IEC61462:2023-09(en-fr)

IEC61462

?

Edition2.0 2023-09

INTERNATIONALSTANDARD

NORMEINTERNATIONALE

Compositehollowinsulators–PressurizedandunpressurizedinsulatorsforuseinelectricalequipmentwithACratedvoltagegreaterthan1000VACandD.C.voltagegreaterthan1500V–Definitions,testmethods,acceptancecriteriaanddesignrecommendations

Isolateurscompositescreux–Isolateursavecousanspressioninternepourutilisationdansdesappareillagesélectriquesdetensionsalternativesassignéessupérieuresà1000Vetdetensionscontinuessupérieuresà1500V–Définitions,méthodesd’essai,critèresd’acceptationetrecommandationsdeconception

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IEC61462

?

Edition2.0 2023-09

INTERNATIONALSTANDARD

NORMEINTERNATIONALE

–

PAGE

100

–

IEC61462:2023?IEC2023

Compositehollowinsulators–PressurizedandunpressurizedinsulatorsforuseinelectricalequipmentwithACratedvoltagegreaterthan1000VACandD.C.voltagegreaterthan1500V–Definitions,testmethods,acceptancecriteriaanddesignrecommendations

Isolateurscompositescreux–Isolateursavecousanspressioninternepourutilisationdansdesappareillagesélectriquesdetensionsalternativesassignéessupérieuresà1000Vetdetensionscontinuessupérieuresà1500V–Définitions,méthodesd’essai,critèresd’acceptationetrecommandationsdeconception

INTERNATIONALELECTROTECHNICALCOMMISSION

COMMISSIONELECTROTECHNIQUEINTERNATIONALE

ICS29.080.10 ISBN978-2-8322-7403-3

Warning!Makesurethatyouobtainedthispublicationfromanauthorizeddistributor.

Attention!Veuillezvousassurerquevousavezobtenucettepublicationviaundistributeuragréé.

?RegisteredtrademarkoftheInternationalElectrotechnicalCommissionMarquedéposéedelaCommissionElectrotechniqueInternationale

CONTENTS

FOREWORD 5

INTRODUCTION 7

Scope 8

Normativereferences 9

Termsanddefinitions 9

Relationshipsofmechanicalloads 13

Loadsfromoutsidetheinsulator 13

Pressures 13

Marking 14

Classificationoftests 14

General 14

Designtests 14

Typetests 16

Sampletests 16

Routinetests 16

Designtests 17

General 17

Testsoninterfacesandconnectionsofendfittings 17

General 17

Testspecimen 17

Referencedisruptive–dischargedrypowerfrequencytest 17

Thermal-mechanicalpre-stressingtest 17

Waterimmersionpre-stressingtest 18

Verificationtests 18

Testsonshedandhousingmaterial 19

Hardnesstest 19

Acceleratedweatheringtest 19

Trackinganderosiontest–1000hsaltfogACvoltagetest 19

Flammabilitytest 19

Hydrophobicitytransfertest 19

Testsonthetubematerial 19

General 19

Porositytest(Dyepenetrationtest) 20

Waterdiffusiontest 20

Waterdiffusiontestoncorewithhousing 20

Typetests(onlymechanicaltests) 20

General 20

Testspecimens 20

Preparationofthetestspecimen 21

Internalpressuretest 22

General 22

Testprocedure 22

Acceptancecriteria 23

Bendingtest 23

General 23

Testprocedure 23

Acceptancecriteria 24

Sampletests 24

Selectionandnumberofinsulators 24

Testing 25

Verificationofdimensions 25

Testprocedure 25

Acceptancecriteria 25

Mechanicaltests 25

General 25

Testprocedure 25

Acceptancecriteria 26

Galvanizingtest 26

Re-testprocedure 26

Routinetests 27

General 27

Visualexamination 27

Routinemechanicaltest 27

Routinepressuretest 27

Routinetightnesstest 28

Documentation 28

AnnexA(normative)Tolerancesofformandposition 33

AnnexB(informative)Generalrecommendationsfordesignandconstruction 36

Guidancefordesign 36

Guidanceforthemaximumservicepressure 36

Guidanceonsampletestingoftubematerial 36

Guidanceforthetemperaturerequiredbytheequipmentmanufacturer 37

Guidanceforthemechanicalloadsrequiredbytheequipmentmanufacturer 37

Summaryofthetests 37

AnnexC(informative)Principlesofdamagelimitanduseofreversibleandirreversible

straincausedbyinternalpressureand/orbendingloadsoncompositehollowinsulator

tubes 41

Overview 41

Definition 41

Exampleofdeterminingthestraintolerance 41

AnnexD(informative)Principlesketchofhollowinsulatorsdesignassembly 44

AnnexE(informative)Typetestsontapered(conical)insulators 46

General 46

Minimumlengthonthemoststressedcylindricalpartsonshortenedtest

specimens 46

Internalpressuretest 47

Bendingtest 47

References 49

Bibliography 50

Figure1–Thermal-mechanicalpre-stressingtest–Typicalcycles 29

Figure2–Thermal-mechanicalpre-stressingtest–Typicaltestarrangement 30

Figure3–Testarrangementfortheleakageratetest 31

Figure4–Examplesofsealingsystemsforcompositehollowinsulators 32

IEC61462:2023?IEC2023

–

PAGE

11

–

–

PAGE

4

–

IEC61462:2023?IEC2023

FigureA.1–Parallelism,coaxialityandconcentricity 33

FigureA.2–Angulardeviationoffixingholes:Example1 34

FigureA.3–Angulardeviationoffixingholes:Example2 34

FigureA.4–Tolerancesaccordingtostandarddrawingpractice 35

FigureB.1–Relationshipofbendingloads 40

FigureB.2–Relationshipofpressures 40

FigureC.1–Positionofstraingaugesforpressureloadandbendingload 42

FigureC.2–Strain/timecurve,reversibleelasticphase 42

FigureC.3–Strain/timecurve,irreversibleplasticphase,damagelimit 43

FigureD.1–Interfacedescriptionforinsulatorwithhousingmadebymodular

assembly 44

FigureD.2–Interfacedescriptionforinsulatorwithhousingmadebyinjectionmolding

andovermoldedendfitting 45

FigureE.1–Illustrationoftaperedinsulatorsinbending 47

FigureE.2–Illustrationofaxialmembranestressalongtheinsulatorwhenthelength

ofthecylindricalpartsischanged 48

Table1–Mechanicalloadsappliedtotheinsulator 13

Table2–Pressuresappliedtotheinsulator 13

Table3–Teststobecarriedoutafterdesignchanges 15

Table4–Samplesizes 24

Table5–Choiceofre-testprocedure 26

TableB.1–Loads/stressandclassificationoftests 38

TableB.2–Exampleofpressure/bendingvalues–Practicalrelationshipofthevalues 39

INTERNATIONALELECTROTECHNICALCOMMISSION

COMPOSITEHOLLOWINSULATORS–

PRESSURIZEDANDUNPRESSURIZEDINSULATORSFORUSE

INELECTRICALEQUIPMENTWITHACRATEDVOLTAGEGREATERTHAN1000VANDDCVOLTAGEGREATERTHAN1500V–

DEFINITIONS,TESTMETHODS,ACCEPTANCECRITERIAANDDESIGNRECOMMENDATIONS

FOREWORD

TheInternationalElectrotechnicalCommission(IEC)isaworldwideorganizationforstandardizationcomprisingallnationalelectrotechnicalcommittees(IECNationalCommittees).TheobjectofIECistopromoteinternationalco-operationonallquestionsconcerningstandardizationintheelectricalandelectronicfields.Tothisendandinadditiontootheractivities,IECpublishesInternationalStandards,TechnicalSpecifications,TechnicalReports,PubliclyAvailableSpecifications(PAS)andGuides(hereafterreferredtoas"IECPublication(s)").Theirpreparationisentrustedtotechnicalcommittees;anyIECNationalCommitteeinterestedinthesubjectdealtwithmayparticipateinthispreparatorywork.International,governmentalandnon-governmentalorganizationsliaisingwiththeIECalsoparticipateinthispreparation.IECcollaboratescloselywiththeInternationalOrganizationforStandardization(ISO)inaccordancewithconditionsdeterminedbyagreementbetweenthetwoorganizations.

TheformaldecisionsoragreementsofIEContechnicalmattersexpress,asnearlyaspossible,aninternationalconsensusofopinionontherelevantsubjectssinceeachtechnicalcommitteehasrepresentationfromallinterestedIECNationalCommittees.

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AttentionisdrawntotheNormativereferencescitedinthispublication.Useofthereferencedpublicationsisindispensableforthecorrectapplicationofthispublication.

AttentionisdrawntothepossibilitythatsomeoftheelementsofthisIECPublicationmaybethesubjectofpatentrights.IECshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.

IEC61462hasbeenpreparedbyIECtechnicalcommittee36:Insulators.ItisanInternationalStandard.

Thisneweditioncancelsandreplacesthepreviouseditionpublishedin2007.Thiseditionconstitutesatechnicalrevision.

Thiseditionincludesthefollowingsignificanttechnicalchangeswithrespecttothepreviousedition:

modificationsoftermsanddefinitions;

modificationsoftestsproceduresincludedinIECTR62039andIEC62217(Hydrophobicitytransfertest;Waterdiffusiontestonthecorewithhousing);

modificationofClause

8

(typetests)toreflectcommonpracticeandtoalsoconsidertapered(conical)insulators;

modificationoforderofthestagesofmechanicalsampletest(

9.4

)bysettingthetightnesstestaslaststage;

harmonizationof

Table3

(Teststobecarriedoutafterdesignchanges)withotherproductstandards;

additionofanewinformative

AnnexD:

Principlesketchofhollowinsulatorsdesignassembly;

additionofanewinformative

AnnexE:

Typetestsontapered(conical)insulators.ThetextofthisInternationalStandardisbasedonthefollowingdocuments:

Draft

Reportonvoting

36/567/FDIS

36/586/RVD

Fullinformationonthevotingforitsapprovalcanbefoundinthereportonvotingindicatedintheabovetable.

ThelanguageusedforthedevelopmentofthisInternationalStandardisEnglish.

ThisdocumentwasdraftedinaccordancewithISO/IECDirectives,Part2,anddevelopedinaccordancewithISO/IECDirectives,Part1andISO/IECDirectives,IECSupplement,availableat

www.iec.ch/members_experts/refdocs.

ThemaindocumenttypesdevelopedbyIECaredescribedingreaterdetailat

www.iec.ch/publications.

ThecommitteehasdecidedthatthecontentsofthisdocumentwillremainunchangeduntilthestabilitydateindicatedontheIECwebsiteunderwebstore.iec.chinthedatarelatedtothespecificdocument.Atthisdate,thedocumentwillbe

reconfirmed,

withdrawn,

replacedbyarevisededition,or

amended.

INTRODUCTION

Compositehollowinsulatorsconsistofaninsulatingtubebearingthemechanicalloadprotectedbyanelastomerichousing,theloadsbeingtransmittedtothetubebymetalfittings.Despitethesecommonfeatures,thematerialsusedandtheconstructiondetailsemployedbydifferentmanufacturersmayvary.

Sometestshavebeengroupedtogetheras"Designtests"tobeperformedonlyonceforinsulatorsofthesamedesignandmaterial.Thedesigntestsareperformedinordertoeliminatedesignsandmaterialsnotsuitableforhigh-voltageapplications.

TherelevantdesigntestsdefinedinIEC62217areappliedforcompositehollowinsulators;additionalspecificmechanicaltestsaregiveninthisdocument.Theinfluenceoftimeontheelectricalandmechanicalpropertiesofthecompletecompositehollowinsulatoranditscomponents(tubematerial,housingmaterial,interfaces,etc.)hasbeenconsideredinspecifyingthedesigntestsinordertoensureasatisfactorylifetimeundernormalserviceconditions.Theseconditionsmayalsodependontheequipmentinsideoroutsidethecompositehollowinsulators;however,thismatterhasnotbeencoveredinthisdocument.Itispossiblefortestmethodsnotspecifiedinthisdocumenttobeconsideredforspecificcombinationsofmaterialsandspecificapplications,andareamatterofagreementbetweenmanufacturersandusers.Inthisdocument,theterm"user"ingeneralmeanstheequipmentmanufacturerusingcompositehollowinsulators.

CompositehollowinsulatorsareusedinbothACandDCapplications.BeforetheappropriatestandardforDCapplicationswillbeissued,themajorityoftestslistedinthisdocumentcanalsobeappliedtoDCinsulators.Inspiteofthis,aspecifictrackinganderosiontestprocedureforDCapplicationsasadesigntestisstillbeingconsideredtobedeveloped.SomeinformationaboutthedifferenceofACandDCmaterialerosiontestcanbefoundintheCIGRETechnicalBrochure611.Forthetimebeing,the1000hACtrackinganderosiontestofIEC62217isusedtoestablishaminimumrequirementforthetrackinganderosionresistance,forbothACandDC

Thisdocumentdistinguishesbetweendesigntestsandtypetestsbecauseseveralgeneralcharacteristicsofaspecificdesignandspecificcombinationsofmaterialsdonotvaryfordifferentinsulatortypes.Inthesecasesresultsfromdesigntestscanbeadoptedfordifferentinsulatortypes.

PollutiontestsaccordingtoIEC60507orIEC61245arenotincludedinthisdocumentsincetheyaredesignedfornon-polymericitems.Specificpollutiontestsforpolymericinsulatorsarestillunderconsideration.

Themechanicalcharacteristicsofcompositehollowinsulatorsarequitedifferentcomparedtothoseofhollowinsulatorsmadeofceramics.Inordertodeterminetheonsetofmechanicaldeteriorationofcompositehollowinsulatorsundertheinfluenceofmechanicalstress,straingaugemeasurementsareused.

Thisdocumentreferstodifferentcharacteristicpressureswhichareusedfordesignandtestingofcompositehollowinsulators.Theterm"maximumservicepressure"(MSP)isequivalenttotheterm"designpressure"whichisusedinotherstandardsforceramichollowinsulators;however,thislattertermisnotusedinthisstandardinordertoavoidconfusionwith"design"asusedin"designtests".

Generalrecommendationsforthedesignandconstructionofcompositehollowinsulatorsarepresentedin

AnnexB.

COMPOSITEHOLLOWINSULATORS–

PRESSURIZEDANDUNPRESSURIZEDINSULATORSFORUSE

INELECTRICALEQUIPMENTWITHACRATEDVOLTAGEGREATERTHAN1000VANDDCVOLTAGEGREATERTHAN1500V–

DEFINITIONS,TESTMETHODS,ACCEPTANCECRITERIAANDDESIGNRECOMMENDATIONS

Scope

Thisdocument,whichisanInternationalStandard,appliestocompositehollowinsulatorsconsistingofaload-bearinginsulatingtubemadeofresinimpregnatedfibres,ahousing(outsidetheinsulatingtube)madeofelastomericmaterial(forexamplesiliconeorethylene-propylene)andmetalfixingdevicesattheendsoftheinsulatingtube(see

FigureD.1

and

FigureD.2

forexamples).Compositehollowinsulatorsasdefinedinthisdocumentareintendedforgeneraluse(unpressurized)orforusewithapermanentgaspressure(pressurized).Theyareintendedforuseinbothoutdoorandindoorelectricalequipmentoperatingonalternatingcurrentwitharatedvoltagegreaterthan1000VACandafrequencynotgreaterthan100Hzorforuseindirectcurrentequipmentwitharatedvoltagegreaterthan1500VDC.

Theobjectofthisdocumentis:

todefinethetermsused;

tospecifytestmethods;

tospecifyacceptancecriteria.

Hollowinsulatorsareintegratedintoelectricalequipmentwhichiselectricallytypetestedasrequiredbytheapplicableequipmentstandard.So,itisnottheobjectofthisdocumenttospecifydielectrictypetestsbecausethewithstandvoltagesandflashoverbehaviourarenotcharacteristicsofthehollowinsulatoritselfbutoftheapparatusofwhichitultimatelyformsapart.

Allthetestsinthisdocument,apartfromthethermal-mechanicaltest,areperformedatnormalambienttemperature.Thisdocumentdoesnotspecifyteststhatmightbecharacteristicoftheequipmentofwhichthehollowinsulatorultimatelyformsapart.

Compositehollowinsulatorsareintendedforuseinelectricalequipment,suchas,butnotlimitedto:

HVcircuit-breakers,

switch-disconnectors,

disconnectors,

stationposts,

disconnectingcircuitbreakers,

earthingswitches,

instrument-andpowertransformers,

bushings,

housingforsurgearresters,

cableterminations.

AdditionaltestingdefinedbytherelevantIECequipmentstandardmayberequired.

Normativereferences

Thefollowingdocumentsarereferredtointhetextinsuchawaythatsomeoralloftheircontentconstitutesrequirementsofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.

IEC62155,Hollowpressurizedandunpressurizedceramicandglassinsulatorsforuseinelectricalequipmentwithratedvoltagesgreaterthan1000V

IEC62217,PolymericHVinsulatorsforindoorandoutdooruse–Generaldefinitions,testmethodsandacceptancecriteria

IECTR62039,SelectionguidelinesforpolymericmaterialsforoutdooruseunderHVstress

Termsanddefinitions

Forthepurposesofthisdocument,thefollowingtermsanddefinitionsapply.

ISOandIECmaintainterminologicaldatabasesforuseinstandardizationatthefollowingaddresses:

IECElectropedia:availableat

/

ISOOnlinebrowsingplatform:availableat

/obp

3.1

compositehollowinsulator

insulatorconsistingofatleasttwoinsulatingparts,namelyatubeandahousing

Note1toentry:Thehousingmayconsisteitherofindividualshedsmountedonthetube,withorwithoutanintermediatesheath,ordirectlyappliedinoneorseveralpiecesontothetube.Acompositehollowinsulatorunitispermanentlyequippedwithfixingdevicesorendfittings

3.2

tube(core)

centralinternalinsulatingpartofacompositehollowinsulatorwhichprovidesthemechanicalcharacteristics

Note1toentry:Thehousingandshedsarenotpartofthecore.

Note2toentry:Thetubeisgenerallycylindricalorconical,butmayhaveothershapes(forexamplebarrel).Thetubeismadeofresinimpregnatedfibres.

Note3toentry:Resinimpregnatedfibresarestructuredinsuchamannerastoachievesufficientmechanicalstrength.Layersofdifferentfibresmaybeusedtofulfilspecialrequirements.

[SOURCE:IEC60050-471:2007,471-01-03,modified–additionof"tube"interm,additionof"internal",additionof"compositehollow",additionofNotes2and3toentry]

3.3

fixingdeviceendfitting

integralcomponentorformedpartofaninsulator,intendedtoconnectittoasupportingstructure,ortoaconductor,ortoanitemofequipment,ortoanotherinsulator

Note1toentry:Wheretheendfittingismetallic,theterm"metalfitting"isnormallyused.

[SOURCE:IEC60050-471:2007,471-01-06,modified–additionof"fixingdevice"interm]

3.4

coupling

partofthefixingdevicewhichtransmitsloadtothehardwareexternaltotheinsulator[SOURCE:IEC62217:2012,3.14]

3.5

connectionzone

zonewherethemechanicalloadistransmittedbetweentheinsulatingbodyandtheendfitting[SOURCE:IEC62217:2012,3.13]

3.6

housing

externalinsulatingpartofcompositehollowinsulatorprovidingnecessarycreepagedistanceandprotectingtubefromenvironment

Note1toentry:Ifanintermediatesheathisuseditformsapartofthehousing.

[SOURCE:IEC62217:2012,3.7]

[SOURCE:IEC60050-471:2007,471-01-09,modified–additionof"hollow",replacementof"core"by"tube"]

3.7

shed(ofaninsulator)

insulatingpart,projectingfromtheinsulatortrunk,intendedtoincreasethecreepagedistance

Note1toentry:Theshedcanbewithorwithoutribs.

[SOURCE:IEC60050-471:2007,471-01-15]

3.8

insulatortrunk

centralinsulatingpartofaninsulatorfromwhichtheshedsproject

Note1toentry:Alsoknownasshankonsmallerinsulators.

[SOURCE:IEC60050-471:2007,471-01-11]

3.9

creepagedistance

shortestdistanceorthesumoftheshortestdistancesalongthesurfaceonaninsulatorbetweentwoconductivepartswhichnormallyhavetheoperatingvoltagebetweenthem

Note1toentry:Thesurfaceofanynon-insulatingjointingmaterialisnotconsideredasformingpartofthecreepagedistance.

[SOURCE:IEC60050-471:2007,471-01-04,modified–removalofNote2toentry]

3.10

arcingdistance

shortestdistanceintheairexternaltotheinsulatorbetweenthemetallicpartswhichnormallyhavetheoperatingvoltagebetweenthem

Note1toentry:Theterm"dryarcingdistance"isalsoused.

[SOURCE:IEC60050-471:2007,471-01-01,modified–additionofNote1toentry]

3.11

tracking

processwhichformsirreversibledegradationbyformationofconductivepaths(tracks)startinganddevelopingonthesurfaceofaninsulatingmaterial

Note1toentry:Thesepathsareconductiveevenunderdryconditions.

[SOURCE:IEC62217:2012,3.15]

3.12

erosion

irreversible