2

1.0ScopeThismethoddescribesatechniqueforevaluat-

ingamaterialtoresisttrackingwhensubjectedtoalowcur-

rentarcjustabovethesurfaceofthematerial.Itcanbeused

onmaterialsofvariousthicknessbystackingmaterials.This

procedureisbasedontechniquesdescribedinASTMD495.

2.0ApplicableDocuments

ASTMD495StandardTestMethodforHighVoltage,Low-

Current,DryArcResistanceofSolidElectrical

Insulation

Manufacturer’sInstructionManual

3.0TestSpecimens

3.1NumberThreespecimensshallbeusedunlessother-

wisespecified.

3.2FormEachspecimenshallbe3.0in.x2.0in.Material

under0.06in.inthicknessshallbebuiltuptoprovideaspeci-

menatleast0.06in.butnotexceeding0.125in.Forverythin

laminatesa1/16in.laminateofthesametypemaybeused

undertheactualspecimensubjectedtothearc,permittinga

reductionofthematerialrequiredwithoutsignificantlyaffecting

theresults.

3.3LocationSpecimensmaybecutfromanylocationina

sheet(exceptfromtheouter1in.offullsizesheets).

3.4FoilCladMaterialsAllfoilcladmaterialsshallhavethe

foilremovedbyetchingandshallbethoroughlycleanedprior

toconditioningortesting.

4.0Apparatus/Materials

4.1Arctester(BeckmanART-1

1

orequivalent,seeASTM

D495).

4.2Tungstenelectrodes(Beckman

2

orequivalent,see

ASTMD495).

4.3Constanttemperaturewaterbathcapableof50°C±

2°C,filledwithdistilledwater.

4.4Beakerorpanfilledwithambienttemperaturedistilled

water.

4.5Racksforsupportingspecimensinthewaterbathwith

allsurfacesexposed.

4.6Shear,saworpapercutterforcuttingspecimen.

4.7Alcoholorothersolventforcleaningelectrode.

4.8Crocuscloth.

4.9Gageblocksforcheckingelectrodespacing0.248in.

and0.252in.

4.10Lintfreepapertowels.

4.11Variac

3

autotransformertypeW1OMTorequivalent.

5.0Procedure

5.1PreconditioningUnlessotherwisespecifiedthespeci-

mensshallbeconditionedfor48hours(±2hours-0hours)in

distilledwatermaintainedat50°C±2°C.Followingthisstep

thespecimensshallbeimmersedinambienttemperaturedis-

tilledwaterfor30minutesminimum,4hoursmaximum,to

allowthemtoreachtemperatureequilibriumwithoutlossof

moisture.

5.2TestConditionsThetestshallberunatambienttem-

perature23°C±5°Candambienthumidity.

5.3Equipmentsetup

5.3.1Theelectrodeassemblyshallbecleanedthoroughly

usingalcoholorothersuitablesolventand,ifrequired,with

crocuscloth.Theelectrodegapshallbeadjustedifnecessary

toprovideagapof0.250in.±0.002in.whentheelectrodes

1.ART-1orART-2manufacturedbyBeckmanInstrumentsCedarGroveEssexCountyNewJersey,U.S.A.

2.ElectrodesmanufacturedbyBeckmanInstruments

3.VariacavailablefromGeneralRadio

TheInstituteforInterconnectingandPackagingElectronicCircuits

2215SandersRoad?Northbrook,IL60062

IPC-TM-650

TESTMETHODSMANUAL

Number

2.5.1

Subject

ArcResistanceofPrintedWiringMaterial

Date

5/86

Revision

B

OriginatingTaskGroup

N/A

MaterialinthisTestMethodsManualwasvoluntarilyestablishedbyTechnicalCommitteesoftheIPC.Thismaterialisadvisoryonly

anditsuseoradaptationisentirelyvoluntary.IPCdisclaimsallliabilityofanykindastotheuse,application,oradaptationofthis

material.Usersarealsowhollyresponsibleforprotectingthemselvesagainstallclaimsorliabilitiesforpatentinfringement.

EquipmentreferencedisfortheconvenienceoftheuseranddoesnotimplyendorsementbytheIPC.

Page1of2

restonthetestspecimen.

5.3.2Thearctestershouldbesetupforoperationinthe

automaticmode.

5.3.3SettheVariactothevoltagewhichproduces12,500

voltsbasedonthelastcalibrationoftheInstrument(generally

105Vto115V).

5.3.4Resetthetimeronthetesterto‘‘0’’secondsif

required.

5.4TestProcedure

5.4.1Removeapreconditionedspecimenfromtheambient

temperaturedistilledwaterandwipedrywithalintfreepaper

towel.

5,4.2Placeaspecimen(individualorbuiltup)intheelec-

trodefixture.

5.4.3Operatethetesterinaccordancewiththemanufactur-

er’sinstructionssuchthatanarcisgeneratedandautomati-

callyswitchedasindicatedbelow.

Time(sec)On/OffTimeAmperage

0-600.25sec/1.75sec10milliamps

60-1200.25sec/0.75sec10milliamps

120-1800.25sec/0.25sec10milliamps

180continuous10milliamps

5.4.4Observethearccarefullyand,atthepointwhichthe

arcdisappearsandtrackingoccurs,stopthetimerandrecord

thetimeforthespecimentothenearestsecond.

5.4.5Removethespecimen,removeandcleantheelec-

trodesthoroughlyusingasolventandifnecessarythecrocus

cloth.

5.4.6Replacetheelectrodeandchecktheelectrodegap.

5.4.7Resetthetimerandproceedasin5.4.1through5.4.6.

5.5Calculation

5.5.1Averagethevaluesofthespecimenstestedfromthe

samesampleandroundtothenearestsecond.

5.6Report

5.6.1Reporttheaveragevalueofthearcresistanceinsec-

onds.

5.6.2Reporttheambienttemperatureandrelativehumidity

atthetimeofthetest.

5.6.3Reporthowthespecimenwasprepared,e.g.indi-

vidual,#ofpliesbuiltup,orwithaspacer.

5.6.4Reportthepreconditioningprocedure.

5.6.5Reportanyanomaliesinthetestorvariationsfrom

proceduresortolerancesspecified.

6.0Note

6.1Theresultsofarctestsmaybesignificantlyaffectedby

contaminationoftheelectrodes.Anyirregularityofthearcin

theearlyportionofthetestmaybeanindicationofcontami-

nation.Ifthisoccurs,thetestshouldbestopped,theelec-

trodescleanedandafreshspecimenshouldbetested(orthe

testmayberuninadifferentareaofthesamespecimen).

6.2Whilevaluesforreinforcedmaterialmayvarywiththe

graindirectionofreinforcement,theeffectisgenerallyinsignifi-

cantwithglassreinforcedproduct.Atleastonespecimenin

bothmachineandtransversedirectionisrecommendedto

verifythis.

IPC-TM-650

Number

2.5.1

Subject

ArcResistanceofPrintedWiringMaterial

Date

5/86

Revision

B

Page2of2