saej1171v002

SAETechnicalStandardsBoardRulesprovidethat:“ThisreportispublishedbySAEtoadvancethestateoftechnicalandengineeringsciences.Theuseofthisreportisentirelyvoluntary,anditsapplicabilityandsuitabilityforanyparticularuse,includinganypatentinfringementarisingtherefrom,isthesoleresponsibilityoftheuser.”SAEreviewseachtechnicalreportatleasteveryfiveyearsatwhichtimeitmaybereaffirmed,revised,orcancelled.SAEinvitesyourwrittencommentsandsuggestions.Copyright©2004SAEInternationalAllrightsreserved.Nopartofthispublicationmaybereproduced,storedinaretrievalsystemortransmitted,inanyformorbyanymeans,electronic,mechanical,photocopying,recording,orotherwise,withoutthepriorwrittenpermissionofSAE.TOPLACEADOCUMENTORDER:Tel:877-606-7323(insideUSAandCanada)Tel:724-776-4970(outsideUSA)Fax:724-776-0790Email:custsvc@sae.orgSAEWEBADDRESS:http://www.sae.orgSURFACEVEHICLERECOMMENDEDPRACTICEJ1171REAF.JUN2004Issued1977-09Reaffirmed2004-06SupersedingJ1171JAN1986ExternalIgnitionProtectionofMarineElectricalDevices1.Scope—ThisSAERecommendedPracticecoversallelectricaldevicessuitableforuseinmarineenginecompartmentsandfueltankspaces.1.1Purpose—TorecommendatestprocedureforcertifyingtheExternalIgnitionProtectionofelectricaldevicesusedonboats.2.References—Therearenoreferencedpublicationsspecifiedherein.3.General—Adeviceshallnotproducecombustionbyexcessiveexternalsurfacetemperatureorbyaninternallygeneratedarc.Reproducibletestproceduresarenecessarytoensurethatneitherconditioncancauseexternalignitionwhentheparticularelectricaldeviceisbeingoperated.Inthefirstcase,whichinvolvesexcessiveexternalsurfacetemperatures,atestprocedureincludesoperationforaminimumtimeatahigher-than-ratedsystemvoltage(orcurrent)levelwithalimitingexternalsurfacetemperaturevalue.Thisshouldassurethatsuchadeviceisacceptableforuseinanenginecompartmentorfueltankspace.ThistestprocedureisdetailedinSection4.Inthesecondcase,whichinvolvesdevicescontainingpartscapableofarcing,twotestapproachesarenecessarysincesuchdevicesmaybeeithersealedornon-sealed.ThosethataresealedareExternalIgnitionProtectedbythefactthatacombustiblemixturecannotenterthevoidinwhichthearcoccurs.Therefore,thetestofsealeddevicesisatestofthesealintegrity.ThistestisdetailedinSection5.Non-sealeddevicesareExternalIgnitionProtectedwhentestsdemonstratethatignitionofacombustiblemixturewithinthedevicedoesnotcauseignitionofacombustiblemixturesurroundingthedevice.Thiswillbeverifiedby50deviceexplosionswiththeflammabilityofthemixturewithintheenclosingchamberbeingcheckedbyachamberexplosionaftereach10deviceexplosionsasdetailedinSection6.Thetestsequenceforanydeviceis:a.Section4—DeviceOperationb.Section5—SealedDevicesc.Section6—Non-SealedDevicesThisistoensurethatanydeficiencyintroducedinthedevicebytheOperationTestProcedure,suchassealdeterioration,etc.,canbedetectedinthefollowingtests.SAEJ1171ReaffirmedJUN2004-2-4.ContinuousDeviceOperationtoDetermineExternalSurfaceTemperatures4.1Electricaldevicesnotratedforcontinuousoperationandwiredwithmanuallyoperatedmomentaryswitchesareexemptfromthistestprocedure.Thisincludesdevicessuchasenginecrankingmotors,propulsionunittrimmotors,andotherintermittentlyoperateddevices.4.2Thistestshallberunwiththedeviceinanaircirculatingovenhavinganinitialtemperatureof60°C±2°C(140°F±4°F).4.3Thedeviceshallbeoperatedcontinuouslyforaminimumof7hinthemodeinwhichitdrawsitsmaximumcurrent.4.4Thetestvoltagesupplyshallbeadjustedto120%ofthenominalsystemvoltage(suchas12or115V).4.5Themaximumallowablesurfacetemperatureis200°C(392°F)measuredatanypointonthedevice’sexterior.5.MethodofTest—SealedDevices5.1EquipmentDescription—RefertoFigure1.FIGURE1—TESTASSEMBLY(SEALEDDEVICES)SAEJ1171ReaffirmedJUN2004-3-5.2TestProcedure5.2.1Submergethedevicetobetestedinachamberofwater,changingitsattitudeifnecessarysothatallpossiblesourcesofleaksareatthetopandare355mm±15mm(14in±0.5in)belowthesurfaceofthewater.Submergedtimeis15minforeachattitudechange.5.2.2Observethedeviceundertestcarefullyduringthetestdurationforaleakasevidencedbythegenerationofabubbleorstreamofbubbles.5.2.3Ifbubblesareobservedcomingoutoftheelectricalportionofthedevice,thedevicesshallnotbeconsideredasealeddeviceandshallbetestedunderSection6.5.2.4Ifnobubblesareobserved,removethedevicefromthewaterchamberanddryitsexterior.5.2.5Disassemblethedeviceforinternalinspection.5.2.6Ifnowaterisfoundinsidethedevice,itshallbeacceptedasexternalignitionprotected.Ifwaterisfound,itshallbetestedunderSection6.6.MethodofTest—Non-SealedDevices6.1EquipmentDescription—SeeFigures2and3.Specialnoteshouldbetakenofthepressure-relieflidarrangement.6.2DevicePreparation6.2.1Providemeansofintroducingacombustiblemixtureofpropaneandairintothedevicevia150mm(6in)minimumlengthofrigidorflexibletubinghavinganIDof1.5to6.35mm(1/16to1/4in),theselectiontobebasedontheminimumIDthatcanmaintainatestratewhichallowsaminimumoftwodeviceignitionsperminute.Thetubingsupplyingthemixturesamplefromthedevicetotheanalyzershallhavea1.5mm(1/16in)IDandaminimumlengthof150mm(6in).(UtilizingtheminimumIDminimizestheeffectofreducingthecombustionpressurewithinthedeviceatthetimeofignitionandmaximizestheseverityofthetest.)SeeFigure2.6.2.2Devicesthatdonotcontainopeningslargeenoughtopermittheintroductionofthemixtureattherequiredrateshallhaveaventintheformofacoppertubewitha150mm(6in)minimumlengthinstalledinthedevicewiththefreeendopentothechamber.TheIDofthecopperventshallbethesameasthatrequiredtofeedthedevice.NOTE—Thecoppermaterialisnecessarytoassurequenchingoftheflamebeforeitreachestheendopentothechamber.6.2.3Deviceswhicharetoosmallforthedirectinstallationofboththetubingfeedingthedeviceandthatsupplyingthedevicegasanalyzerrequireateefittingtojointhetubesfromwhichasingle150mm(6in)minimumlength,1.5mm(1/16in)ID,rigidorflexibletubingcanthenenterthedevice.SeeFigure3.6.2.4Thedevicecontactsoraseparatelymountedsparkplugorsparkplug-likeitemisrequiredtoprovideagapacrosswhichasparkcanjump.Thegapsizeneedonlybelargeenoughtoigniteconsistentlythespecifiedmixture.However,wherepossible,a2.54mm(0.100in)gapispreferred.Thesparkgapprovidedmustbeinstalledascloseaspossibletothatpartinthedevicefromwhichthearcwouldnormallyoriginate.Electricmotors,forexample,musthaveasparkplugmountedatthecommutatorendofthemotorsinceitisatthisendthatsparksbetweenthebrushesandcommutatorcanoccur.Thetestchamberignitionsystemshallbeasingle-shotsystemtoinsurethatthesurroundingmixtureiseasilyignitable.SAEJ1171ReaffirmedJUN2004-4-6.2.5Confirmationofignitionwithinthedevicecanusuallybedetectedbythenoiseproduced.Ifthe“pop”or“bang”isnotclearlyaudible,makeprovisionstocheckthepressureriseinthedeviceorutilizetheobservedflashofcombustionseenthrougha19mm(3/4in)maximumlength,6.35mm(1/4in)maximumIDsupplytubing.SeeFigure3.Thetransparenttubemustconnecttothedevicethroughaholelargeenoughtotransmitthecombustionintothetransparenttubewithoutbeingquenched.FIGURE2—TESTASSEMBLY(LARGENON-SEALEDDEVICES)SAEJ1171ReaffirmedJUN2004-5-FIGURE3—TESTASSEMBLY(SMALLNON-SEALEDDEVICES)SAEJ1171ReaffirmedJUN2004-6-6.3TestProcedure6.3.1Withthedeviceinthetestchamber,fillthedeviceandchamberwithmixturesasfollows:6.3.1.1TestChamber—Fillthetestchamberwithamixtureof4.75%±0.25%propanetoairbyvolume.Thistestchambermixtureratioistobemaintainedduringalltestingcycles.6.3.1.2Device—Fillthedevicewithamixtureratiodeterminedbyvaryingtheratiotoproduceamaximumpressureriseasindicatedbythepressuretransducer.Thismixtureratioshallthenbeusedthroughoutthedevicetestingprocedure.Wherethesmallestpracticablepressuretransducercannotbeinstalledduetothelimitedspaceavailable,amixtureratioof4.25%±0.25%propanetoairbyvolumeshallbeusedandcombustiondeterminedbytheflashofcombustionseenthroughthetransparenttubingsupplyingthepropane-airmixturetothedevice.SeeFigure3.6.3.2Afterestablishingthepropermixture,stopthefillingprocessandignitethedevicemixturewiththespark.NOTE—Ifanyattempttoignitethedevicemixturefails,purgethedeviceandchamberbyreturningtostep6.3.1andrerunonlythatcycle.DonotreruntheentireTest.6.3.3Confirmcombustioninthedevice.6.3.4Repeatsteps6.3.1to6.3.3nineadditionaltimesinsuccession.6.3.5Ignitethetestchambermixturewiththesingle-shotsparkaftereach10deviceignitionstoconfirmthatitishighlycombustible.NOTE—Ifanyattempttoignitethemixtureinthetestchamberfails,purgethedeviceandchamberandrepeatsteps6.3.1to6.3.3onlyforthat10cyclesegmentofthetestprocedure.Donotreruntheentiretest.6.3.6Repeatsteps6.3.1to6.3.5fouradditionaltimesinsuccession.Ifnoignitionofthetestchamberoccursasaresultofthedeviceignition(step6.3.2,)thedeviceshallbeconsideredtobeexternalignitionprotected.6.4SpecialNotesforNon-SealedDevices6.4.1CRANKINGMOTORS—Whentestingcrankingmotors,thepiniongearmustbeplacedinthepositionitwouldoccupywhenthemotorportionisenergized.Ifthemotorportionisenergizedwiththepinionretractedandextended,thecrankingmotormustbetestedwiththepinioninbothpositions.6.4.2DISTRIBUTORS—Modifythedistributorrotorcontacttoincreasethesparkgapto2.54mm(0.100in).Connectcomponentsasnecessarytoprovideasparkacrossthegap.Installahigh-tensionleadtoanyoneoftheremainingtowersandterminatetoground.Alignthedistributorrotorcontactwiththistower’selectrode.Includedinthedistributortestshallbefiveextended-firingcycles.Eachextended-firingcycleshallconsistofmaintainingthesparkforanadditional5minafterignitionofthedistributormixtureasdescribedin6.3.1to6.3.3.Ifthechambermixtureignites,thedistributorshallbeconsideredfailing.6.4.3INTRINSICSAFEDEVICES—SeeNote1in7.4.7.Marking7.1EvidenceofcompliancewiththerecommendedpracticeshallbeindicatedbythemarkingSAEJ1171togetherwiththewordMARINEarrangedinanysuitablemanner.Ifthespaceistoosmallforthiswording,thewordsmayappearonorinthesmallestpackagingofthedevice.SAEJ1171ReaffirmedJUN2004-7-7.2Responsibilityfordevicemarkingshallbenegotiablebetweenthecustomerandvendor.7.3Markingshouldbeaspermanentinnatureaspossible.7.4ServicereplacementpartsthatareessentialtoExternalIgnitionProtectionshouldbeidentifiedinthedevice’spartsbookasnecessarytoassureproperpartand/orassemblyreplacementinthefieldforcontinuingExternalIgnitionProtection.NOTE1—Anelectricaldevicewhichproduceslowenergysparksduringnormaloperationmaybeconsideredtobeanintrinsicallysafedevice.Anintrinsicallysafedeviceisdefinedasoneinwhichtheelectricalpowerflow,atthemaximumoperatingcondition,isatasufficientlylowlevelsuchthatthedevicecannot,inmanner,releaseanamountofthermalenergycapableofignitinggaseousmixtureasdefinedin6.3.1.1.Suchdevicesarenotnormallyexemptfromtestingperthisrecommendedpracticeforthefollowingreason:Thelevelofpowerflowingthroughanydeviceisdependentontheimpedanceofthedeviceitself,theimpedanceofthesharedcircuitcomponents,andonthesourceofelectricalpotential.Inaddition,inductive,capacitive,andvoltagevariationsplusmultipleinstallations,andparalleloperationcanallchangetheenergyflowthroughadevice.However,iftheparametersofuseareknown,unvarying,andthemaximumenergyconditionsarestrictlydefined,thephysicaltestofsuchadevicemaybewaived.Iftheabsolutemaximumreleaseofenergy,atthesparkingmemberswithinthedevice,isnogreaterthan0.24mJ,thedevicewillbeacceptableforuseinexplosiveatmospheres.PREPAREDBYTHESAEMARINEELECTRICALSYSTEMSSUBCOMMITTEEOFTHESAEMARINETECHNICALCOMMITTEESAEJ1171ReaffirmedJUN2004Rationale—ThisdocumenthasbeenreaffirmedtocomplywiththeSAE5-YearReviewpolicy.RelationshipofSAEStandardtoISOStandard—Notapplicable.Application—ThisSAERecommendedPracticecoversallelectricaldevicessuitableforuseinmarineenginecompartmentsandfueltankspaces.ReferenceSection—Therearenoreferencedpublicationsspecifiedherein.DevelopedbytheSAEMarineElectricalSystemsSubcommitteeSponsoredbytheMarineTechnicalCommittee