SAETechnicalStandardsBoardRulesprovidethat:“ThisreportispublishedbySAEtoadvancethestateoftechnicalandengineeringsciences.Theuseofthisreportisentirelyvoluntary,anditsapplicabilityandsuitabilityforanyparticularuse,includinganypatentinfringementarisingtherefrom,isthesoleresponsibilityoftheuser.”SAEreviewseachtechnicalreportatleasteveryfiveyearsatwhichtimeitmaybereaffirmed,revised,orcancelled.SAEinvitesyourwrittencommentsandsuggestions.QUESTIONSREGARDINGTHISDOCUMENT:(724)772-8512FAX:(724)776-0243TOPLACEADOCUMENTORDER;(724)776-4970FAX:(724)776-0790SAEWEBADDRESS—ThisDocumenthasalsochangedtocomplywiththenewSAETechnicalStandardsBoardformat.1.Scope—ThisSAEStandarddefinesthetestconditions,procedures,andperformancerequirementsforcircuitbreakersinratingsuptoandincluding50A.Thedocumentincludesexternallyorinternallymountedautomaticreset,modifiedreset,andmanuallyresettypesofcircuitbreakersfor12Vand24VDCoperation.Somecircuitbreakersmayhavedualvoltageratings(ACandDC),however,thisdocumentevaluatesDCperformanceonly.2.References2.1ApplicablePublications—Thefollowingpublicationsformapartofthisspecificationtotheextentspecifiedherein.Unlessotherwisespecified,thelatestissueofSAEpublicationsshallapply.2.1.1SAEPUBLICATIONS—AvailablefromSAE,400CommonwealthDrive,Warrendale,PA15096-0001.SAEJ537—StorageBatteriesSAEJ561—ElectricalTerminals—EyeletandSpadeTypeSAEJ858a—ElectricalTerminals—BladeTypeSAEJ1171—ExternalIgnitionProtectionofMarineElectricalDevicesSAEJ1211—RecommendedEnvironmentalPracticesforElectronicEquipmentDesignSAEJ1428—MarineCircuitBreakersSAEJ1455—JointSAE/TMCRecommendedEnvironmentalPracticesforElectronicEquipmentDesign(Heavy-DutyTrucks)2.2RelatedPublications—Thefollowingpublicationsareprovidedforinformationpurposesonlyandarenotarequiredpartofthisdocument.2.2.1SAEPUBLICATIONS—AvailablefromSAE,400CommonwealthDrive,Warrendale,PA15096-0001.SAEJ258—CircuitBreaker—InternalMounted—AutomaticResetSAEJ554—ElectricFuses(CartridgeType)SAEJ1284—BladeTypeElectricFusesSAEJ1888—HighCurrentTimeLagElectricFusesSAETSB002—PreparationofSAETechnicalReportsSAEJ553RevisedAPR96-2-2.2.2CSAPUBLICATIONS—AvailablefromCSASalesDepartment,178RexdaleBoulevard,Etobtcoke,Ontario,M9W1R3.CSAC22.2No.14-M1987IndustrialControlEquipmentCSAC22.2No.235-M89SupplementaryProtectors2.2.3U.S.GOVERNMENTPUBLICATION—AvailablefromDODSSP,SubscriptionServicesDesk,Building4D,700RobbinsAvenue,Philadelphia,PA19111-5094.MIL-STD-202FTestMethodsforElectronicandElectricalComponentParts2.2.4UNDERWRITERLABORATORIESPUBLICATION—AvailablefromUnderwriterLaboratories,333PfingstenRoad,Northbrook,IL60062.U.L.1077—StandardforSupplementaryProtectorsforuseinElectricalEquipment2.2.5OTHERPUBLICATIONSNationalElectricCode—NECArticle551RecreationalVehicleIndustryAssociation—RVIAHandbook2.2.6APPENDICESAppendixACircuitProtectionApplicationGuidelinesAppendixBGlossaryofDocumentTerminology3.Definitions3.1CircuitBreakers—areovercurrentprotectivedevices,responsivetoelectriccurrentandtotemperature.3.2ExternallyMountedBreakers—aredefinedasself-containeddeviceswhicharemountedindividuallyorincombinationviabrackets,busbars,pluggedintoterminalblocks,orpanelmounted.3.3InternallyMountedBreakers—aredefinedassubcomponentdeviceswhichareintegralwitharelatedunitsuchasabreaker/switchcombination,withinamotorhousingformotorprotection,etc.Therearenoimpliedrestrictionsonpackagedesign,providedthethermalcircuitbreakerexhibitsperformancecharacteristicsandrangeofcurrentratingasiscoveredbythisdocument.Whileapplicationsaregenerallyfoundinmotorvehicleelectricalsystems,otherusagesinDCcircuitprotectionforaccessoriesrelatedorunrelatedtothemotorvehicleindustry,mayfindthisdocumentofvalueforperformanceevaluation.3.4Therearethreegeneralclassesofbreaker,definedasfollows:3.4.1TYPEI—AUTOMATICRESET—Automaticresetcircuitbreakersarecyclingorcontinuouslyself-resettingunitswhichareopenedbyovercurrent.3.4.2TYPEII—MODIFIEDRESET—Modifiedresetcircuitbreakersareunitswhichareopenedbyovercurrentsandremainopenaslongasthepowerisonoruntiltheloadisremoved.Anumberofcyclesmayoccurpriortoachievingthesteady-stateopencondition.3.4.3TYPEIII—MANUALRESET—Manualresetcircuitbreakersarenon-cyclingunitsthatareopenedbyovercurrents,butwhichremainopenuntilmanuallyreset.SAEJ553RevisedAPR96-3-4.TestRequirements4.1TestEquipmentandInstrumentation4.1.1POWERSUPPLIES4.1.1.1AcurrentandvoltageregulatedDCpowersupplyshallbeusedforalltestsexcept4.2.7InterruptTest.Thesupplyshallbecapableofdelivering14VDCand28VDCduringopencircuitportionoftestsandhavesufficientcurrentoutputcapacitytomeethighestloadrequirements.Voltageandcurrentsettingsshallbeaccuratetowithin±1%ofsetpointorbetter.Powertransientresponseshallbesuchthata30%stepincreaseinpowerdemandedbytheloadshallcauseatransientintheregulationoutput