SAE-J1673-1996-HIGH-VOLTAGE-AUTOMOTIVE-WIRING-ASSE

SAETechnicalStandardsBoardRulesprovidethat:“ThisreportispublishedbySAEtoadvancethestateoftechnicalandengineeringsciences.Theuseofthisreportisentirelyvoluntary,anditsapplicabilityandsuitabilityforanyparticularuse,includinganypatentinfringementarisingtherefrom,isthesoleresponsibilityoftheuser.”SAEreviewseachtechnicalreportatleasteveryfiveyearsatwhichtimeitmaybereaffirmed,revised,orcancelled.SAEinvitesyourwrittencommentsandsuggestions.QUESTIONSREGARDINGTHISDOCUMENT:[phone]FAX:[phone]TOPLACEADOCUMENTORDER;[phone]FAX:[phone]SAEWEBADDRESS—ThisSAERecommendedPracticecoversthedesignandapplicationofprimaryon-boardwiringdistributionsystemharnessestoroadvehicles.Thisdocumentappliestoanywiringsystemwhichcontainsoneormorecircuitsoperatingbetween50VDCorACRMSand600VDCorACRMSexcludingautomotiveignitioncable.2.References2.1ApplicablePublications—Thefollowingpublicationsformapartofthisspecificationtotheextentspecifiedherein.Unlessotherwisespecified,thelatestissueofSAEpublicationsshallapply.2.1.1SAEPUBLICATIONS—AvailablefromSAE,400CommonwealthDrive,Warrendale,PA15096-0001.SAEJ163—LowTensionWiringandCableTerminalsandSpliceClipsSAEJ1127—BatteryCableSAEJ1128—LowTensionPrimaryCableSAEJ1292—Truck-Tractor,Trailer,andMotorCoachWiringSAEJ1654—HighVoltageCableSAEJ1742—ConnectionsforHighVoltageOn-BoardRoadVehicleElectricalWiring2.1.2ULPUBLICATION—AvailablefromUnderwriterLaboratoriesPublications,333PfingstenRoad,Northbrook,IL60062.UL1244—ElectricalandElectronicMeasuringandTestingEquipment2.2RelatedPublications—Thefollowingpublicationisprovidedforinformationpurposesonlyandisnotarequiredpartofthisdocument.2.2.1SAEPUBLICATION—AvailablefromSAE,400CommonwealthDrive,Warrendale,PA15096-0001.SAEJ2223—ConnectionsforOn-BoardRoadVehicleElectricalWiringHarnesses—Part1,Part2,Part3SAEJ1673IssuedJUL96-2-3.General3.1Definitions3.1.1CIRCUITPROTECTIONDEVICE—Afuse,circuitbreaker,PTCorNTC(PositiveThermalCoefficientorNegativeThermalCoefficient),intelligentcontactor,orotherdeviceplacedinanelectricalcircuittoprovidecurrentoverloadprotection.3.1.2HIGHVOLTAGE—Anywiringsystemwhichcontainsoneormorecircuitsoperatingbetween50VDCorACRMSand600VDCorACRMS.3.2InsulatedCable3.2.1Allinsulatedcablescarryingvoltagesgreaterthan50VDCorACRMSandlessthanorequalto600VDCorACRMSandwirecarryinglessthan50Vwhicharecombinedintothesameharnessbundlewithhighvoltage;wireshallconformtoSAEJ1654.3.2.2Selectcableinsulationinaccordancewiththevehicle’sworkingenvironment.Systemsmustallowforphysicalandenvironmentalfactorssuchasflexing,heat,cold,bend,fluidexposure,dielectric,abrasion,shortcircuit,andpinchresistanceamongothers.Somecableinsulationsexhibitthermoplasticcoldflowundercertainconditions.Careshouldbetakeninchoosingcablespassingthroughenvironmentalcablesealsorstrainreliefconnectorstopreventmoistureleaks.3.2.3SAEJ1127andJ1128specifynormalcablefluidexposuretestrequirements.Specificapplicationswilldictatewhethertheseoradditionalfluidcompatibilitytestsneedtobeadded.Failuremodesresultinginfluidexposuremustalsobeconsidered.3.2.4Itisdesirableforthewireofanyonecircuittobeofuniformcolorcodethroughoutthecircuitregardlessofthenumberofconnections.Acircuitisassumedtobecontinuousuntilitisinterruptedbyarelay,fuse,switchcontact,orwhenitreachesaload(suchasamotor,actuator,resistivedevice,etc.).3.2.5CABLESIZEDETERMINATION3.2.5.1Cablesizeisdeterminedbyconsideringthefollowingfactors:a.Maximumtemperatureriseaboveambientwithsteady-statecurrentoranticipateddutycyclesb.Maximumtemperatureriseinafaultconditioninpowerdistributioncircuitsc.Cablesizeappropriateforselectedconnectorsd.Cablemechanicalstrength3.2.5.2Themaximumsteady-statetemperatureshouldnotexceedthetemperatureratingofthewireinsulation,connectormaterial,orothermaterialswhichthecablemaycontact(itmaybepermissibletoexceedthetemperatureratingofthewireforshortperiodsoftimeperindividualmanufacturerspecifications).Amperecapacityofcablesisafunctionofmanyvariables.Someoftheseare:a.Conductorsize(gauge)b.Insulationmaterialc.Insulationwallthicknessd.Ambienttemperaturee.Proximitytoheatsinksandheatsourcesf.Wiringbundlesizeg.ConductormaterialSAEJ1673IssuedJUL96-3-3.2.5.3Cableselectionisdeterminedbyanalysisofthevehicleelectricalsystem.Abasicapproachisasfollows:a.Determinetheloadcharacteristicsofeachelectricalcomponentinthecircuit.Thismustincludesteady-statecurrentlevels,voltagerequirements,transientconditions,andcurrentlevelsandcurrentwaveformshape(steadyon,pulsed,frequency,etc.).Considerationmustbegiventomanufacturerre-ratingsbasedontheoperatingenvironment.b.Selecteachcircuitprotectiondevicesizebasedontotalloadcurrentandsomesafetymargintopreventinadvertentopeningundernormalconditions.Adeterminationmustalsobemadeastowhethercircuitprotectionphilosophywillbetoprotectt