto 600.0mmwhenmechanicalprotectionis provided,whichshallconsistof:i) treatedplankatleast38.0mmthickor otheracceptablematerialwhichshallbeplacedover the conductoror cableafterfirst backfillingwith 75.0mmof sandor earthcontainingno rocksor stones,orii) a conduitsuitablefor earthburial placedto facilitatecable replacementand tominimizetrafficvibrationdamage;416 EBCS-10 1995 ET:..jIOPIANBUILDING CODE STANDARDSECTION 23: ELECTRICAL COMMUNICATION SYSTEMSf) notbeplacedin acommontrenchinvolvingrandomseparationwithpowersupplycablesor wiresoperatingatover750.0Y;andg) haveametalsheathwhenplacedin acommontrenchinvolvingrandomseparationwithpower supply cablesor wiring operatingat 750.0Y or less, in which case thecommunicationconductoror cableassemblyshallnotcrossunderthesupplycable~,.23.7.2UndergroundRaceway(1) Wherecommunicationconductorsor cableassembliesareplacedin undergroundracewaysystems:a) theraceway,includinglaterals,shallbeseparatedfromthoseusedfor theelectricpowersystemby not less[han50.0mmof concreteor 300.0mmof well-tampedearth;b) theracewayshallbe locatedto maintainminimumdepthof 600.0mmin areassubjectto vehiculartraffic and.450.0mmin all otherareas,exceptthatwhererock bottomisencounteredata shallowerdepth,theracewayshallbeencasedin concrete;c) the racewayshall not terminatein the samemanhole,and the conductorsor cableassemblyshallnotbeplacedin thesamemanholeusedfor electricpowersystem;d) thecablesshallnotbeplacedin thesameracewaycontainingelectriclightingor powersupplycables;ande) thecablesheathshallbesuitablefor wet locations.23.8 EARTHING23.8.1Bon~ingof CableSheath(1) Wherecables,eitheroverheador underground,enterbuildings,themetalsheathor shieldof thecableshallbebondedto earthascloseaspracticableto thepointof entranceor shallbeinterruptedascloseaspracticableto thepointof entranceby an insulatingjoint or equivalentdevice.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 417ELECTRICAL INSTALLATION OF BUILDINGS23.8.2Cable-SheathBondingConductor(1) Thecable-sheathbondingconductorrequiredbyClause23.8.1shallhaveanampacityequalto or greaterthanthatof the outerconductivesheathof the exposedcableexceptthatthebondingconductorshallnotberequiredto belargerthan10.0mm2copper.23.8.3EarthingElectrode(1) Earthingconductorshallpreferablybeconnectedtoawater-pipeearthingelectrodeascloseto thepointof entranceaspossible.(2) Where waterpipeis not readily availableand the earthingconductorof the powerconsumer'sserviceis connectedto thewaterpipeat thebuilding,thecommunicationsystemearthingconductormaybeconnectedto themetalconduit,serviceequipmentenclosures,or totheearthingcond~ctorof thepowerconsumer'sservice.(3) In theabsenceof a waterpipe,thecommunicationearthingconductormaybeconnectedtoaneffectivelyearthedmetalstructureor to'anearthrod or pipedriveninto.permanentlydampearth;but:a) steam,gas,or hotwaterpipesor lightningrod conductorsshallnotbeusedasearthingelectrodes;andb) a driven rod or pipe used for earthingpower circuits shall not be used as acommunicationearthingelectrodeunlessit is connectedto theearthedconductorof amulti-earthedpowerneutral.(4) Where a driven earthrod or pipe is usedas an earthingelectrodefor an electricalcommunicationsystem,it shall be separatedby at least2.0m from any other electrodes,includingthoseusedfor powercircuits,radio,lightningrods,or for anyotherpurposeandshallbe bondedonly tothatof thepowercircuitsin accordancewithapplicableClausesof Section7.(5) The normallengthof drivenearthrod usedastheearthingelectrodefor a communicationsystemis 1.5m;but,wherethenormalrodwouldnot reachmoistsoil wheninstalled,a rodofsuitableadditionallengthshallbeused.418 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 23: ELECTRICAL COMMUNICATION SYSTEMS23.8.4EarthingElectrodeConnection(1) The earthingconductorshallbeattachedto anearthingelectrodeby meansof anapprovedbolt clampexceptthat,in thecaseof anearthrod, awire leadmaybepermanentlyconnectedto therod.(2) Whereaboltclampisused,theearthingconductorshallbesolderedor otherwiseacceptablyconnectedto theclampin aneffectivemanner.23.8.5Bondingof Electrodes(1) A copperconductornotsmallerthan10.0mm2shallbeconnectedbetweencommunicationand power earthingelectrodeswhen separateartificial earthingelectrodesare requiredasdescribedperClause23.8.3.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 419SECTION 24CO:MMUNITY ANTENNA INSTALLATIONFOR RADIO AND TELEVISIONRECEPTION24.1. SCOPE(1) This Sectionappliesto theinstallationof:a) communityantennaassembly,b) headstation(amplifierandotherpowersources),andc) distributionnetwork(conductors,branchingboxesandantennaor feederoutlets),24.2 NORMATIVE REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings:a) C22.1:1990b) lEC 597i) Part 1-1977,ii) Part2-1977iii) Part 3-1983iv) Part4-1984CanadianelectricalCode, Part 1, Safety Standardfor ElectricalInstallations,SixteenthEdition.Aerials for theReceptionof SoundandTelevisionBroadcastingintheFrequencyRange30.0MHZto 1.0GHZ:Electricalandmechanicalcharacteristics.Methodsof measurementof electricalperformanceparameters.Methodsof measurementof mechanicalproperties,vibration andenvironmentaltests.Guideforthepreparationof aerialperformancespecification,detailedspecificationsheetformat.420 EBCS~10 1995 ETHIOPIAN BUILDING CODE STANDARD-.- -c) IEC 728:1982SECTION 24: COMMUNITY ANTENNA INSTALLATIONCabled Distribution SystemPrimarily Intended for Sound andTelevisionSignalsOperatingbetween30.0MHzand 1.0GHz.24.3 TECHNICAL REQUIREMENTS24.3.1Mechanical(1) A communityantennashallcomplywith'all mechanicalpropertiesor requirementsoutlinedin theIEC 597andIEC 728.24.3.2Electrical(1) A communityantennashall:a) bedesi.gnedfor thereceptionof signalswithinthepermittedbandwidthfor soundandtelevisionbroadcasting;b) be immuneto extraneoussignalinterference;andc) complywithall ethernecessaryelectricalparametersthatarerequiredforthesatisfactoryoperationof thesystem(seeIEC 597andIEC 728).24.4 EQUIPMENT24.4.1CommunityAntennaDistributionAmplifiersandOtherPowerSources(1) Amplifiers andotherdeviceswhich supplycurrentto a communityantennadistributioncircuit from anelectricsupplycircuitshallbe approvedfor thepurpose.(2) WhereliIllplifiersandotherpowerdevicesareconnectedto anelectricsupplycircuitandenclosedin a cabinet,the cabinetshallbe so.locatedas to be readilyaccessibleandshall beadequatelyventilated.(3) The chassisandcabinetsof thecommunityantennadistributionamplifieror otherpowersources,theouterconductiveshieldof thecoaxialcables,andthemetalconduitor themetalcablesheathenclosingtheelectricsupplyconductorsshallall beconnectedto thesystemearthwith a minimumof 16.0m2copperconductor.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 421ELECTRICAL INSTALLATION OF BUILDINGS(4) Whereacabinetcontaininganamplifierorotherpowerdeviceis mountedaccessibleto thepublic, it shallbeprovidedwith a lock or similarclosingdevice.24.4.2 EXDosedEquipment and Terminations(1) Exposedcommunityantennadistributionequipmentand/orassociatedterminationsshallbelocatedin a suitableroomor similararea,separatefromelectricallightor powerinstallations,exceptwherenecessaryto placethemin ajoint-useroomin whichcasea minimumseparationof 900.0mmfromelectricalequipmentrequiringadjustmentandmaintenanceshallbeprovidedandmaintained.24.4.3 Equipment Earthing(1) Non-poweredequipmentandenclosuresor equipmentpoweredexclusivelyby thecoaxialcableshall be consideredearthedwhentheyareeffectivelyconnectedto the earthedouterconductivecoaxialcableshield.24.5 COMMUNITY ANTENNA DISTRIBUTION NETWORK24.5.1 Conductor(1) The conductorsusedin thedistributionnetworkshallconsistof coaxialcablehavinginnerconductorandanouterconductiveshieldof circularcross-section.(2) Conductorsplacedwithinbuildingsshallbeof theapprovedtypesasspecifiedin AnnexB,Section4, of thisCode.(3) Conductorsplacedoutsideof buildingsshallbe of thetypesthatareacceptablefor theapplication.24.5.2 VoltageLimitation(1) The coaxialcableshallbe permittedto deliverlow energypowerto equipmentdirectlyassociatedwiththecommunityantennadistributioncircuitsif thevoltageis notover60.0Vandif thecurrentsupplyis fromanapprovedamplifier,transformer,or otherdevicehavingenergylimitingcharacteristics.422 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD- - --SECTION 24: COMMUNITY ANTENNA INSTALLATION24.5.3HazardousLocations(1) Wherethecircuitsor equipmentwithinthescopeof thisSectionareinstalledin hazardouslocations,theyshallalsocomplywiththeapplicableClausesof Sections12,13and14.24.5.4Supports(1) Whereconductorsareattachedto or supportedon buildings,theattachmentor supportingfixturesshallbeacceptablefor thepurpose.24.5.5Earthingof OuterConductiveShieldof a CoaxialCable(1) Wherecoaxialcableis exposedto lightningor to accidentalcontactwith lightningarresterconductorsor power conductorsoperatingat voltageexceeding380.0V-to-earth,the outerconductiveshieldof thecoaxialcableshallbe earthedat thebuildingascloseto thepointofcableentryaspossible.(2) Wheretheouterconductiveshieldof a coaxialcableis earthed,nootherprotectivedeviceshallberequired.(3) Earthingof a coaxialcableshieldby meansof a protectivedeviceshall be permitted -,providedthatthedevicedoesnot interrupttheearthingsystemwithinthebuilding.24.5.6EarthingConductor(I) The earthingconductorfor theouterconductiveshieldof acoaxialcableshallhaverubberinsulationnot lessthan O.8mmin thickness,and shall be coveredby a substantialfibrouscoveringexceptthatconductorsacceptablefor the purpose,havinglessthanO.8mmrubberinsulation,or havingotherkindsof insulation,maybeused.(2) The earthingconductorshallbeof copper.(3) The earthingconductorsshallbenotsmallerthan2.5mm2(4) The earthingconductorshallhaveanampacityequalto or greaterthanthatof theouterconductivesheathof theexposedcoaxialcable.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 423ELECTfilCAL INSTALLATION OF BUILDINGS(5) Wheretwoor morecoaxialcables,whichhaveouterconductiveshieldsdifferingin sizeandampacity,join ata commonconnectionto theearthingconductor,theampacityof theearthingconductorshallbeequaltoor exceedtheampacityof thelargestcoaxialouterconductiveshield.(6) The earthingconductorshallberun fromthecoaxialcableshieldto theearthingelectrodein as straighta line aspossible.(7) The earthingconductorshallbe protectedin situationswhereit is or canbe exposedtomechanicaldamage.24.5.7 Earthing Electrode(1) Earthingelectrodesshallconformto therequirementsof relevantClausesof Section7.(2) Whereartificialearthingelectrodesareinstalled,theyshallbein accordancewithapplicableClausesof Section7 exceptthattheminimumdrivenlengthof therod electrodeshallbe2.0m.(3) Artificial earthingelectrodesfor communityantennadistributionshallbespacedandbondedwith otherelectrodesin accordancewith relevantClauseof Section7.24.5.8 Earthing ElectrodeConnection(1) Theearthingconductorshallbeattachedto anearthingelectrodeby meansof.anapprovedearthclampexcept,in thecaseof anearthrod, awire leadmaybepermanentlyconnectedtotherod andthewire leadconnectedto theearthingconductorby meansof pressureconnectoror otheracceptablemeans.(2) Whereanearthclampis used,theearthingconductorshallbeacceptablyconnectedto theclampin aneffectivemanner.24.6 CONDUCTORS WITHIN BUILDINGS24.6.1 Separationfrom Other Conductors(1) Conductorsof communityantennadistributioncircuitsshallbeseparatedat least50.0mmfrom insulatedconductorsof electriclighting,power,or Class1circuitsoperatingat380.0Vorless,and shall be separatedat least600.0mmfrom any insulatedconductorof an electric424 EBCS-10 1995 ETHIOpiAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONlighting,power,or Class1circuitoperatingatmorethan380.0Vunlesseffectiveseparationisaffordedby useof:a) earthingmetalracewaysfor the communityantennadistributioncircuits,or for theelectriclighting,powerandClassI circuits,b) earthedmetalsheathedor armouredcablefor theelectriclighting,power,andClass1conductors,c) nonmetallicsheathedcablefor theelectriclighting,power,andClass1circuitsoperatingat380.0Vor less,ord) racewaysof a non-metaltypeaspermittedin Sectio~8in additionto theinsulationonthecommunityantennadistributioncircuitconductors,ortheelectriclightingpower,andClass I circuitconductors.(2) Wheretheelectriclightingorpowerconductorsarebare,all communityantennadistributionconductorsin the sameroomor spaceshallbe enclosedin an earthedmetalracewayandnoopening,suchasan outletbox, shallbe locatedwithin 2.0mof bareconductorsof up to andincluding15.0kVor within 3.0mof bareconductorsabove15.0kV.(3) The conductorsof a communityantenna:distributioncircuit shall not be placedin anyraceway,compartment,outletbox,junctionbox,or similarfittingwhichcontainsconductorsofelectriclight,power,or ClassI circuitunless:a) the conductorsof the communityantennadistributioncircuitare separatedfrom theelectriclight,power,or Class I circuitconductorsby anacceptablebarrier,orb) thepoweror Class I conductorsareplacedsolelyfor thepurposeof supplyingpowerto thecommunityantennadistributioncircuit.24.6.2 Conductors in a Vertical Shaft(1) Conductorsof a communityantennadistributioncircuit in a verticalshaftshallbe in atotallyenclosednoncombustibleraceway.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 425ELECTRICAL INSTALLATION OF BUILDINGS24.6.3Penetrationof a Fire Separation(1) Conductorsof a communityantennadistributioncircuitextendingthroughfire separationshallbe so installedasto limit fire spread.24.6.4CommunityAntennaDistributionConductorsin DuctsandPlenumChambers(1) Communityantennadistributionconductorsshallnotbeplacedinductsorplenumchambersexceptaspermittedby relevantClausesof Section2 andSection8 of thisCode.24.6.5Raceways(1) Racewaysshallbe installedin accordancewiththerequirementsof Section8024.7 CONDUCTORS OUTSIDE OF BUILDINGS24.7.1OverheadConductorsonPoles(1) The installationof overheadcommunityantennadistributionconductorsin proximitywithpowerconductorson polesandin aerialspansbetweenbuildings,poles,andotherstructuresshallbe establishedin conformitywith rulesandregulationsof EELP A .24.7.2OverheadConductorsonRoofs(1) Communityantennadistributionconductorspassingoverbuildingsshallbe keptat least205maboveanyroof whichmaybereadilywalkedupon.(2) Communityantennadistributionconductorsshallnotbeattachedto theuppersurfacesofroofsor berun within205m,measuredvertically,of a roof withoutspecialpermission.24.7.3ConductorsonBuildings(1) Communityantennadistributionconductorsonbuildingsshallbeseparatedfrom insulatedlightor powerconductorsnotin cableor conduitby atleast300.0mmunless,in additionto theinsulationon theconductors,theyarepermanentlyseparatedby a continuousandfirmly fixednon-metaltyperacewayaspermittedin Section8 0426 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLAT10N(2) Communityantennadistributionconductorssubjecttoaccidentalcontactwith lightor powerconductorsoperatingatvoltagesexceeding380.0Vandattachedexposedto buildingsshallbeseparatedfromcombustiblematerialby beingsupportedonglass,porcelain,or otherinsulatingmaterialacceptablefor thepurpose,exceptthatsuchseparationis notrequiredwheretheouterconductivesheathof thecoaxialcableis earthed.(3) Communityantennadistributionconductorsattachedto buildingsshall not conflictwithothercommunicationconductorsattachedto thesamebuildingandsufficientclearanceshallbeprovidedsothattherewill notbeunnecessaryinterferencetomaintenanceoperations;andin nocaseshouldtheconductors,strand,orequipmentof onesystemcauseabrasionto theconductors,strand,or equipmentof theothersystem.24.7.4ConductorsEnteringBuildings(1) The communityantennadistributionconductorsshallenterthebuildingeitherthwugh anoncombustible,non-absorptiveinsulatingbushingor througha metalracewayexceptthattheinsulatingbushingor racewaymay be omittedwherethe enteringconductorspassthroughmasonryor areacceptablefor thepurpose.24.7.5SwimmingPools(1) Whereconductorsareinstalledoveror adjacentto swimmingpools,theyshallbeplacedinaccordancewith theprovisionsof Clauses25.4.2and25.4.3,Section25of thisCode.24.8 UNDERGROUND CONDUCTORS24.8.1DirectBuriedSystems(1) Wherecommunityantennadistributionconductorsaredirectburied,the sheathshallbesuitablefor directburialandtheconductorshallbe:a) installedoutsideof the samevertical planewhich containsdiffering undergroundconductorsotherthancommunicationconductors,exceptwheninstalledin accordancewith (f) below;b) maimtainedataminimumhorizontalseparationof 300.0mmfromdifferingundergroundconductorsotherthancommunicationconductors,exceptwheninstalledin accordancewith paragraph(f) below;ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 427ELECTRICAL INSTALLATION OF BUILDINGSc) placedat a minimumdepthof 600.0mm,unlessrock bottomis encounteredat ashallowerdepth,inwhichcaseaminimumdepthof 450.0mmshallbepermitted,exceptthatfor servicewiresunderparkwaysandlawns,thedepthmaybereducedto450.0mm;d) placedwith a layerof sand75.0mmdeep,bothaboveandbelowthecable,if in rockyor stonyground;e) placedat a minimumdepthof 900.0mmunderan areawhich is subjectto vehiculartraffic,exceptthatthedepthmaybereducedto 600.0mmwhenmechanicalprotectionis providedwhichshallconsistof:i) treatedplankatleast38.0mmthickorotheracceptablematerialwhichshallbeplaced~verthe conductoror cableafterfirst back-fillingwith 75.0mmof sandor earthcontainingno rocksor stones;orii) a conduitsuitablefor earthburial placedto facilitatecable replacementand tominimizetrafficvibrationdamage;andf) equippedwith a metal shieldwhen placedin a commontrenchinvolving randomseparationwithpowersupplycablesorwiringoperatingat750.0Vor less,in whichcasethecommunityantennadistributionconductorsshallnotcrossunderthe supplycables24.8.2UndergroundRaceway(1) Where communityantennadistributionconductorsare placedin undergroundracewaysystems:a) the raceway,includingmaterials,shall be separatedfrom thoseusedfor the electricpowersystemby not lessthan50.0mmof concreteor 300.0mmof well-ta!T';,r..l-.alth;b) theracewayshallbe locatedto maintaina minimumdepthof 600.0mmin areassubjectto vehiculartraffic and450.0mmin all otherareasexceptthat,whererock bottomitencounteredat shallowerdepth,theracewayshallbeencasedin concrete;c) the racewayshall not terminatein the samemanholeand the conductorsor cableassemblyshallnotbeplacedin thesamemanhole,usedfor electricpowersystem,d) the conductorsshallnot be placedin the sameracewaycontainingelectriclighting,poweror Class1 circuitconductors;ande) thecablesheathshallbesuitablefor wetlocations.428 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANC,ARDSECTION 24: COMMUNITY ANTENNA INSTALLATION24.8.3UndergroundBlockDistribution(1) Wheretheentirestreetcircuitis runundergroundandthecircuitis placedso.thatit is notliableto be in contactwith electriclighting,power,or Class1 circuitsof morethan380.0V,insulatingbushingsor racewaysshall not be requiredwherethe circuit conductorsenterabuilding.24.9 LIGHTNING ARRESTERS FOR RECEIVING STATIONS24.9.1LightningArrester(1) A lightningarrestershall:a) be providedfor eachlead-inconductorfromanoutdoorantennato a receivingstatio~exceptwheresuchlead-inconductoris protectedby a continuousearthedmetalshieldbetweentheantennaandthepointof entranceto thebuilding;b) be locatedoutsidethebuildingor insidethebuildingbetweenthepointof entranceorthelead-inandtheradiosetor transformer,andasnearaspracticableto theentrancetotheconductorsto thebuilding;andc) notbe locatednearcombustiblematerialnor in a hazardouslocation.24.9.2 EarthingConductor24.9.2.1 Material(1) The earthingconductorshallbeof copper,aluminiumalloy,copper-cladsteel,bronze,orothercorrosion-resistantmaterialunlessotherwisespecified.24.9.2.2 Insulation(1) The earthingconductormaybeuninsulated.24.9.2.3 Support(1) The earthingconductorshallbesecurelyfastenedin placeandmaybedirectlyattachedtothesupportingsurfacewithouttheuseof insulatingsupports.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 429ELECTRICAL INSTALLATION OF BUILDINGS24.9.204Mechanicalprotection(1) The earthingconductorshallbeprotectedwhereexposedto mechanicalinjury.24.9.2.5 Earthingconductortoberun in a straightline(1) The earthingconductorshallberunin asstraighta lineasis practicablefromthelightningarrestersof antennamast,or both,to theearthingelectrode.24.9.3 EarthingElectrode24.9.3.1 Earthingelectrode(1) Theearthingconductorshallbeconnectedtoanearthingelectrodeasspecifiedin Section7.24.9~3.2Earthingconductors(1) The earthingconductormayberuneitherinsideor outsidethebuilding.24.9.3.3 Sizeofprotectiveearth(1) The sizeof protectiveearthingconductorfor receivingstationsprovidingearthconnectionfor mastandlightningarrestersshallbe in accordancewiththeprovisionsof Section7.24.9.3.4 Commonearth(1) A singleearthingconductormaybeusedfor bothprotectiveandoperatingpurposes;butitmustbe installedso thatdisconnectionof theoperatingearthwill not be aftertheprotectiveearthcircuit._______430 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDA.I.1 IntroductionA.I GENERAL..EBCS-10 1995 431antennainstallationsthatsupplyradioandtelevisionsignalstohouseholdsin one or more buildings.They consistsof anantennaassembly,a head station(amplifier unit) and thedistributionnetwork including the cables, branch-inunits,antennasocketsandthe associatedreceiverconnectioncables(seeFigureA.3).antennainstallationsthatsupplyradioandtelevisionsignalstoa singlehousehold. Modern householdare providedwith anumberof antennasockets.To makeanadequatesignallevelavailableat eachsocket,amplifiersmay also be requiredinsomeindividualantennainstallations(seeFigureA.I).It is usualnowadaysto install communityaerial systemsinapartmentbuildings.They areconsiderablymoresatisfactorythan large numberof individual antennasbecausemutualinterferenceis eliminatedandthemostsuitablepositionon theroof canbechosenfor theantenna.ANNEX A (INFORMATIVE)ANTENNA (AERIAL) SYSTEMStt SeeSiemens'ElectricalInstallationHandbook,Part3, 1979,Siemens.ETHIOPIAN BUILDING CODE STANDARDAn efficient antennainstallationis oneof theprerequisitesfor interference-freereceptionofradioandtelevisiontransmission.This canbeexpectedto performsatisfactorilyonly if it hasbeencompetentlydesingedandconstructed.A.I.2 TerminologycommunityantennasystemindividualantennaELECTRICAL INSTALLATION OF BUILDINGSprivatewide-bandsystem a specialfonn of the communityantennainstallation. Thesignalsto bereceivedarefedto theprivatewide-bandsystemfroma primarycablenetwork(seeFigureA.2).A.1.3 RegulationandSpecificationBroadcastreceivingantennainstallationsmustcomplywiththerequirementsandregulationsofthe EthiopianTelecommunicationAuthority,if any,or shallmeetthetechnicalrequirementsoutlinedin anyapplicableinternationalstandard.A.2 PLANNINGBeforetheplanningof a system,isstarted,anaccuratesurveyof thesiteshouldbecarriedout.In theprocess,thefollowi~gdatashouldbecollectedwiththeaidof thebuildingplans9r fromthedirectobservation:Numberandpositionof antennasockets- Modemantennasystemshouldbeequippedwith atleasttwo,andpreferablythreeor four,antennasocketsperapartment.Thenumberandpositionof thesocketsmustbeknownfor planningpurposes.Sound and televisionbroadcasttransmissions- The choiceof transmissionthatare worth'receivingdependson thereceptionconditions.If thesearenotknown,measurementmustbeundertakenwith a suitablesignal-strengthmeter.Position of antenna- The antennashouldbe erectedin the mostsatisfactorypositionforreceptionandbeasfar positionedaspossiblefromchimneyandpowercables.Amplifiers,frequency-convertersandpower-supplyunits- A readilyaccessiblelocationshouldbedetenninedfor theheadstationundertherof.It mustalsobeconflnnedthata connectionto the electricitysupply is available,or can be provided,close to the headunit. (see,FigureA.3)Qualityof reception- To assessthequalityof reception,it is necessaryto makemeasurementwith a suitablesignalstrengthmeter. The measurementpoint is detenninedby the antennalocationappropriateto thebuilding. If adifferentlocationis moresatisfactoryfromthepointof view of reception,it shouldbe adoptedafterconsultationwith thebuildingowneror thearchitect.432 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONA.3 DISTRIBUTION SYSTEMA.3.1 GeneralThe distributionsystembeginsattheoutputof theheadstationandendsattheantennasocketoutlets. Its purposeis to providereliabletransmissionof the signalfrom the headstationsthroughthesocketsto theradioandtelevisionreceivers.A.3.2 JunctionBoxesDistributionboxesandbranchingboxesaregenerallyreferredto by theterm'junctionboxes'.Distributionboxesareadvantageouswheremainfeedersarerunclosetogether,e.g.inapartmentblocksandhigh-risebuildings,in whichno longfeederlinesareneGessary.In longbuildingsor terracehouses,theuseof branchingboxesis moresatisfactory.Examplesof differenttypesof junctionboxesareshownin FigureA.4.A.3.3 AntennaSocketsAntennasocketoutletsaredistinguishedaccordingtotheirmodeof applicationin thedistributionnetworkandtheirtransmissioncharacteristics.Dependingontheapplication,thereareavailablethrough-wiredsockets,which are used in networkarrangedon the loop-throughprinciple(socketsfedin series,FigureAS) andspursocketswhichareintendedfor main-feedernetworksarrangedin thespur-linepattern(socketsfed in parallel,FigureA6).A.3.4 CombinedDistributionMethodIn a combineddistributionmethod,thesoundradioandtelevisionsignalsarecarriedoverthesamemainreeders. The antennasocketoutletsincorporatea socketfor thesoundradioandanotherfor thetelevision.FigureA7 showsthecombineddistributionmethodappliedtoacommunityantennasystemwiththreetelevisionchannels.FigureA8 providesasimilararrangementwithsixtelevisionchannels.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 433ELECTRICAL INSTALLATION OF BUilDINGSA.3.5 Private Wide-Band SystemPrivatewide-bandcable-networksystemssupplysubscribersondemandwithradioandtelevisiontransmissions.Thesearecomparablein termsof designto largecommunityantennasystems.The transmissionsareobtainedfrom a broadcastreceivingstationandrelayedvia cablesandamplifiersto systemconnectionpointson theperimetersof theprivateproperties.Followingthis,thereceivedsignalsareamplifiedandfedto theantennasockets(seeFigureA.9).A.4 PROTECTIONAs a protectionagainstaccidentalvoltagetransferfromtheelectricalinstallations,all inactiveconductivepartsof theantennasystem,suchastheantennapost,housings,junctionboxesandamplifiers,outerconductorsandmetallicsheathsof the antennacablesshouldbe connectedtogetherandearthed,or includedin thepotentialequalizationsystem.For potentialequalization,a permanentconnectionmustbemadebetweentheantennasystemandthemainequipotentialconductor(seeFigureA.I 0).A.5 CONSTRUCTION OF A RECEIVING-ANTENNA SYSTEMA.5.l GeneralReliableperformanceby radioandtelevisionreceiversis dependentuponthecarefulplanningandcompetentconstructionof theaerialinstallation.Informationrelativeto the lengthanddesignof theantennapostis presentedin FigureA.II andA.12.A.5.2 Length of Aerial PostThe necessarylengthandstrengthof thepostisdeterminedby thenumberandseparationof theantennas.The upperend of thetubularpostis usuallyclosedby the LF/MFIHF and USWantennas.The orderof theotherantennasis immaterialin itself. It is appropriate,however,tomounttheantennasthatpresenta highwind loadnearthebottomso longas higherplacingisnotcalledfor on groundsof efficientreception.434 EBCS-10 1995 ETHIOPIAN BUilDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONA.5.3 MinimumAntennaSeparationGuidancevaluesfor theminimumseparation'a' in centimeters,betweentheantennason thepostare given in Table A.I. The separationshouldbe increasedfor antennaswith a largernumberof elements,particularlyif theyareaimedin thesamedirection.The separationbetweenthelowestantennaunitandtheroof shouldbeat leastI.Om.TableA.I Guidancevaluesfor theminimumseparation'a' [em]betweenantennasonthespotReceptIon BandTVIUSWTV IIITVNTVVTV t2501401408080usw140110808080TV III14080808080TV IV8080806050TVV8080805050A.5.4 Wind loadandBendingMomentThe bendingmomentin thetubularantennapostis calculatedfrom:where,L is length[m] andW is windload[N].(AI)A postshouldbechosenwherepermissiblebendingmoment(fromthemanufacturer'sdata)isat leastequalto thecalculatedbendingmomentMb in Equation(AI).The capacityof thestructuralparts(buildings)to withstandtheforcesproducedin theantennainstallationshallbeverified.A.5.5 Mountingof theHeadstationThe headstationis bestmountedundertheroof in the immediatevicinityof theantennapost(FigureA13). It shouldbeensuredthata loop is formedin thecable(a watertrap)beforeitETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 435ELECTRICAL INSTALLATION OF BUILDINGSentersthe headstationto preventcondensat.efrom runningout of the tabularpost into theamplifier(FigureA.14).Attentionshouldbepaidto goodaccessibilityin considerationof subsequentmaintenance.Ifthereis no suitablewall on which to mounttheheadstation,it canbemountedon a woodenboard or fTame. Whereheadstationsare mountedin public-accessibleplacessuchas, forexample,in stairwalls,theyshouldpreferablybeaccommodatedin lockablecabinets.A.6 COMMISSIONING AND MAINTENANCEA.6.1 Measurementon CommissioningSuch measurementsshouldbe carriedout in commissioningas are necessaryto provethetechnicalperformanceof theaerialsystem.TableA.3 showsa measurementschedule,representinga communityantennasystemin tabularform, inwhichthetestpointsandtherequiredmeasurementsaredetailedandtheresultsrecord.To assesspicturequality,theassessmentsymbolsgivenin TableA.2 shouldbeenteredin themeasurementschedule.Table A.2 Assessmentgradesfor interferenceaccordingto prescribedassessmen.tcriteriaAssessment criteria Assessment gradesViewing .distanceFor commonFor reflectedAssessment ofsignalForinterferencerelativeto picturechannelinterferenceinterferenceheightinterference (G)(R)(8)aNot visible aone half GOROSO1Not visible 15 times G1R1S12Just visible 25 times G2R2S23Clearly 35 times G3R3S3visible436 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONA.6.2 Measurementof AmplifierOutputSignalLevelIn recordingthe amplifieroutputsignallevel in the headstation,the signal levelsfrom theindividualbandamplifiers(LF/MF/HF, USW, VHF, UHF) aremeasuredusinga calibratedreceiverandcomparedwith themaximumpermissibleoutputsignal levelsof the amplifiersaccordingto themanufacturers'data. In thisprocess,themanufacturer'sinstructionsfor themeasurementsandfor theproperadjustmentof theamplifiersshouldbefollowed.A.6.3 MaintenanceTrouble-freeoperationof theaerialsystemis assistedby regularcheckingof themechanicalandelectricalcomponents.The following routinechecksshouldbecarriedoutduringmaintenance:a) Aerial structure:- Orientationof aerials,- Fixing clamps,- Sealingof roof lead-in,Seatingof earthingclamps.b) Headstation:- Measurementsasfor commissioningattestpointsTPI andTP2.- The checkingandmeasurementresultsfrom eachmaintenanceoperationshouldberecordedin a suitablescheduleTableA.4 for comparisonwith othertests.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 437ELECTRICAL INSTALLATION OF BUILDINGSTableA.3 Measurementsoncommis'sioning(entriesin themeasurementsch'edule)Measurements of commissioning Recommended additional measurementsDifferenceTes between visiont-Test-pointSignal-level measurement'PictureSound qualityand sound carrierpoinposition(Values in dBI!V) qualitysignal levels int the TV channelsTPlEnd of x xxNote hum,xaerialcracking,down-leadnoise andOutput ofObserve maximum)hissTP2x xxAttenuatieachpermissible output signal onamplifier,level according to distortioconverter orcatalogue data (see nother active'lining-up' instructions) introducelectroniced byunitheadstation~2 dBTP3Output ofxLF/MF~94'the firstUSW s80receiverTV I ~84, connectingTV 11~84lead ofTV IVN~84each main or spurcableFIMFIFN5.W'!'IVTP4Ouput ofxLF/MF ~ -6 dB xthe lastrelative to reference --TPIreceiveraerial'~connectingUSW mono ~40~'TP2lead of USW stereo~SOeach mainTV I ~S2 --TP3or spurTV III ~S4cableTV IVN ~S7 --TPOx Insertappropriateentries1) For soundbroadcasttransmissions,theselectivelymeasuredcarriers:atleasttheLm,s.valuesof thelocalanddistricttransmittersin theLF, MF, HF andUSW bandsshouldbemeasured,For televisiontransmissions,thechannelsignallevels(ther,m.s,levelof thevisioncarrierat thepointwherethesynchronizingpulsesoccur)in thereceivingor distributionchannels2) Assessmentof picturequality,438 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDTableA.4 MaintenancescheduleSECTION 24: COMMUNITY ANTENNA INSTALLATIONNo.:Project: _Contract No.:No.:Street No.:Amplifier stati~~:m...._mm..m..Consumer:_______________________ __ ._. __ _no _. ~_n _. _ _. ~__ __ u __ __ wow. __ ' _.'. _Address:AmplifierDate:Name:Date:Date:Input/outputName:Name:channel lSignal levenB,ntPicture qualityaR[dB,Y][dB] [dB]TP1TP2'--f-------TP1TP2TP1TP2RG5RG5-Ch .../...Ch ...1...Ch .. ./....Ch .. ./...Ch.../...j-----t--Ch ...1...Ch .../...Ch ...1...Ch ...1...Ch.../...Ch .../...IUSW~ignalleveAssessment of sound:input/outputdB'V'.hum, chrackling, noise, hiss)channel TP1TP2LF/MF Aerial structure:Geometry,mechanicalfirmnessSeatingof earthingclampsEquipotentialbondingSealingof roof lead-inETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 439LF/MF/HF/USWaerial LF/MF/HF/USWaerial/Aerial sockelDODOa) With oneaerialsocket b) With two aerialsocketsandan amplifierFigure A.I Structure of an individual aerial installationSECTION 24: COMMUNITY ANTENNA INSTALLATION'HF widebRnd amplilier11:>Iece01previousr.eJd slallon in loll,'- :MRlndistribution, , ,system, fed Irom above'CP 10 WC nolWolkIn basement' 'b)ExistingcommunityaerialinstallationAarill structureCP Connection pointWC nelWQrk Wlde.ban~ c.ble nelw071' OllUlbuuOl tlOlla) Dinribution bOA~ror IWO, b) Br;.nchi~,bOlU furthree~ndfout m;l,in ~blC1 oneandfWD main cilbiciFigure A.4 Types and applicationsof junction boxesOi.lnbYlio-leaol..(all~ iOCAtl wilnttlITMlling;ft$ISIOf (7$OJ~~DULIOn, .DoYOI, orlnctlno bOl..11';l.rn;na1lng 'i'..I'JS C'U:Figure A.S Through-wired method Fig. A.6 Spur-line method442 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONCommunityaerial systemfor LF,MF, HF andUSW receptionand sixtelevisiontransmissionsPrivalewide;band systemFigure A.8LF/MFICh~tlFICh6 Ch21 USW eh 3~ Ch8Ch 12'ft ttt'fttIII IIIIIII IIIIIILF/MFI III IIIHFI IIIIIIIusw ~6th8C~2~I ' I'ftIIIII IIII IIII IIIFigure A.7 Communityaerialsystemfor LF MF,HF and USW receptionand threetelevisiontransmissionFigure A.9 Wide-band cablenetworkwith privatewide-bandsystemETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 443ELECTRICAL INSTALLATION OF BUILDINGSIIIIcuismm'lIIIIIIII1:1,L2:L1 - Phis.conductorsN - neultill conductorFigureA.tO Protectionof anaerialinstallationbyinclusionin theequipotentialbondingof all themetallicconductingsystemsof a buildingLF/MF/HF aenalfI a1,-I aL JIUSWaerialUHF aerialVHF~alIV,FigureA.l1 Datarelevantto the lengthof,anaerialpostFigureA.12 Datarelevanttothedesignofanaerialpost444 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 24: COMMUNITY ANTENNA INSTALLATIONFigure A.13 Recommendedarrangementof a headstationI'IRing section complelelylemovl1doV,era lenglh 015mmallhe Ipwesl point ollhe walerIrap or,shealhFigure A.14 Formation of a 'water trap'ETHIOPIAN BUILDING CODE STANDARD EBCS-1d 1995 445SECTION 25SWIMMING POOLS, FOUNTAINS ANDSIMILAR INSTALLATION25.1 SCOPE(1) This Sectionappliesto electricalinstallations,electricalequipmentin or adjacentto pools,andnon-electricalmetalaccessoriesin a pool or within3.0mof theinsidewall of a pool.Note: The tenn'pool',asreferredto in thisSection,is deemedto includepermanentlyinstalledandstorablepools,hydromassagebathtub,spasandhot tubs,waddingpools,baptismalpools,'anddecorativepools.25.2 NORMATIVE REFERENCE(1) The followingreferencecontainsprovisionswhich,throughreferencein thistext,constituteprovisionsof theEthiopianBuildingCodeStandardon ElectricalInstallationof Buildings:a) C 22.1:1990 CanadianElectricalCode,Part1,SafetyStandardElectricalInstallation,SixteenthEdition.25.3 DEFINITIONS(1) In thisSection,inadditionstothetermsdefinedin Section1,thefollowingdefinitionsshallapply:permanentlyinstalledswimmingpool a pool constructedin sucha mannerthatit cannotbedisassembledfor storage.storableswimmingpool446 EBCS-10 1995a pool constructedin sucha mannerthat it may bereadilydisassembledfor storageandreassembledto itsoriginalintegrity.ETHIOPIAN BUILDING CODE STANDARDSECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATIONformingshell a structureintendedfor mountingin a swimmingpool structuretosupportawet-nicheluminaireassembly.wet-nicheluminaire a luminaireintendedfor installationin a formingshellmountedinapoolstructurewheretheluminairewill becompletelysurroundedby pool water.dry-nicheLuminaire a luminaireintendedfor installationin thewall of apool in anichewhich is sealedagainsttheentryof poolwaterby a fixed lens.spaor hottub apoolortubdesignedfor theimmersionof personsin heatedwatercirculatedin closedsystemincorporatingafilter,heater,pump,andwithorwithoutamotordrivenblower,butnotintendedtobefilledanddrainedwith eachuse.hydromassagebathtup a permanentlyinstalledbathtubhaving an integral or remotewaterpumpor airblower,andhavinga fill anddrainwatersystem,andincludestherapeuticpools.leakagecurrentcollector a sectionof corrosionresistantmetaltubing.at leastfive timesaslong asitsdiameter,providedwith abrazedor weldedcopperlug.placedin a run of nonmetallicpipeto providea pathto earthforcurreritleakageoriginatingfromdevicein contactwithpoolwater.decorativepool a pool thatcould be usedas a waddingpool that is largerthan1.5min anydimensionsandthatis readilyaccessibleto thepublic.25.4 GENERAL25.4.1EquipmentInstallation(1) Equipmentshallnotbe installedin thewallsnor in thewaterof poolsexceptaspermittedby this Section.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 447ELECTRICAL INSTALLATION OF BUILDINGS25.4.2 OverheadWiring25.4.2.1 General(1) Thereshallnotbe~y overheadwiringabovethepool,divingstructures,observationstand,tower or platform,or abovethe areaextending3.0mhorizontallyfrom the pool edge(seeFigure 25.1)exceptaspermittedby 25.4.2.2and25.4.2.3.25.4.2.2 Communicationconductorsandcablesnot exceeding750.0V(1) Insulatedcommunicationconductors,communicationantennadistributionconductors,andIneutralsupportedcablesnot exceeding750.0Vshallbe permittedto be locatedover a pool,diving structure,observationstand,tower or platform,or abovethe area~xtending3.0mhorizontallyfromthepooledge,providedthereis aclearancemeasuredradiallyof atleast4.5m.25.4.2.3 Conductorsoper4tingat no morethan 50.0kV(1) Conductorsotherthanthosecoveredby 25.4.2.2andoperatingatnot morethan50.0~Yphase-to-phaseshallbepermittedtobelocatedaboveapool,divingstructure,observationstand,toweror plate,or abovetheareaextending3.0mhorizontallyfromthepooledgeprovidedthereis a clearancemeasuredradiallyof at least7.5m.25.4.3UndergroundWiring(1) The horizontalseparationbetweenthe insidewalls of pool andundergroundconductors,exceptfor bondingconductorsor conductorssupplyingelectricalequipmentassociatedwiththepool and protectedby an earthfault circuit breaker,shall be not lessthanthat showninTable25.1.448 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATIONTable25.1 Minimumconductorseparationfrompools,Minimum separation [m]Type of InstallationConductor buried directly inConductor in undergroundgroundracewaysCommunication conductors1.50.75Electrical conductors0- 750.0V0.750.75751V - 15000.0V3.001.5015001V - 25000.0V4.002.0025.4.4 Bondingto Earth25.4.4.1 General(1) Themetalpartsofthepoolandothernon-electricalequipmentassociatedwiththepoolsuchaspiping,pool reinforcingsteel,ladders,divingboardsupports,andfenceswithin 1.5mof thepool, shallbebondedtogetherandto'non-currentcarryingmetalpartsof electricalequipmentsuchasdecorativetype-poolluminariesandlightingequipmentnotlocatedin a formingshells,metalscreensof shieldsfor underwaterspeakers,conduit,junctionboxes,andthe like by acopperbondingconductor.Exemption: The metalpartsof a pool neednotbebondedto earthor to eachotherwheretheelectricalequipmentassociatedwith thepool is:a) not locatedwithin 3.0mof thepool,b) suitablyseparatedfrom thepool by a fence,wall, or otherbarrier,orc) approvedwithouta bondingconductor25.4.4.2 Reinforcingsteel(1) Pool reinforcingsteelshallbebondedwith aminimumof fourconnectionsequallyspacedaroundtheperimeter.ETHIOPIAN BUILDING CODE STANDARD EBC$-10 1995 449--------------------------------------------------------------~ELECTRICAL INSTALLATION OF BUILDINGS25.4.4.3 Bondingconductorsize(1) Bondingconductorsfor poolsshallbe:a) nosmallerthan16.0mm2for permanentlyinstalledpoolsandfor all in-groundpools;orb) asrequiredby Table7.1of Section7 for all otherpools.25.4.4.4 Bondingmedium(1) Metal sheathandracewaysshallnotbe relieduponasthebondingmediumandseparatecopperbondingconductorshallbeused.Exemptions:a) A metallicconductorbetweena formingshellandits associatedjunctionbox shallbepermittedtobeusedasthebondingmediumprovidedtheformingshellandjunctionboxareinstalledin thesamestructuralsection.b) The bondingconductorshall be of copperandnot smallerthanthatrequiredby Table 7.1.25.4.4.5 Junctionboxbondingconductor(1) The bondingconductorfromthejunctionbox referredto in Clause25.4.5shallberuntothe main distributionboard,and, if it is smallerthan 16.0mm2,it shall be installedandmechanicallyprotectedin thesamemannerasthecircuitconductor.25.4.5 JunctionandI)eckBoxes25.4.5.1 General(1) Junctionboxes:a) shallbepermittedto besubmergedin decorativepoolsprovidedtheboxesaremarkedfor suchusage;andb) conduitsshallbewater-tightandprovidedwith apackingsealthatwill sealaroundthecordandeffectivelypreventwaterfromenteringtheboxthroughtheconduitfrom theformingshell.450 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATION25.4.5.2 Deckboxes(I) Junction'installedon the supplysideof conduitsextendingto fonning shells,referredhereinafteras 'deckboxes',shallbespecificallyapprovedfor thepurposeandshall:a) be provided with a meansfor independentlytenninatingat least three bondingconductorsinsidethebox andone16.0mm2bondingconductoroutsidethebox;b) notcontaintheconductorsof anycircuitsotherthanthoseusedexclusivelyto slPplytheunderwaterequipment;andc) be providedwith electricalcontinuitybetweeneveryconnectedmetalconduitandthebondingtenninalsby meansof copper,brassor othercorrosion-resistantmetalthatisintegralwith thebox.25.4.5.3Deckboxinstallation(1) Deck boxesshallbe installed:a) abovethenonnalwaterlevelof thepool;b) sothatthetopof thebox is locatedator abovethefinishedlevelof thepool deck;c) in a manneror locationthattheboxwill notbeanobstacle;andd) in sucha mannerthatanywateronthedeckwill drainawayfromthebox.25.4.6 TransformersandTransformerEnclosure25.4.6.1 Location(1) Transfonnersshallnotbelocatedwithin3.0mof theinsidewall of thepoolunlesssuitablyseparatedfromthepool areaby a fence,wall or otherpennanentbarrierwhichwill makethetransfonnernotaccessibleto personsusingthepoolarea.25.4.6.2 Bonding(I) A metalshield,if providedbetweentheprimaryandsecondarywindingsof a transfonner,shallbebondedto earth.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 451ELECTRICAL INSTALLATION OF BUllDtNGS25.4.6.3 Audio transformer(1) Audio isolationtransformersshall:a) beconnectedbetweentheaudiooutputterminalsof eachamplifierandanyloudspeakerwhich is locatedwithin3.0mof thepool wall; andb) be locatedin or adjacentto theamplifierwith whichtheyareused;andc) haveanaudiooutputvoltageof notmorethan75.0Vr.m.s.25.4.7 SocketOutlets25.4.7.1 Location(1) Socketoutletsshallnotbe locatedwithin 1.5mof theinsidewalls of thepools.25.4.7.2 Protection(1) SockclDutletslocatedbetween1.5mand3.0mof theinsidewall of apoolshallbeprote~tedby anearth-faultcircuitbreaker.25.4.8 LuminariesandLightingEquipment25.4.8.1.2 Submersiondepth(1) Wet-nicheluminariesshall,exceptfor decorativepools,bemountedin formingshellswhichshallhaveprovisionfor suitableconnectionto thewiring methodused.ETHIOPIAN BUilDING CODE STANDARDWet-nicheor submersibleluminaireGeneral452 EBCS-10 1995Note: In maintainingthedimensionsreferredto in Clause25.4.7,thedistancetobemeasuredis theshortestpaththatthepowersupplycordof anapplianceconnectedtothesocketoutletwould follow withoutpiercingabuilding floor, wall, or ceiling.(1) Wet-nicheluminariesshall,unlessspecificallyapprovedandmarkedfor submersionat agreaterdepth,not be submersedin the pool waterat a depthof morethan600.0mm,suchdistancebeingmeasuredfromthecentreof thelensefaceof theluminaireto thenormalwaterlevel.25.4.8.125.4.8.1.1SECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATION25.4.8.1.3 Voltage(1) Wet-nicheluminaireshalloperatewith neitherthesupplyvoltageto the luminairenor theassociatedballastor transformer,if applicable,nor thesecondaryopen-circuitvoltageof theballastor transformerexceeding230.0Vduringeitherstartingor operatingvoltage.25.4.8.2 Dry-nicheluminaire25.4.8.2.1 Voltage(1) Wheredry-nicheluminariesareinstalledsoastobeaccessiblefromawalkwayor aservicetunneloutsidethewalls of thepool or from a closeddrainedrecessin thewall of thepool,neitherthe supplyvoltageto thefixturenor its associateballastor transformershallexceed380.0Vduringeitherstartingor operatingconditions.25.4.8.2.2 Accessib~lity(1) Dry-nicheluminariesshallbeaccessiblefor maintenance:a) from a servicetunnelor walkwayoutsidethewalk of thepool,orb) throughahandholein thedeckof thepooltoa closed,drainedrecessin thewall of thepool.25.4.8.3 Metalparts(1) Metal partsof lumnairesin contactwiththepool watershallbeof brassor othersuitablecorrosion-resistantmaterial25.4.8.4 Luminairesupport(1) Standsor supportsfor luminariesshallnotbe installedwithin3.0mof theinsidewalls ofa swimmingpool unlesssuchluminariesareprotectedby earth-faultcircuitbreaker.25.4.8.5 Luminaireprotection(1) Luminariesinstalledbelowor within 3.0mof thepool surfaceor walls, andnot suitablyseparatedfrom the pool areaby fence,wall or otherpermanentbarriershall be electricallyprotectedby anearth-faultcircuitbreaker.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 453ELECTRICAL INSTALLATION OF BUILDINGS25.4.8.6 Formingshelltypes(1) Formingshellsfor lampssuppliedfromanearthedcircuitor a circuitoperatingatvoltageexceeding30.0V shallbemadefrom metalandhaveprovisionfor a threadedconnectionto arigid metalconduit.25.4.9 Earth-FaultCircuitBreakers25.4.9.1 General(1) Exceptaspermittedin 25.4.9.2,earth-faultcircuitbreakersrequiredpertheprovisionsofClause25.4.9shallbeof ClassA typet.25.4.9.2 Otherclasses(1) Whereearth-faultcircuitbreakersof theClassA typearenotavailabledueto rating,theequipmentshallbe protectedby an earth-faultcircuitbreakerwhichwill clearanearthfaultwithin thetimespecifiedfor ClassA typebreaker.25.4.9.3 Installation(1) Earth-faultcircuitbreakersshallbe:a) permanentlyconnected,b) permittedto beappliedto a feeder,a branchcircuitor an individualdevice,c) installedin a locationwhichwill facilitatetestingrequiredin 25.4.9.4,but not closerwithin 3.0mof thepool water.25.4.9.4 Warningsign(1) A warningsignshallbelocatedbesidetheswitchescontrollingcircuits,electricallyprotectedby earth-faultcircuitbreakers,advisingthatthecircuitsareprotectedandthattheequipmentshallbetestedregularly.t SeeClauseA.2, AnnexA.454 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARD25.5.1 General25.5 PERMANENTLY INSTALLED SWIMMING POOLS25.6 STORABLE SWIMMING POOLSEBCS-10 1995 455ETHIOPIAN BUILDING CODE STANDARD25.6.1 Electrical Equipment(1) Conduitsin the walls and deckof a swimmingpool shall be installedso that suitabledrainageis provided.25.5.4 Drainage(1) Conductorson the load side of eachearth-faultcircuit breakersshall be kept entirelyindependentof all otherwiring which is not so protectedand shall not entera luminaireraceway,box, or cabinetoccupiedby otherwiring exceptfor panelboardswhich housethebreakers.Exemption: WhereClauses25.5.1and25.5.2donotapply,anysuitablewiringmethodspecifiedin Section8of thisStandardshall be permitted.25.5.3 Circuft Segregation25.5.2 Conduit Type(1) The wiring betweenthe wet-nicheluminariesand the junction boxesreferredto inClause25.4.5shallbe of flexiblecordsuitablefor usein wet locationsandsuppliedasa partof the luminaire.SECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATION(1) Rigid conduitof copperor othercorrosion-resistantmetalor rigid PVC conduitshallbeprovidedbetweenthe forming shell of luminaireinstalledbelow the pool surfaceand thejunctionbox referredto in Clause25.4.5./'(1) No electricalequipmentshall be locatedin the pool wateror on the pool wall unlessspecificallyapprovedfor thepurpose.ELECTRICAL INSTALLATION OF BUilDINGS25.6.2 Pumps25.6.2.1 General(1) Swimmingpoolpumpslocatedwithin3.0mofthe poolwallsshallbespecificallyapprovedfor thepurpose.25.6.2.2 Supply(1) Swimmingpoolpumpsshallbesuppliedfromapern'lanentlyinstalledreceptaclelocatednotlessthan 1.5mnor morethan7.5mfromthepool walls.25.6.2.3 Protection(1) Swimmingpoolpumpsshallbeprotectedby anearthfault-circuitbreakerif locatedwithin3.0mof the insidewalls of thepool andnotsuitablyseparatedfromthepool areaby a fence,wall, or otherpermanentbarrier.25.7 HYDROMASSAGE BATHTUB25.7.1Protection(1) Electricalequipmentforminganintegralpartof ahydromassagebathtubshallbeprotectedby an earth-faultcircuitbreakerof theClassA type.25.7.2 Control25.7.2.1 Timer switch(1) A hydromassagebathtubshallbecontrolledby anautomaticshut-offtimerwith an 'on'timeof notmorethan30.0min.25.7.2.2 Controls location(1) Electricalcontrolsassociatedwith ahydromassagebathtubshallbelocatedbehindabarrieror shallbe locatednot lessthan1.Omhorizontallyfroma wall of thebathtubunlesstheyforman integralpartof anapprovedfactory-builthydromassagebathtub.456 EBCS-10 1995 ETHIOPIAN BUilDING CODE STANDARDSECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATION25.7.2.3 Earthfault circuitbreakerlocation(1) Subjectto 25.7.2.2andnotwithstandingtheprovisionsof 25.4.9.3(1c),earth-faultcircuitbreakersshallbepermittedto becloserthan3.0mtothepool butnotlessthan1.5mfromthepool wall.25.7.3OtherElectricEquipment(1) Luminaries,switches,socketoutlets,andotherelectricalequipmentnotdirectlyassociatedwith ahydromassagebathtubshallbeinstalledin accordancewithrelevantClausesof thisCodecoveringthe installationof equipmentin bathrooms.25.8 SPAS AND HOT TUBS25.8.1 BondingtoEarth25.8.1.1 General(1) Metal partsof spasandhot tubsshallbebondedtogetherandto earthin accordancewiththeprovisionsof Clause25.4.4.Exemption: Metal rings or bandsusedto securestavesor woodenhot tubsneednot be bonded.25.8.1.2 Bondingconductorsize(1) A copperbondingconductorwhosesize is not lessthanthatof the circuit conductorssupplyingtheequipmentshallbeconnectedbetweenthecontrolpanelof a spaor hottubandtheconsumer'sserviceor distributionpanel.25.8.2 ControlsandOtherElectricalEquipment'25.8.2.1 Controls(1) Controlsfor spaor hottubshallbe locatedbehinda barrieror shallbe locatednotwithin1.5mhorizontallyfrom spaor hottubunlesstheyformanintegralpartof anapprovedfactorybuilt spaor hot tub.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 457ELECTRICAL INSTALLATION OF BUILDINGS25.8.2.2 Socketoutlet(1) Socketoutletsshallbe installedin accordancewith Clause25.4.7.25.8.2.3 Luminaries(1) Luminairesshallbe installedin accordancewith Clause25.4.8.25.8.3 LeakageCurrent25.8.3.1 Installation(1) Leakagecurrentcollectorsshallbe installedin all waterinletsandin all wateroutletsof afield-assembledspaor hottubso thatall waterflows throughleakagecurrentcollectors.Exemption: Leakagewatercurrentcollectionshallnot berequiredin a systemin which theonly componentis apumpmarkedas 'insulatedwet-endpump'.25.8.3.2 Insulationandbonding(1) Leakagecurrentcollecto~hall beelectricallyinsulatedfromthespaor hottub andshallbebondedto thecontrolpanelor themainserviceearthwith a copperbondingconductor.25.8.3.3 Bondingconductorsize(1) Thebondingconductorfor leakagecurrentcollectorsshallbenotsmallerthanthatrequiredby Table7.1,Section7, wherethebondingconductorsaremechanicallyprotectedin thesamemannerasthecircuitconductoror a minimum16.0mm2copperconductor.25.8.4 Field-AssembledUnits25.8.4.1 General(1) Spas and hot tubs, field-assembledwithin divided components,shall be installed IIIaccordancewith theprovisionsof Clauses25.8.1through 25.8.3,25.8.4.2and25.8.4.3.458 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 25: SWiMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATION25.8.4.2 Component(1) Individualcomponents,suchaspumps,heaters,andblowers,shallbespecificallyapprovedfor usewith spasor hot tub.25.8.4.3 Air blowerinstallation(1) Air blowershallbe installedabovethetubrim, or otheracceptablemeansshallbeusedtopreventwaterfrom comingintocontactwith live partsof theblower.Note: No conductorswould be permittedunderany circumstancesin theareaunderline I. In the areaaboveLine I insulatedcommunicationconductorsandneutralsupportedcablesoperatingat750.0Vor lessmightbepermitted.Any otherconductorsoperatingatnotmorethan50.0kV mightbepermittedabovetheareaoutlinedby line 2.All dimensionsare in metres.Figure 25.1 Minimum clearancesof conductorsoverswimmingpoolETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 459ANNEX A (INFORMATIVE)A.I AUDIO ISOLATION TRANSFORMERSAudio isolationtransformesshould:a) haveeitherthe primaryand secondarywindingswound on separatebobbins'Onthecore legsor a groundedmetalshieldbetweenthe primaryand secondarywindings;andb) be capableof withstandinga 60.0Hztestvoltageof ,2500.0Vappliedbetweentheprimaryand secondarywindingsfor a periodof 1.0minwithout a breakdown.Microphones used in the vicinityof pools and baptismalfonts musthaveaudio isolationtransformersandcableswith ungroundedconductorsinstalledbetweenthemandanymixer,preamplifier,amplifieror similarequipment.A.2 AN EARTH FAULT CIRCUIT INTERRUPTERAn earth-fault circuit interrupter is a devicewhose function is to interrupt, WHnmapredeterminedtime, the electriccircuit to a load when the currentto earthexceedssomepredeterminedvalue that is lessthan that requiredto operatethe overcurrentprotectivedeviceof that circuit.More specifically,a ClassA earth-faultcircuit interrupteris one which will interrupt thecircuit to the load when the earth-faultcurrentis 6.0mA or more,but not when the earthf~,ultcurrent is 4.0mA or less in a time:a) not greaterthanthatgivenby:T20I (A.I)46.0 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 25: SWIMMING POOLS, FOUNTAINS AND SIMILAR INSTALLATIONwhere T is thetimein seconds,I is theearthfaultcurrentin La.msmilliamperesfor faultcurrent~between4.0mAand260.0mA.Note: whentheambientairtemperatureislessthan-SoCormorethan40C,theminimumtrippingcurrentmaybe3.5mAinsteadof 4.0mA.b) notgreaterthan25.0msforearth-faultcurrentsover260.0mA.In addition,a ClassA earth-faultcircuitinterruptershouldbecapableof interruptingthecircuitto the loadin keepingwith theaboverequirementsshouldthe identifiedcircuitconductor(neutral)becomeinadvertentlyearthedbetweentheinterrupterandtheload.Theprimefunctionof aClassA EFCI, therefore,istoprovideprotectionagainsthazardouselectricshocksfromleakagecurrentflowingto earthfromdefectivecircuitsor equipment.It doesnotprovidedprotectionagainstshockshouldapersonmakecontactwithtwoof thecircuitconductorson theloadsideof theEFCI.An EFCI mustbeappliedto a circuitin accordancewiththetypeandratingof thecircuitforwhichit is designed.ETHIOPIAN BUilDING CODE STANDARD EBCS-10 1995 461rSECTION 26GRAPHICAL SYMBOLS26.1 SCOPE(1) ThisSectionof theCodesetsprovisionsforgraphicalsymbolsto beusedin electricalinstallationsanddegreeof protectionprovidedbyenclosuresfor electricalequipment.26.2 NORMATIVE REFERENCES(1) The followingreferencescontainprovisionswhich,throughreferencein this text,constituteprovisionsof theEthiopianBuildingCodeStandardonElectricalInstallationofBuildings:a) mc529:1989b) DIN 407117:198326.3 DEFINITIONSDegreeof protectionprovidedby enclosures(IFCode).Graphical Symbols for Diagrams ElectricalInstallation.(1) For thepurposeof thisSectionof theCode,thefollowingdefinitionsshallapply,inadditionto thetermsdefinedin Section1:degreeofprotectionIP (InternationalProtection)Code462 EBCS-10 1995theextentof protectionprovidedby an enclosureagainstaccessto hazardousparts,againstingressofsolidforeignobjectsand/oragainstingressof waterand verified by standardizedtest methodsasspecifiedinmc529:1989.a codingsystemtoindicatethedegreeof protectionprovidedbyanenclosureagainstaccesstohazardousparts,ingressof solid foreignobjects,ingressofwater and to give additional information inconnectionwithsuchprotectionasspecifiedin mc529:1989.ETHIOPIAN BUILDING CODE STANDARDSECTION 26: GRAPHICAL SYMBOLS26.4 SYMBOLS(1) Symbolsforelectricalinstallationsanddegreeof protectionprovidedbyenclosuresforelectricalequipment(lightingfittings)shall be as indicatedin Tables26.1and26.2,respectively.Table 26.1Graphical symbolsfor electricalinstallationsSYMBOL DESCRIPTIONline SystemsConductor,general--JJ'--FlexibleconductorIdentification of Installation Method--Undergroundline--Overhead line.Surfaceline~In/Under surfacelineIdentification of IntendedApplication-----ProtectiveConductor (PEl-'-.-Signal line-'-'-Telephone line- ...- ...-Radio lineSupply lines/ Wiring going upward/ Wiring going down/ Wiring passingthroughvertically Junction of conductorsfor flush installationNote: Darkenedsymbolsindicateflush[recessed]installations.ETHIOPIAN BUILDING CODE STANDARD .EBC$-10 1995 463ELECTRICAL INSTALLATION OF BUILDINGSTable 26.1Graphical symbolsfor electricalfnstallations(conte'd)SYMBOL--0--DESCRIPTIONSupply Lines (conte'd)Junction of conductors for surface installationsEarthingSurface mounted (central) main distributionboardFlush mounted (central) main distribution boardSurface mounted sub-distribution boardFlush mounted sub-distribution boardSwitchgearFuse, generalThree-pole fuse, generalLow voltage HRC fuseFuse disconnectorSwitchAutomatic breaker for line protectionBreaker with thermal over-current trip, e.gMotor circuit break-etStar-deltaMotor Starteroirect-on-Iine starterSwitches used for installation purposesOn-off switch, single-poleOn-off switch, double-poleOn-off switch, triple-poleTwo-circuit switch, single interruption.Two-way switch, single-polePush-buttonNote: Darkenedsymbolsindicateflush[recessed]installations.464 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 26: GRAPHICAL_SYMBOLSTable26.1Graphicalsymbolsforelectricalinstallations(conte'd)SYMBOL DESCRIPTIONSwitches usedfor installationpurposes(conte'd),Push-buttonwith indicatorlamp~Dimmerswitch(0Light-sensitiveswitch@Floatswitch- 76) Time switchIsl Currentpulseswitch/OJTime relaySocketOutletsA.Single-phas'esocketoutletA~single-phasesocketoutlet+ PE--- rh Twin socketoutletc----- '~ Socketoutletwith switchf- ~ Three-phasesocketoutlet +PEn,TelephonesocketoutletRnAntennasocketoutlet!/,.0EmptyboxI !LuminairesXLuminairegeneralsymboltxWall mountedluminaire'XLuminairewith switchXEmergencyluminaireexFlood light(Projector)-I)( I Florescentluminairesingle lamp'~-Note:Darkenedsymbolsindicateflush[recessed]installationsETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 465ELECTRICAL INSTALLATION OF BUILDINGSTable 26.1Graphical symbolsfor electricalinstallations(conte'd)SYMBOL DESCRIPTIONLuminaires(conte'd)Ix I Florescentluminairedouble lampIIIxIIRow of florescentluminaireExteriorluminaire(posttop)Indicating Instruments and TransformersSIndicatinginstrumentsIKwhm0Metre (kilowatthour-metre)-0. Currenttransformer-CID- VoltagetransformerPower Supply Units[Z] ConvertorGeneral Symbol~ Rectifier-Ir-- Battery(Cell)~ InverterElectrical Appliances (Power)[J Electricalappliance,General symbol~ Kitchenappliance~ Electricrange,generalsymbol~ Microwave cooker~ Bakingoven~ Hotplate0+- Water heaterfl Washing machineNote: Darkenedsymbolsindicateflush[recessed]installations.466 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 26: GRAPHICAL SYMBOvOTable 26.1Graphical symbolsfor electricalinstallations(conte'd)SYMBOL DESCRIPTIONElectricalAppliances(conte'd)~IClothesdryer~Dish washerfanE!JAir conditioning1** IFreezer[*** 1Deep freezer@IMotorGeneratorCommunication appliancesg Intercom[Q] Telephone exchange, general symbolLf-o-Jlj AutomaticTelephoneexchangeSignalling Devices~ BellCJ:=:=7Horn=:j)SirenUCall indicatorpanel (Number indicatescallstations,for example9 stations)0ElectricClockMasterClockJ[I~INon-automaticfirealarmdevice(manualfirecall point)II=:JIFire alarmcontrol & indicatingpanelI~lSmokedetectorNote: Darkened symbolsindicate flush [recessed]installations.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 467ELECTRICAL INSTALLATION OF BUILDINGSTable 26.1Graphical symbolsfor electricalinstallations(conte'd)SYMBOL DESCRIPTION,Signalling Devices(conte'd) I=::::l Optical detector-[[JJ Heatdetector(fixedtemperature)em..-Heatdetector(rateof rise)1(21ZSJ IFlamedetectorRadio, Television and accessoriesrAntenna[EJAmplifieroJLoud speaker----] RadiosetIe:=:::)ITV set,.Note: Darkenedsymbolsindicateflush[recessed]installations.468 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDSECTION 26: GRAPHICAL SYMBOLSTable26.2 Graphicalsymbolsfor thedegreeof protectionof electricalequipment(symbolson lightfittings)SYMBOLType of11s1 Digit - Protection against2nd Digit - ProtectionProtectionforeign substancesagainstwaterIP 20I Covered no protectionIP 30foreignsubstances2.5mm~no protectionIP 40foreignsubstances1.0mm~I no protection+IP 50dust proof no protection-----,+ IP 60dust proof no protectionIP 22covered inclined drippingwater[!lIP 23covered rain[!]IP 43foreignsubstance1.0mm~I rainLtIP 44foreignsubstance1.0mm~I splashwater$ANNEX A (INFORMATIVE)SYMBOLS ON LIGHT FITTINGS COMPLYINGWITH IEC 598.Test marksSYMBOL DESCRIPTION@The VDE-test mark is the symbol of the association'Verein DeutscherElektrotechiker'(~AssociationofGerman Electrical Engineers.)The approval is based on internationallyspecified rules.It certifies thesuccessfullypassedtestsaccordingto the safetyregulationsand the VDE-and the IEC-specifications.- lighting fittings for dischargelamps with this sign are suitablefor directmountingon normalor easilyWinflammablematerials,complywith DlN 4102, as farastheir inflammationtemperatureis at le,!?tat 200C,and if they remainstableand are not subjectto deformationuptothis temperature.V'VLighting fittingssuitablefor mounting in fire-hazardouslocationsand premises(VDE 0100)IP 50 (dustproof) is at leastrequired.WLightingfittingsfor dischargelampsfor directmountingon fixturesand furnitures,which conform in theirbehaviour for inflammationto hardlyor normally inflammablematerials,althoughif thesematerialsbeingvarnished,coatedor veneered.WWLightingfittingssuitablefor mountingon materialswith unknown inflammabiIity.Theprocedureof mountingis specified.(@Radio interference suppressionaccording to VDE 0875. All lightingfittingsconform to the interferencesuppressiondegreeG. By usingadditionalinterferencesuppressiondevicedegreeN will be reached.f!JJImpact proof lighting fittingsare suitablefor gymnasticandsportspremises. The testsare madeaccordingto DIN 18032 and VDE 0711.470 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDANNEX B (INFORMATIVE)PROTECTION CLASSESThelightfittingsareclassifiedin threecategoriesagainstelectricalshocksdependingonthetypeofprotection.SYMBOL DESCRIPTIONClass IProtectivewire required--The lighting fitting has protective0 Class II insulation,aprotectivewireis,therefore,not required.For Iightingfittingswith incandescent~lampsfor connection to low voltageClass IIIwithprotectiveinsulation(Max.42.0V). A protective wire is notallowed.ETHIOPIAN BUILDING COi)&STANDARD EBCS-10 1995 471APPENDICESAPPENDIX 1INSPECTION AND TESTING1 INITIAL VERIFICATION1.1 General(1) Everyinstallationshall,duringerectionand/oroncompletionbutbeforebeingputintoservice,be inspectedand testedto verify,.so far as is reasonablypracticable,that therequirementsof thisElectricalInstallationCodehavebeenmet.(2) The methodof testshallbe.suchthatno dangerto persons,livestockor propertyordamageto equipmentcanoccurevenif thecircuittestedisdefective.1.2 Inspection(1) Detailedinspectionshallprecedetestingandshallnormallybe carredoutwith thatportionof theinstallationunderinspectionbeingdisconnectedfromthesupply.(2) ThedetailedinspectionshallbemadetoverifythattheinstalledelectricalequipmentIS:a) in compliancewiththisElectricalinstallationCode;b) correctlyselectedanderectedin accordancewiththisElectricalInstallationCode;andc) notvisiblydamagedor defectivesoasto impairsafety.(3) Thedetailedinspectionshallincludeatleastthecheckingof thefollowingitems,whererelevantto theinstallation,and,wherenecessary,duringerection:ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 A-1,ELECTRICAL INSTALLATION OF BUILDINGSa) connectionof conductors;b) identificationof conductors;c) routingof cablesin safezonesor mechanicalprotection;d) selectionofconductorsforcurrentcarryingcapacityandvoltagedropinaccordancewiththedesign;e) connectionof singlepoledevicesfor protectionor switchingin phaseconductorsonly;t) correctconnectionsocket-outletsandlampholders;g) presenceof firebarriersandprotectionagainstthermaleffects;h) methodsof protectionagainstdirectcontact(includingmeasurementof distances,whereappropriate);i.e.,i) protectionbyinsulationof liveparts,ii) protectionbybarrieror enclosure,ill) protectionbyobstacles,iv) protectionbyplacingoutof reach;i) methodsof protectionagainstindirectcontact;i.e,i) presenceof protectiveconduqtors,ii) presenceof earthingconductors,iii) presenceof mainequipotentialbondingconductors,iv) earthingarrangementsforcombinedprotectiveandfunctionalpurposes,v) useof ClassII equipmentorequivalentinsulation,vi) non-conductinglocation (includingmeasurementof distances,whereappropriate),vii) earth-freelocalequipotentialbonding,viii) electricalseparation;j) preventionof mutualdetrimentalinfluence;k) presenceof appropriatedevicesfor isolationandswitching;1) presenceof under-voltageprotectivedevices;m) choiceandsettingof protectiveandmonitoringdevices(for protectionagainstindirectcontactand/orprotectionagainstovercurrent);n) labellingof circuits,fuses,switchesandterminals;0) selectionof equipmentandprotectivemeasuresappropriatetoexternalinfluences;p) adequacyof accesstoswitchgearandequipment;q) presenceof dangernoticesandotherwarningnotices;r) presenceof diagrams,instructionsandsimilarinformation;s) erectionmethods.A-2 EBCS-101995 ETHIOPIAN BUILDING CODE STANDARDAPPENDIX 1: INSPECTION AND T1STING1.3 Testing1.3.1 Teststobecarriedout(1) The followingtests,whererelevant,shallbecarriedoutin thatsequence.a) continuityof protectiveconductorsi) Everyprotectiveconductorshallbetestedtoverifythatit iselectricallysoundandcorrectlyconnected.b) continuityof ringfinalcircuitconductorsi) A testshallbemadetoverifythecontinuityof eachconductor,includingtheprotectiveconductor,of everyringfinalcircuit.c) Insulationresistancei) The insulationresistancebetweenliveconductorsshallbemeasuredbeforetheinstallationisconnectedto thesupply.ii) Particularattentionshallbe givento the presenceof electronicdevicesconnectedin the installationand,wherenecessary,suchdevicesshallbeisolatedsothattheyarenotdamagedbythetestvoltageandthereaftertestedin accordancewith (vi)below.iii) The insulationresistanceshallalsobemeasuredbetweeneachliveconductorandearth,thePEN conductorin TN-C systemsbeingconsideredaspartoftheearth. Whereappropriateduringthismeasurement,phaseandneutralconductorsmaybeconnectedtogether.iv) The insulationresistancemeasuredwith the d.c.testvoltagesindicatedinTable1 shallbe consideredsatisfactoryif the mainswitchboard,andeachdistributioncircuittestedseparatelywithall its finalcircuitsconnectedbutwithcurrent-usingequipmentdisconnected,hasan insulationresistancenotlessthanthevaluegivenin Table1.v) Thetestingequipmentshallbecapableof supplyingthetestvoltageindicatedin TableA.1whenloadedwith1.0mA.vi) Whereequipmentsuchaselectronicdevicesaredisconnectedfor the testsprescribedin a(i) through c (v) aboveandtheequipmenthasexposedconductivepartsto be connectedto protectiveconductors,the insulation,ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 A-3ELECTRICAL INSTALLATiON OF BUILDINGSresistancebetweenthe exposedconductiveparts and live parts of thedisconnectedequipmentshallbe measuredseparatelyandshallbe not lessthanO.5megaOhm.Table1: Minimumvaluesof insulation-resistanceCircuit nominalvoltage[V] Testvoltaged.c.Minimuminsulationresistance[V](megaOhms)Extra-lowvoltagecircuitswhenthecircuitis suppliedfroma safety~O0.25isolatingtransforinerUp to andincluding500.0Vwiththe5000.5exceptionof theabovecasesAbove500.0Vup to 1000.OV10001.0BetweenSELV cirCuitsand5005.0associatedLV circuitsNote: i) In theeventofanytestindicatingfailuretocomplywiththerequirmentsof clause(lc) above,thattestandthoseprecedingit (theresultsofwhichmayhavebeeninfluencedbytheindicatedfault)3hallberepeatedafterthefaulthasbeenrectified.ii) Referencemethodsof testaredescribedin GuidanceNotesontheWiringRegulationspublishedby the Institutionof ElectricalEngineers(IEE); but the useof othermethodsgivingno lesseffectiveresultsis notprecluded.d) Siteappliedinsulation(i) Whereinsulationappliedonsiteis intendedto provideprotectionagainstdirect contact,it shall be verifiedthat the insulationis capableofwithstanding,withoutbreakdownor flashover,an appliedvoltagetestequivalentto thatspecifiedin therelevantacceptableStandardfor similartype-testedequipment.(ii) Whereprotectionagainstindirectcontactis providedby supplementaryinsulationappliedtoequipmentduringerection,it shallbeverifiedbytestthat:- the insulatingenclosureaffordsa degreeof protectionnot lessthanIP2X, andA-4 EBCS-10 1995 ETHIOPIAN BUILDING CODE STANDARDlAPPENDIX 1: INSPECTION AND TESTING- . theinsulatingenclosureiscapableof withstanding,withoutbreakdownor flashover,anappliedvoltagetestequivalentto thatspecifiedin therelevantacceptableStandardfor similartypetestedequipment.e) Protectionbyseparationof circuits(i) Whereprotectionagainstelectricshockis providedbySELV, it shallbeverifiedbyinspectionandtest.(ii) Whereprotectionagainstelectricshockisprovidedbyelectricalseparation,it shallbeverifiedbyinspectionandtest.t) protectionagainstdirectcontact,byabarrierorenclosureprovidedduringerection(i) Whereprotectionagainstdirectcontactis intendedto be affordedby abarrieror enclosureprovidedduringerection,it shallbeverifiedby testthateachenclosureor barrieraffordsa degreeof protectionnotlessthanlP2X or lP4X asappropriate.g) Insulationof non-conductingfloorsandwalls(i) Whereprotectionagainstindirectcontactis to be providedby a non-conductinglocation,theresistanceof thefloorsandwallsof thelocationto themainprotectiveconductorof theinstallationshallbe measuredatnotlessthanthreepointson eachrelevantsurface,oneof whichshallbenotlessthan1.0mandnotmorethan12mfromany~xtraneousconductivepartin thelocation.Theothertwomeasurementsshallbemadeatgreaterdistances.(ii) Any insulationor insulatingarrangementof extraneousconductiveparts:- whentestedat500.0Vd.c.shallnotbelessthanO.5megaohm;- shallbeabletowithstanda testvoltageof atleast2.0kVr.m.s,a.c.and- shallnotpassa leakage'currentexceeding1.0mAin normalconditionsofuse.(h) Polarity(i) A testof polarityshallbemadeandit shallbeverifiedthat:- everyfuseandsingle-polecontrolandprotectivedeviceisconnectedin thephaseconductoronly;ETHIOPIAN BUILDING CODE STANDARD EBC~-l0 1995 A-5ELECTRICAL INSTALLATION OF BUILDINGS- centre-contactbayanetandEdisanscrewlamphaldersin circuitshavingan earthedneutralconductarhavethe auterar. screwedcontactsconnectedto.theneutralconductor;and- wiringhasbeencorrectlyconnectedto.sacket-autletsandsimilaraccessanes.(i) Earthfaultlaapimpedancei) Whereprotectivemeasuresthatrequirea knawledgeaf theearth-faultlaap,impedancesare,thereleventimpedancesshallbemeasured.G) Earthelectroderesistancei) Wherepratectivemeasuresareused,whichrequirea knawledgeaf theearthelectroderesistance,thisshallbemeasured.(k) Operatianaf residual-currentaperateddevices(i) Wherepratectianagainstindirectcontactis to.be providedby a resi~ualcurrentdevice,its effectivenessshallbe verifiedby a testsimulatinganappropriatefaultconditianandindependentaf anytestfacilityincorparatedin thedevice.2 ALTERATIONS AND ADDITIONS TO AN INSTALLATION(1) It shallbeverifiedthateveryalteratianor additiancomplieswiththerequirementsafthisCo.deandthatit daesnatimpairthesafetyaf anexistinginstallatian.3 PERIODIC INSPECTION AND TESTING(1) Inspectiancomprisingcarefulscrutinyaf aninstallatianshallbe carnedautwithautdismantlingorwithpartialdismantling,asrequired,supplementedbytestingto.providefar:a) thesafetyaf persansandlivestackagainsttheeffectsaf electricshackandburnsevenwhenthecircuitis defective,b) pratectianagainstdamageto.prapertybyfireandheatarisingfromaninstallatiandefect,A-6 EBCS-101995 ETHIOPIAN BUILDING CODE STANDARD'APPENDIX 1: INSPECTION AND rESTINGc) theidentificationthattheinstallationisnotdamagedordeterioratedsoasto impairsafety;d) theidentificationof installationdefectsornon-compliancewiththerequirementsofthisCodewhichmaygiveriseto danger.(2) The frequencyof periodicinspectionandtestingof aninstallationshallbedeterminedby thetypeof installation,its useandoperation,thefrequencyof maintenanceandtheexternalinfluencestowhichit issubjected.4 CERTIFICATION AND REPORTING4.1 General(1) FollowingtheinitialverificationrequiredbyClause1or Clause2 of thisAppendix,aCompletion& InspectionCertificatein theformsetoutin Appendix2 of thisCodeshallbegivento thepersonorderingthework.(2) Followingtheperiodicinspectionandtestingdescribedin Clause3 of thisAppendix,reporton the findings and the extentsof the periodicinspectionand.testingof aninstallation,or anypart thereof,shallbe recordedon a reportandgivenby thepersoncarryingout theinspection,or bya personauthorizedto acton hisbehalf,to thepersonorderingthework.(3) Dangerousconditionsarisingfromnon-compliancewiththisCode,togetherwithanylimitationsof theinspectionandtestingin accordancewithClause3(1)of thisAppendix,shallberecorded.4.2 InitialVerification(1) TheInspectionshallcomplywiththerequirementof Clause1of thisAppendixandanydefectsor omissionsrevealedbytheinspectionshallbemadegoodbeforea Completion& InspectionCertificateis issued.(2) The Completion& InspectionCertificateshallbe signedby a competentpersonorpersonsstatingthattheinstallationhasbeendesigned,constructedandinspectedandtestedin accordancewiththeprovisionsof thisCode.ETHIOPIAN BUILDING CODE STANDARD EBCS-101995 A-7ELECTRICAL INSTALLATION OF BUILDINGS4.3 AlterationsandAdditions(1) The requirementsof Clause4.2 fdr the issuanceof a Completion& InspectionCertificateshall applyto all the work of the alterationsor additions;anydefectsoromissionsrevealedin thatworkshallbemadegoodbeforea CompletionReportis issued.(2) The Contractoror otherpersonresponsiblefor thenewwork,or a personauthorisedto acton hisbehalf,shallreportin writingto thepersonorderingthework anydefectsfoundin relatedpartsof theexistinginstallation.A-8 EBCS-10 1995 ETHIOP!At'-J BUILDING CODE STANDARDAPPENDIX 2: FORMS OF COMPLETION AND INSPECTION CERTIFICATEAPPENDIX 2FORMS OF COMPLETION AND INSPECTIONCERTIFICATE1. Installation(1) The formsof completion,inspectionandtestingshallbemadeoutandsignedbycompetentpersonsin respectof thedesign,construction,inspectionandtestingof work.(2) Completedformsshallindicatearesponsibilityfor design,construction,inspectionandtesting,whetherin relationto newworkor furtherworkon anexistinginstallation.ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 A-9DESIGNFORMS OF COMPLETION & INSPECTION CERTIFICATEDETAILS OF THE INSTALLATIONClient:Address:'--I/We, beingtheperson(s)responsible(as indicatedby my/oursignaturesbelow)for theDesignof theelectricalinstallation,particularsofwhicharedescribedonPage...of thisForm,CERTIFY thatthesaidworkforwhichI/wehavebeenresponsibleis to thebestof my/ourknowledgeandbeliefin accordancewith the Regulationsfor Electrical, Installationspublishedby exceptfor thedepartures,if any,statedin thisCertificate.The extentof liabilityof thesignatoryis limitedto theworkdescribedaboveasthesubjectthisCertificate.For theDESIGN of theinstallation:Name(in blockletters):For andon behalfof:Address:(2) Signature:CONSTRUCTION(3)DatePosition: Reg.No.I/We, beingtheperson(s)responsible(asindicatedbymy/oursignaturebelow)for the'Constructionof theelectricalinstallation,particularsof whicharedescribedonPage....of thisFormCERTIFY thatthesaidwt>rkforwhichI/wehavebeenresponsibleis to thebestof my/ourknowledgeand felief in accordancewith the Regulationfor ElectricalInstallationspublishedby ..........................................................................................................exceptforthedepartures,if any,statedin thisCertificate.The extentof liabilityof thesignatoryis limitedto theworkdescribedaboveasthesubjectof this'.Certificate.For theCONSTRUCTION of theinstallation:Name(in blockletters):For andon behalfof:Address:(2) Signature:INSPECTION AND TESTPosition:(3)Date:Reg.No.I/We, beingtheperson(s)responsible(as indicatedbymy/oursignaturesbelow)for theInspectionandTestof theelectricalinstallation,particularsofwhicharedescribedonPage...of thisForm,CERTIFY thatthesaidworkforwhichl/we havebeenresponsibleis to thebestof my/ourknowledgeandbeliefin accordancewith theRegulationsforElectricalInstallationspublishedby exceptfordepartures,if any,statedin thisCertificate.The extentof liabilityof thesignatoryis limitedto theworkdescribedaboveasthesubjectthis~rtificate.For theINSPECfION AND TEST of theinstallation:Name(inblockletters):For andon behalfof:Address:Position: Reg.No.I RECOMMEND thatthisinstallationbefurtherinspectedandtestedafteran intervalof notmorethan..........years.(2) Signature: (3)Date:!APPENDIX 2: FORMS OF COMPLETION AND INSPECTION CERTIFICATENOTE:1. This documentis intendedfor theinitialcertificationof a newinstallationor of an alterationoradditionto anexistinginstallationandof aninspection.2. Thesignaturesappendedarethoseof thepersonsauthorizedbythecompaniesexecutingtheworkofdesign.constructionandinspectionandtestingrespectively.A signatoryauthorizedtocertifymorethanonecategoryof workshallsignin eachof theappropriateplaces.SCHEDULE OF ADDITIONAL RECORDSETHIOPIAN BUILDING CODE STANDARD EBCS-101995 A-llTypeof Installation:Type of Earthing:PARTICULARS OF THE INSTALLATION(Deleteor completeitemsasappropriate)New/Alteration/Addition/to existinginstallationo TN-C 0 TN-S 0 TN-CS 0 IT 0 ITEarthElectrode: ResistanceMethodof MeasurementTypeandLocation.................ohmsCharacteristicsof thesupplyattheoriginof theinstallation:Nominalvoltage .............VoltsFrequency .............HzNumberof Phases .Prospectiveshort-circuitcurrentEarth faultloopimpedance(z.)................kA.................ohmsOvercurrentprotectivedevice: Type . Rating....A..Main switchor circuit-breaker Rating.....A . No of poles .(if anr.c.d.,ratedresidualoperatingcurrentIdB mA.)Methodof earthing:0 Cablesheath.o Additionaloverheadline conductoro Protectivemultipleearthing(p.M.E.)o Buriedstrip/rod/plateo Earth-leakagecircuit-breaker,voltageoperatedo Earth-leakagecircuit-breaker,currentoperatedThe impedanceof eachearth-continuityconductoris satisfactory:DYeso NoThe totalearth-loopimpedanceiso satisfactoryo unsatisfactoryfor readyoperationofthelargest-ratedexcess-currentprotectivedevicerelieduponfor earth-leakageprotection.Earth-leakageprotectionis affordedby a 0 current.-operated.o voltage-operatedearth-leakagecircuit-breaker,theoperationof whichis effective.APPENDIX 2: FORMS OF COMPLETION AND INSPECTION CERTIFICATEm.Polaritythroughouttheinstallationis correct DYeso NoAll single-polecontroldevicesarein liveconductorsonlyDYeso NoThe insulationresistanceof thefixedwiringinstallationis not lessthan1megohmDYeso NoThe insulationresistanceto earthof eachitemof apparatustestedseparatelyis notlessthan0.5megao]Eachitemof apparatustestedseparatelyis in goodserviceablecondition,exceptasstatedbelow.All flexiblecords,switches,fuses,plugsandsocket-outletsarein goodserviceablecop-dition,exceptasstatedbelow:Thereis no signof overloadingof conductorsor accessoriesexceptasstatedbelow.Apparatus tested o includes o doesnot include portableappliances.Comments(if any) and departuresfrom the WiriJilg Regulations:Signed Date: .For andonbehalfof: .....................................................................................................................................Address: ......................................................................................................................................................................................................ETHIOPIAN BUILDING CODE STANDARD EBCS-10 1995 A-13AAccessibility453Air blowerinstallation 459Air conditioning380Alarm signals346Ambienttemperature353Audibility of generalalarm 355Audiblealarmsprovidedbypublicaddressequipment356Audio transformer452Automaticrestartingafteroverload264Auxiliary equipment326Availableshort-circuitcurrent 145Avoidanceofflue -like openiJ).g358BBallastprotection327Bends376Bonding 169,171,451Bonding conductorsize 450,457,458Bondingmedium450Box 361Branchcircuitloadingandprotection333Branchcircuitovercurrentprotection260cCapacityof protectivegear 147Car lightingandaccessories380Ceiling 353Ceilingoutletboxwiring 325Chargingfacility 360Circuit connection360Circuit segregation455Clothesclosets 320Colourcoding 323Colourrenderingj7Commonearth430Communicationconductorsandcablesnotexceeding750V 448Component459Concrete- enclosedelectrode169Conduittype 455Conductorinstallation 375ConductorcrosssectionandInsulation324Conductorin buildingof combustibleconstruction357Conductoronmovableparts 324Conductorrun 376Conductors331Conductors- two ormoremotors258Conductorsattaclunent331Conductorscrosssection357Conductorsoperatingatnomorethan50k.v. 448Conductorsto individualmotors257Conduitseal 148Conduittodrain 148Connectionof conductors376Connectionof electrodes171Gonnectionpoint 359Connectionto supply 400Construction374Constructionandrequirements348Constructionofmessengercable333Continuityof earthingandbondingconductors171Continuousduty 384Controllocation267Control 327INDEXControlrequired266Controlswitches320Controls 457Controlslocation456Corrosion 192Coverings 414DDeckboxinstallation 451Deckboxes451Deepmoistclaysoil 191Design 346Detachedbuilding 147Detectortypes350Discrimination147Disruptiveelectricalinfluence358Drivingrodeelectrode170Dry - nicheluminaire453EEarthelectrodesealfor usewithinatankedstructure192Earthfaultcircuitbreakerlocation 457 .Earthrodconnection190Earth-faultcircuitinterrupter362Earth-leakageprotection146Earthedcontrolcircuit 267Earthingandbonding144E,arthingconductor/,0berunin a straightlille 430EarthingConductors430Earthingelectrode430Earthingof shields414Electriclifts 383Enclosedor guardedliveparts 144Equipment 385Equipmentandpowersupply 346Excessload 400Explosiveonflarnnlableatmosphere347Externalmetal 189FFaultsignaldiscrimination347Feederconductors259Feederovercurrentprotect261Feeding400Field- assembledunit 458Flooropenings353Floorprotectivecoverings414Flue-likeopenings351Formingshelltypes454Fusing 360GGeneral 145,188,190,326,328,331,347,348,349,354,360,373,397,413,448,449,450,452,454,456,457,458,356Grouping 143Groupingofmotorsonasinglebranchcircuit 261INDEXHHazard 327Heatbarrier 354Heightconsideration351Heightof conductor332Highestvoltag~358Hoistwaydoorinterlockingwiring 378Hydrauliclifts 383IIlluminance 37Illuminationlevel 387In hoistway,machineroomsandescalatorwellways379Independentmetalwaterpipes 168Installationandbonding458Installation 357,375,400,454,458Installationandtype 148lnstanteneoustripcircuitinterrupters262Insulation 429Insulationrating 378Insulationresistance356Internalmetal 189Interruption361JJ~ints 189Junctionboxbondingconductor450LLabelling 361Lampholders 326,332Lanternlights 351,353Laying 170Lengt11of cablefromtransformers376Lighting 386Lightingfixtures292Lightingfixtures 285,286,288,290Lightingswitch 387Linllts of spacing 352Live parts 321Location 145,451,452Locationoflightingequipment320Locationof thealarmcontrastandindicatingpanel 346Luminaire 387Luminaireprotection 453Luminaireasaraceway323Luminaireconstruction319Luminaireexposedto flyingobjects322Luminairein damporwetlocation320Luminairesupport453Luminaries 458MManualcall in automaticalarm 349Marking 143,374Material 318,429Materialforbondingconductors171Materialforsystemearthing171Meansof disconnect146Mechanicalandelectricalrequirements188Mechanicalprotection430Metalcarframesupportedbycables385Metalcasingof apump 169Metalparts 453Metersinstrumentsandrelays 284Minimumheightofluminaries322Monitoring 350Motorsupplyconductorinsulation,temperature257Motorsand generators 285,286,287289,2~1,293Motorsandgenerators285Motorsandgenerators286Motorsandgenerators287Motorsandgenerators289Motorsandgenerators293Multipleservices142NNearorovercombustiblematerial 320Non - continuousduty 384Numberandlocationof overloaddevices263NUmberofcircuitelement347oOn cars 379Opencore- andsoiltypetransformer375Originof call indication 348Other wiring 378Otherclasses454Otherfactors354Outletboxesto becovered322Outletdistance400Overcurrentprotection 146,327,362375Overloadandoverheatingprotection362Overcurrentprotectionmarkedonequipment260Overheatingprotectionrequired265Overheatingprotectionrequiredformotors265Overloadprotectionnotrequired264Overloadprotectionrequired 262pPendantconductors324Placement349Plateelectrode170Portablemotors257Positionrelativeto ceiling 351Protection 452,456Protectiondevicelocation 380Protectionofuninsulatedpart 374Provisionforbondingof futureequipment189Protection 319Publicwaterpipe 168RRateddurationof operation38Ratingandampacity257Ratingortripselectionofoverloaddevices 263Recessedluminaire 322Recessedluminairewiring 324Reinforcingsteel 449Remotelocation 361-~Responsetime 38Restrictedalanns 355Rodelectrode170sSandyor gravelysoil 191Secondaryconductors259Secondaryvoltage 374Sectionedrooms 351Segregation358.Segregation397Sequenceof control 147Serviceequipment328Shallowtopsoil 191Shortcircuitprotection362Showwindows 320Shuntingof overloadprotectionduringstarting 264Silencingswitch 355Singleservice 142Singletrussand north-lightroofs 353Sitingof safetyluminariesin hazardousworkspaces38Sizeofprotectiveearth 430Staircases351Sock~outlet 387,458Soillessthan0.3mdeeps 191Spacing 170Spacingandcrossing358Spacingfromcombustiblematerial332Spacingof conductors332Specialmonitoring351Splitknobs 331Startershavingdifferentsortingandrunningpositions 267Stationarymotors 257Storage- batterychargingequipment292Stricken 349Submersionqepth 452Suitability 357Supply 456Support 429Supports 321Switches,controllers,circuitbreakersandfuses 87,289,290,293Switches,motorcontrollers,circuitbreakersandfuses284Systemheights 414TThermalprotection326lbickness 374Timesswitch 456Transformer326Transformersandcapacitors 284,287,289,290,293Transformersusedoutdoors 375Transmissioncircuitry 347Travellingcables 378Troublesignal 398Two - stagealarm 355Typeof insulator 331Typesof conductors 376Typesof overheatingprotection265Typesof overloadprotection263uUndervoltageprotectiononfeedersorbranchcircuits 266Undervoltageprotectionrequiredformotors 265Use of insulators331Useof messengercables 333Usepermitted413Useprohibited413vVentilation 374Visualalarmsignal 356Voltage 31'),453Voltagedrop 399,400wWarningsign 454Wetnicheorsubmersibleluminaire 452Wiring 399Wiringmethods 285,286,287,289,291,293Wiringmethodsonpoler 328Wiringmethodsunderground 328Wiringoflighting equipment323wiringofluminaries 323Wiringof show-windowluminaries 325Workingspace 145INDEXCover PageForwordIntroductionTable of ContentsSection1-2Section3Section4-5Section 6-7Section 7Section 7(II)Section 8Section 9-10Section 11Section 12Section 13-14Section 15Section 16Section 17-18Section19Section 20-21Section 22-23Section 24Section 25Section 26SectionsSection 1-Scope and DefinitionsSection 2-General RequirementsSection 3 -Illumination Section 4-ConductorsSection 5-Equipment Section 6-Circuit Loading and Damage Factor Section 7-Earthing,Bonding,and Lightning Protection Section 7-Earthing,Bonding,and Lightning Protection (partII)Section 8-Wiring MethodsSection 9-Protection and Control Section 11-Installation of Electrical EquipmentSection10-Class 1and Class 2 Circuits Section 12- Hazardous LocationsSection 13-Flammable Liquid Dispensing and Service Stations,Garages,Bulk Storage Plants,Finishing Processes and Aircraft HandgarsSection 14-Patient Care AreasSection 15-Installation of Lighting EquipmentSection 16-Fire Alarm System and Fire PumpsSection 17-Signs and Outline LightingSection 18-Lifts,Escalators and Similar EquipmentSection 19-Theatre InstallationSection 20-Emergency Systems,Unit Equipment,and Exit Signs Section 21-Motion Picture Studios,Projection Rooms,Film Exchanges and FactoriesSection 22-Diagnostic Imaging InstallationSection 23-Electrical commuication SystemsSection 24-Community Antenna Installation for Radio and Television ReceptionSection 25-Swimming Pools,Fountains and Similar InstallationSection 26-Graphical SymbolsAppendices Appedix 1-Inspection and TestingAppendix 2-Forms of Completion and Inspection CertificateIndexA-GH-RS-W
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