UL 1434-2002 ISBN0-7629-294-9

热敏电阻UL标准UL1434
ISBN0-7629-294-9
Thermistor-TypeDevicesUnderwritersLaboratoriesInc.(UL)
333PfingstenRoad
Northbrook,IL60062-2096
ULStandardforSafetyforThermistor-TypeDevices,UL1434
FirstEdition,DatedApril3,1998
Revisions:ThisStandardcontainsrevisionsthroughandincludingAugust30,2002
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Copyright©2002UnderwritersLaboratoriesInc.
AUGUST30,2002−UL1434 tr2ThisStandardconsistsofpagesdatedasshowninthefollowingchecklist:
Page Date
1-5........................................................................... August30,2002
6.......................................................................... December15,2000
7-10 .......................................................................... August30,2002
11......................................................................... December15,2000
12-13 ......................................................................... August30,2002
14............................................................................... April3,1998
15-18 ...................................................................... December15,2000
19............................................................................ August30,2002
20-21 ...................................................................... December15,2000
22-24B........................................................................ August30,2002
25............................................................................... April3,1998
26......................................................................... December15,2000
27............................................................................ August30,2002
28............................................................................... April3,1998
29-30 ...................................................................... December15,2000
31-33 ......................................................................... August30,2002
34-35 ...................................................................... December15,2000
36-37 ......................................................................... August30,2002
38............................................................................... April3,1998
A1-A2 ............................................................................ April3,1998
AUGUST30,2002−UL1434 tr3AUGUST30,2002−UL1434 tr4
NoTextonThisPageAPRIL3,1998
(TitlePageReprinted:August30,2002)
1
UL1434
StandardforThermistor-TypeDevices
FirstEdition
April3,1998
Aneffectivedateincludedasanoteimmediatelyfollowingcertainrequirements
isoneestablishedbyUnderwritersLaboratoriesInc.
RevisionsofthisStandardwillbemadebyissuingrevisedoradditionalpages
bearingtheirdateofissue.AULStandardiscurrentonlyifitincorporatesthe
mostrecentlyadoptedrevisions,allofwhichareitemizedonthetransmittalnotice
thataccompaniesthelatestsetofrevisedrequirements.
ISBN0-7629-294-9
COPYRIGHT©2000,2002UNDERWRITERSLABORATORIESINC.AUGUST30,2002 THERMISTOR-TYPEDEVICES-UL1434 2
NoTextonThisPageCONTENTS
FOREWORD ................................................................................4
INTRODUCTION
1Scope ...............................................................................5
2General ..............................................................................6
2.1Components ...................................................................6
2.2Undatedreferences .............................................................6
2.3Unitsofmeasurement ...........................................................7
3Glossary .............................................................................7
CONSTRUCTION
4General .......................................................................... .12B
5ProtectionAgainstCorrosion ........................................................ .12B
6InsulatingMaterial ...................................................................13
7Spacings ............................................................................13
7.1Line-voltagecircuits ............................................................13
7.2Low-voltageandisolated-limited-energysecondarycircuits .........................15
8AlternativeSpacings–ClearancesandCreepageDistances ..............................16
9LiveParts ...........................................................................17
PERFORMANCE–PTCTHERMISTORS
10General ............................................................................17
11CalibrationTests ....................................................................19
11.1General .....................................................................19
11.2R/TmeasurementforPTCthermistors-alltypes ................................20
11.3R/TmeasurementforPTCheaters .............................................21
11.4Holdcurrent(Ih)testforPTCcurrentlimiters ....................................21
11.5Time-to-triptestforPTCcurrentlimiters .........................................22
11.6Surfacetemperaturetest .....................................................22
12AgingTest .........................................................................23
13Heat-Cold-HumidityCyclingTest .....................................................24
14OverloadTest .................................................................... .24A
15EnduranceTest .................................................................. .24A
16ColdOperationalCyclingTest ..................................................... .24B
17ColdThermalCyclingTest ........................................................ .24B
18LimitedShort-CircuitTest ............................................................25
18.1General .....................................................................25
18.2Primarycircuitapplications ....................................................25
18.3Otherthanprimarycircuitapplications ..........................................27
19ThermalRunawayTest ..............................................................27
20DielectricVoltage-WithstandTest(ForInsulatedThermistorsOnly) .......................27
AUGUST30,2002THERMISTOR-TYPEDEVICES-UL14342APERFORMANCE–NTCTHERMISTORS
21General ............................................................................28
22CalibrationTests ....................................................................29
22.1General .....................................................................29
22.2R/TmeasurementforNTCthermistors ..........................................30
22.3Surfacetemperaturetest(inrush-currentlimitingonly) ............................31
22.4Resistance(R25)andbetavalue(B)testforNTCthermistors ......................31
23AgingTest .........................................................................32
24Heat-Cold-HumidityCyclingTest .....................................................32
25OverloadTest ......................................................................34
26EnduranceTest ....................................................................34
27ColdOperationalCyclingTest ........................................................35
28ColdThermalCyclingTest ...........................................................36
29DielectricVoltage-WithstandTest(ForInsulatedThermistorsOnly) .......................36
MANUFACTURINGANDPRODUCTIONTESTS
30General ............................................................................36
RATING
31General ......................................................................... .36A
MARKING
32General ............................................................................38
APPENDIXA
StandardsforComponents..............................................................A1
AUGUST30,2002 THERMISTOR-TYPEDEVICES-UL1434 2BAUGUST30,2002THERMISTOR-TYPEDEVICES-UL14343
NoTextonThisPageFOREWORD
A.ThisStandardcontainsbasicrequirementsforproductscoveredbyUnderwritersLaboratoriesInc.(UL)
underitsFollow-UpServiceforthiscategorywithinthelimitationsgivenbelowandintheScopesection
ofthisStandard.Theserequirementsarebaseduponsoundengineeringprinciples,research,recordsof
testsandfieldexperience,andanappreciationoftheproblemsofmanufacture,installation,anduse
derivedfromconsultationwithandinformationobtainedfrommanufacturers,users,inspectionauthorities,
andothershavingspecializedexperience.Theyaresubjecttorevisionasfurtherexperienceand
investigationmayshowisnecessaryordesirable.
B.TheobservanceoftherequirementsofthisStandardbyamanufacturerisoneoftheconditionsofthe
continuedcoverageofthemanufacturer’sproduct.
C.AproductwhichcomplieswiththetextofthisStandardwillnotnecessarilybejudgedtocomplywith
theStandardif,whenexaminedandtested,itisfoundtohaveotherfeatureswhichimpairthelevelof
safetycontemplatedbytheserequirements.
D.Aproductthatcontainsfeatures,characteristics,components,materials,orsystemsnewordifferent
fromthosecoveredbytherequirementsinthisstandard,andthatinvolvesariskoffireorofelectricshock
orinjurytopersonsshallbeevaluatedusingappropriateadditionalcomponentandend-product
requirementstomaintainthelevelofsafetyasoriginallyanticipatedbytheintentofthisstandard.A
productwhosefeatures,characteristics,components,materials,orsystemsconflictwithspecific
requirementsorprovisionsofthisstandarddoesnotcomplywiththisstandard.Revisionofrequirements
shallbeproposedandadoptedinconformancewiththemethodsemployedfordevelopment,revision,and
implementationofthisstandard.
E.UL,inperformingitsfunctionsinaccordancewithitsobjectives,doesnotassumeorundertaketo
dischargeanyresponsibilityofthemanufactureroranyotherparty.TheopinionsandfindingsofUL
representitsprofessionaljudgmentgivenwithdueconsiderationtothenecessarylimitationsofpractical
operationandstateoftheartatthetimetheStandardisprocessed.ULshallnotberesponsibletoanyone
fortheuseoforrelianceuponthisStandardbyanyone.ULshallnotincuranyobligationorliabilityfor
damages,includingconsequentialdamages,arisingoutoforinconnectionwiththeuse,interpretationof,
orrelianceuponthisStandard.
F.ManytestsrequiredbytheStandardsofULareinherentlyhazardousandadequatesafeguardsfor
personnelandpropertyshallbeemployedinconductingsuchtests.
AUGUST30,2002 THERMISTOR-TYPEDEVICES-UL1434 4INTRODUCTION
1Scope
1.1Theserequirementsapplytodiscretethermistor-typedevicesconstructedofceramicorpolymeric
semiconductormaterial.
1.1effectiveApril3,2000
1.2Thesethermistorsareintendedforuseas:
a)Self-limitingdevicessuchasheaters;
b)Controldevicessuchascurrentlimitersandinrush-currentlimiters;or
c)Sensingdevices.
1.2effectiveApril3,2000
1.3Theserequirementsapplytopositivetemperaturecoefficient(PTC)andnegativetemperature
coefficient(NTC)typedevices.
1.3effectiveApril3,2000
1.4Controldevices,suchascurrentlimitersarenotintendedtoreplacecurrentinterruptingdevicessuch
asfuses,butareintendedtoprovidealevelofovercurrentprotectioncomplyingwiththeend-use
equipmentrequirements.
1.4effectiveApril3,2000
1.5Theserequirementsdonotapplytoheatingcables,suchasself-regulatingpipeheatingcable,that
areconstructedwiththermistor-typematerial.
1.5effectiveApril3,2000
1.6DeletedAugust30,2002
AUGUST30,2002THERMISTOR-TYPEDEVICES-UL143452General
2.1Components
2.1.1Exceptasindicatedin2.1.2,acomponentofaproductcoveredbythisstandardshallcomplywith
therequirementsforthatcomponent.SeeAppendixAforalistofstandardscoveringcomponentsused
intheproductscoveredbythisstandard.
2.1.1effectiveApril3,2000
2.1.2Acomponentisnotrequiredtocomplywithaspecificrequirementthat:
a)Involvesafeatureorcharacteristicnotrequiredintheapplicationofthecomponentinthe
productcoveredbythisstandard,or
b)Issupersededbyarequirementinthisstandard.
2.1.2revisedDecember15,2000
2.1.3Acomponentshallbeusedinaccordancewithitsratingestablishedfortheintendedconditionsof
use.
2.1.3effectiveApril3,2000
2.1.4Specificcomponentsareincompleteinconstructionfeaturesorrestrictedinperformance
capabilities.Suchcomponentsareintendedforuseonlyunderlimitedconditions,suchascertain
temperaturesnotexceedingspecifiedlimits,andshallbeusedonlyunderthosespecificconditions.
2.1.4effectiveApril3,2000
2.1.5DeletedDecember15,2000
2.1.6DeletedDecember15,2000
2.1.7DeletedDecember15,2000
2.2Undatedreferences
2.2.1Anyundatedreferencetoacodeorstandardappearingintherequirementsofthisstandardshall
beinterpretedasreferringtothelatesteditionofthatcodeorstandard.
2.2.1effectiveApril3,2000
DECEMBER15,2000 THERMISTOR-TYPEDEVICES-UL1434 62.3Unitsofmeasurement
2.3.1Valuesstatedwithoutparenthesesaretherequirement.Valuesinparenthesesareexplanatoryor
approximateinformation.
2.3.1revisedDecember15,2000
3Glossary
3.1Forthepurposeofthisstandard,thefollowingdefinitionsapply.
3.1effectiveApril3,2000
3.2AMBIENT,ROOM–25 ±2°C(77 ±3.6°F)orasspecifiedbythemanufacturer.
3.2effectiveApril3,2000
3.3BVALUE–ANTCthermistor’sindex,whichexpressesthedegreeofresistancechangewhen
calculatedfromanytwopointsspecifiedbythemanufacturerontheresistance/temperature(R/T)curve.
3.3revisedAugust30,2002
3.4CIRCUIT,ISOLATED-LIMITED-ENERGYSECONDARY–Acircuitderivedfromanisolated
secondarywindingofatransformerhavingamaximumcapacityof100volt-amperesandanopen-
circuitsecondaryvoltageratingnotexceeding1000volts.Acircuitderivedfromaline-voltagecircuitby
connectingresistanceinserieswiththesupplycircuitasameansoflimitingthevoltageandcurrentis
notanisolated-limited-energysecondarycircuit.
3.4effectiveApril3,2000
3.5CIRCUIT,LINE-VOLTAGE–Acircuitinvolvingapotentialofnotmorethan600voltsandhaving
circuitcharacteristicsinexcessofalow-voltageorisolated-limited-energysecondarycircuit.
3.5effectiveApril3,2000
3.6CIRCUIT,LOW-VOLTAGE–Acircuitinvolvingapotentialofnotmorethan30volts(42.4volts
peak)or60voltsdcandsuppliedbyaprimarybattery,byastandardClass2transformer,orbya
combinationofatransformerandacurrentlimitingimpedancethat,asaunit,complieswithallthe
performancerequirementsforaClass2transformer.Acircuitderivedfromaline-voltagecircuitby
connectingresistanceinserieswiththesupplycircuitasameansoflimitingthevoltageandcurrentis
notalow-voltagecircuit.
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