ANSI IEEE C37.27-1987 IEEE Standard Application Gu

ANSI/IEEEC37.27-1987(RevisionofANSI/IEEEC37.27-1972)AnAmericanNationalStandardIEEEStandardApplicationGuideforLow-VoltageACNonintegrallyFusedPowerCircuitBreakers(UsingSeparatelyMountedCurrent-LimitingFuses)SponsorSwitchgearCommitteeoftheoftheIEEEPowerEngineeringSocietySecretariatInstituteofElectricalandElectronicsEngineersNationalElectricalManufacturersAssociationApprovedMay21,1981ReaffirmedJune18,1992IEEEStandardsBoardApprovedMay30,1986ReaffirmedJuly26,1993AmericanNationalStandardsInstitute©Copyright1987byTheInstituteofElectricalandElectronicsEngineers,Inc345East47thStreet,NewYork,NY10017,USANopartofthispublicationmaybereproducedinanyform,inanelectronicretrievalsystemorotherwise,withoutthepriorwrittenpermissionofthepublisher.iiIEEEStandardsdocumentsaredevelopedwithintheTechnicalCommitteesoftheIEEESocietiesandtheStandardsCoordinatingCommitteesoftheIEEEStandardsBoard.Membersofthecommitteesservevoluntarilyandwithoutcompensation.TheyarenotnecessarilymembersoftheInstitute.ThestandardsdevelopedwithinIEEErepresentaconsensusofthebroadexpertiseonthesubjectwithintheInstituteaswellasthoseactivitiesoutsideofIEEEwhichhaveexpressedaninterestinparticipatinginthedevelopmentofthestandard.UseofanIEEEStandardiswhollyvoluntary.TheexistenceofanIEEEStandarddoesnotimplythattherearenootherwaystoproduce,test,measure,purchase,market,orprovideothergoodsandservicesrelatedtothescopeoftheIEEEStandard.Furthermore,theviewpointexpressedatthetimeastandardisapprovedandissuedissubjecttochangebroughtaboutthroughdevelopmentsinthestateoftheartandcommentsreceivedfromusersofthestandard.EveryIEEEStandardissubjectedtoreviewatleastonceeveryfiveyearsforrevisionorreaffirmation.Whenadocumentismorethanfiveyearsold,andhasnotbeenreaffirmed,itisreasonabletoconcludethatitscontents,althoughstillofsomevalue,donotwhollyreflectthepresentstateoftheart.UsersarecautionedtochecktodeterminethattheyhavethelatesteditionofanyIEEEStandard.CommentsforrevisionofIEEEStandardsarewelcomefromanyinterestedparty,regardlessofmembershipaffiliationwithIEEE.Suggestionsforchangesindocumentsshouldbeintheformofaproposedchangeoftext,togetherwithappropriatesupportingcomments.Interpretations:Occasionallyquestionsmayariseregardingthemeaningofportionsofstandardsastheyrelatetospecificapplications.WhentheneedforinterpretationsisbroughttotheattentionofIEEE,theInstitutewillinitiateactiontoprepareappropriateresponses.SinceIEEEStandardsrepresentaconsensusofallconcernedinterests,itisimportanttoensurethatanyinterpretationhasalsoreceivedtheconcurrenceofabalanceofinterests.ForthisreasonIEEEandthemembersofitstechnicalcommitteesarenotabletoprovideaninstantresponsetointerpretationrequestsexceptinthosecaseswherethematterhaspreviouslyreceivedformalconsideration.Commentsonstandardsandrequestsforinterpretationsshouldbeaddressedto:Secretary,IEEEStandardsBoard345East47thStreetNewYork,NY10017USAiiiForeword(ThisForewordisnotapartofANSI/IEEEC37.27-1987,IEEEStandardApplicationGuideforLow-VoltageACNonintegrallyFusedPowerCircuitBreakers[UsingSeparatelyMountedCurrent-LimitingFuses].)ThispublicationisoneofaseriesofcomplementaryAmericanNationalStandards:ANSI/IEEEC37.13-1981,IEEEStandardforLow-VoltageACPowerCircuitBreakersUsedinEnclosuresANSI/IEEEC37.14-1979,IEEEStandardforLow-VoltageDCPowerCircuitBreakersUsedinEnclosuresANSIC37.16-1980,AmericanNationalStandardPreferredRatings,RelatedRequirements,andApplicationsRecommendationsforLow-VoltagePowerCircuitBreakersandACPowerCircuitProtectorsANSIC37.17-1979,AmericanNationalStandardTripDevicesforACandGeneralPurposeDCLow-VoltagePowerCircuitBreakersANSI/IEEEC37.18-1979,IEEEStandardEnclosedFieldDischargeCircuitBreakersforRotatingElectricMachineryANSI/IEEEC37.20-1969,IEEEStandardforSwitchgearAssembliesIncludingMetal-EnclosedBus(IncludesSupplementsANSI/IEEEC37.20a-1970,ANSI/IEEEC37.20b-1972,ANSI/IEEEC37.20c-1974,andANSI/IEEEC37.20d-1978)ANSI/IEEEC37.29-1981,IEEEStandardforLow-VoltageACPowerCircuitProtectorsUsedinEnclosuresThisapplicationguiderepresentsthestandardpracticeintheUnitedStatesrelatingtocombinationoflow-voltageacpowercircuitbreakers(seeANSI/IEEEC37.13-1981)andlow-voltageaccurrent-limitingcartridgefuses.Thisapplicationguidespecificallydoesnotcoverthecombinationofmoldedcasecircuitbreakersandlow-voltagecurrent-limitingfuses.Itdoescoverthecombinationoflow-voltageaircircuitbreakersandseparatelymountedcurrent-limitingfusesthattogetherfunctionasacoordinatedprotectivedevice.ItisthepolicyofboththeInstituteofElectricalandElectronicsEngineersandAmericanNationalStandardsAccreditedCommitteeC37tomaintainthisstandardcurrentwiththestateofthetechnology.Commentsonthisstandard,aswellassuggestionsforadditionalmaterialthatshouldbeincludedareinvited.Theseshouldbe-addressedtotheAmericanNationalStandardsInstitute,1430Broadway,NewYork,N.Y.10018,withcopytotheSecretaryIEEEStandardsBoardInstituteofElectricalandElectronicsEngineers,Inc345East47thStreetNewYork,N.Y.10017ivTheStandardsCommitteeonPowerSwitchgearC37,whichreviewedandapprovedthisstandard,hadthefollowingpersonnelatthetimeofapproval:W.E.Laub