關(guān)于爬電距離和空氣間隙的標(biāo)準(zhǔn)第1頁(yè)，共36頁(yè)。（優(yōu)選）關(guān)于爬電距離和空氣間隙的標(biāo)準(zhǔn).第2頁(yè)，共36頁(yè)。Minimumclearance(Table2)RatedimpulsevoltageVMinimumclearancemm3300.55000.58000.515000.525001.540003.060005.580008.0100011.0第3頁(yè)，共36頁(yè)。HowtofindtheminimumclearanceHouseholdapplianceareinovervoltagecategoryIISelecttheratedvoltageUsingthetable1tofindouttheratedimpulsevoltageAccordingtotable2,theminimumclearancecouldbefoundbyratedimpulsevoltageTheclearancesoffourinsulationtypes:BasicinsulationSupplementaryinsulationReinforcedinsulationFunctionalinsulation第4頁(yè)，共36頁(yè)。TheclearanceofbasicinsulationExample1 :WaterkettleRating :220–240V50Hz2500–3000WRatedvoltageVRatedimpulsevoltage(V)OvervoltagecategoryIIIIII<=50330500800>150and<=15080015002500>150and<=300150025004000220–240VUsingcategoryIITheratedimpulsevoltagewas2500V第5頁(yè)，共36頁(yè)。RatedimpulsevoltageVMinimumclearancemm3300.55000.58000.515000.525001.540003.060005.580008.0100011.0Theminimumclearancesofbasicinsulationwas1.5mm第6頁(yè)，共36頁(yè)。Specialcomponentsforbasicinsulation

Theterminalsoftubularsheathedheatingelementscounted1mm,ifthemicroenvironmentispollutiondegree1.>1mmTubularsheathedheatingelementPollutiondegree1第7頁(yè)，共36頁(yè)。TheminimumclearanceissameasthebasicinsulationThedistancebetweenenclosureandinternalwire第8頁(yè)，共36頁(yè)。Thereinforcedinsulationusingthenextstepforratedimpulsevoltage.Betweenterminalandplasticenclosure第9頁(yè)，共36頁(yè)。BetweenterminalsThefunctionalinsulationisbetweenlivepartsofdifferentpotential第10頁(yè)，共36頁(yè)。PTCHeatingelementHairstraighterPTCheaterHairstraighterassembly第11頁(yè)，共36頁(yè)。DifferenttypesofPTCHeatingelements第12頁(yè)，共36頁(yè)。InternalconstructionofPTCheatingelementTheclearancebetweensurfacesofPTCheatingelementsmaybereducedto1mmTheclearance>=1mmKaptonfilmPTCheatingplateElectrodeplate第13頁(yè)，共36頁(yè)。29.2creepagedistancesStep1(Tofindoutthepollutiondegree)Pollutiondegree2appliesunlessPrecautionshavebeentakentoprotecttheinsulation,inwhichcasepollution1appliesTheinsulationissubjectedtoconductivepollution,inwhichcasepollutiondegree3appliesNote:Thepollutiondegreeshouldneedrefertopart2.第14頁(yè)，共36頁(yè)。StandardPollutiondegree60335–2–3II60335–2–9III60335–2–14III60335–2–15III60335–2–23II60335–2–80IIIPollutiondegreeclassification第15頁(yè)，共36頁(yè)。Trackingindex(CTI)valuesMaterialgroupI:600<=CTIMaterialgroupII:400<=CTIMaterialgroupIIIa:175<=CTI<400MaterialgroupIIIb:100<=CTI<175Step2(Tofindoutthematerialgroup)

Trackingindextester第16頁(yè)，共36頁(yè)。Trackingindex(CTI)values第17頁(yè)，共36頁(yè)。MinimumcreepagedistancesforbasicinsulationWorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b<=500.20.60.91.21.51.71.9a>50and<=1250.30.81.11.51.92.12.4>125and<=2501.61.31.82.53.23.64.0>250and<=4001.02.02.84.05.05.66.3>400and<=5001.32.53.65.06.37.18.0>500and<=8001.83.24.56.38.09.010.0第18頁(yè)，共36頁(yè)。ThecreepageofbasicinsulationExample1:WaterkettleRating:220–240V50Hz2500–3000WPollutiondegree3(refertostandard60335–2–15)Themicroenvironmentispollutiondegree3iftheinsulationcanbe pollutedbycondensationfromsteamproducedduringnormaluseof appliance.AssumethematerialgroupisIII(thetightengrade)Workingvoltageisbetween>125and<=250第19頁(yè)，共36頁(yè)。ThecreepageofbasicinsulationWorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b<=500.20.60.91.21.51.71.9a>50and<=1250.30.81.11.51.92.12.4>125and<=2501.61.31.82.53.23.64.0>250and<=4001.02.02.84.05.05.66.3>400and<=5001.32.53.65.06.37.18.0>500and<=8001.83.24.56.38.09.010.0第20頁(yè)，共36頁(yè)。WorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b<=500.20.60.81.11.41.61.8a>50and<=1250.30.71.01.41.82.02.2>125and<=2500.41.01.42.02.52.83.2>250and<=4000.81.62.23.24.04.55.0>400and<=5001.02.02.84.05.05.66.3>500and<=8001.83.24.56.38.09.010.0Minimumcreepagedistancesforfunctionalinsulation第21頁(yè)，共36頁(yè)。InsulationtypeDistanceBasicinsulation4Supplementaryinsulation4Reinforcedinsulation8Functionalinsulation3.2SummaryofMinimumcreepagedistances

第22頁(yè)，共36頁(yè)。1.5mmCreepagedistanceofwindingneednotbegreaterthantheassociatedclearancespecifiedintable16第23頁(yè)，共36頁(yè)。

Theinternalwireofmicro-switchwasnotsecurelyfixedthatitwaspossibletobetouchedbytestfingerwith2Nforce.Thecreepagedistanceweremeasuredas0mmInternalwireshallbeaccess第24頁(yè)，共36頁(yè)。

Thecreepagedistancesofreinforcedinsulationshallnotlessthan8mm.Asresult,thecreepagedistancewasmeasured7.5mmbetweenleadsofneonlampandthelampcoverjoint.

LeadsofneonlampLensEnclosureLeonlampleads2mm3mm2.5mThecreepagedistances=2.5+2+3 =7.5mm第25頁(yè)，共36頁(yè)。

CreepagedistancebetweenMeasuredresultsLimitationSwitchterminals1.5mm2mm1.5mm第26頁(yè)，共36頁(yè)。DistancebetweenMeasuredresultsLimitationPCBBetweenPointAandBClearanceCreepageClearanceCreepage2.07mm2.75mm1.5mm2.0mm第27頁(yè)，共36頁(yè)。PCBTrackABBABA第28頁(yè)，共36頁(yè)。Creepagedistancesmaybereducediftheappliancecomplieswithclause19withthefunctionalinsulationshort-circuited.Forexample:ElectroniccomponentElectroniccomponentThetransistorleads<limitationofcreepagedistance第29頁(yè)，共36頁(yè)。L