EN60335关于爬电距离和空气间隙的标准

RatedvoltageVRatedimpulsevoltageVOvervoltagecategoryIIIIII=5033050080050and=15080015002500150and=300150025004000Clause29Clearances,Creepagedistancesandsolidinsulation爬电距离、电气间隙和绝缘穿通距离(Table1)Minimumclearance(Table2)RatedimpulsevoltageVMinimumclearancemm3300.55000.58000.515000.525001.540003.060005.580008.01000011.0HowtofindtheminimumclearanceHouseholdapplianceareinovervoltagecategoryIISelecttheratedvoltageUsingthetable1tofindouttheratedimpulsevoltageAccordingtotable2,theminimumclearancecouldbefoundbyratedimpulsevoltageTheclearancesoffourinsulationtypes:1.Basicinsulation2.Supplementaryinsulation3.Reinforcedinsulation4.FunctionalinsulationTheclearanceofbasicinsulationExample1:WaterkettleRating:220–240V50Hz2500–3000WRatedvoltageVRatedimpulsevoltage(V)OvervoltagecategoryIIIIII=50330500800150and=15080015002500150and=300150025004000220–240VUsingcategoryIITheratedimpulsevoltagewas2500V29.1.1clearancesofbasicinsulationRatedimpulsevoltageVMinimumclearancemm3300.55000.58000.515000.525001.540003.060005.580008.0100011.0Theminimumclearancesofbasicinsulationwas1.5mmSpecialcomponentsforbasicinsulationTheterminalsoftubularsheathedheatingelementscounted1mm,ifthemicroenvironmentispollutiondegree1.1mmTubularsheathedheatingelementPollutiondegree129.1.2clearanceofsupplementinsulationTheminimumclearanceissameasthebasicinsulationThedistancebetweenenclosureandinternalwire29.1.3clearanceofreinforcedinsulationThereinforcedinsulationusingthenextstepforratedimpulsevoltage.Betweenterminalandplasticenclosure29.1.4clearanceoffunctionalinsulationBetweenterminalsThefunctionalinsulationisbetweenlivepartsofdifferentpotentialPTCHeatingelementHairstraighterPTCheaterHairstraighterassemblyDifferenttypesofPTCHeatingelementsInternalconstructionofPTCheatingelementTheclearancebetweensurfacesofPTCheatingelementsmaybereducedto1mmTheclearance=1mmKaptonfilmPTCheatingplateElectrodeplate29.2creepagedistancesStep1(Tofindoutthepollutiondegree)Pollutiondegree2appliesunlessPrecautionshavebeentakentoprotecttheinsulation,inwhichcasepollution1appliesTheinsulationissubjectedtoconductivepollution,inwhichcasepollutiondegree3appliesNote:Thepollutiondegreeshouldneedrefertopart2.StandardPollutiondegree60335–2–3II60335–2–9III60335–2–14III60335–2–15III60335–2–23II60335–2–80IIIPollutiondegreeclassificationTrackingindex(CTI)valuesMaterialgroupI:600=CTIMaterialgroupII:400=CTIMaterialgroupIIIa:175=CTI400MaterialgroupIIIb:100=CTI175Step2(Tofindoutthematerialgroup)TrackingindextesterTrackingindex(CTI)valuesMinimumcreepagedistancesforbasicinsulationWorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b=500.20.60.91.21.51.71.9ª50and=1250.30.81.11.51.92.12.4125and=2501.61.31.82.53.23.64.0250and=4001.02.02.84.05.05.66.3400and=5001.32.53.65.06.37.18.0500and=8001.83.24.56.38.09.010.0ThecreepageofbasicinsulationExample1:WaterkettleRating:220–240V50Hz2500–3000WPollutiondegree3(refertostandard60335–2–15)Themicroenvironmentispollutiondegree3iftheinsulationcanbepollutedbycondensationfromsteamproducedduringnormaluseofappliance.AssumethematerialgroupisIII(thetightengrade)Workingvoltageisbetween125and=250ThecreepageofbasicinsulationWorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b=500.20.60.91.21.51.71.9ª50and=1250.30.81.11.51.92.12.4125and=2501.61.31.82.53.23.64.0250and=4001.02.02.84.05.05.66.3400and=5001.32.53.65.06.37.18.0500and=8001.83.24.56.38.09.010.0WorkingvoltageVCreepagedistancemmPollutiondegree123MaterialgroupMaterialgroupIIIIIIa/bIIIIIIa/b=500.20.60.81.11.41.61.8ª50and=1250.30.71.01.41.82.02.2125and=2500.41.01.42.02.52.83.2250and=4000.81.62.23.24.04.55.0400and=5001.02.02.84.05.05.66.3500and=8001.83.24.56.38.09.010.0MinimumcreepagedistancesforfunctionalinsulationInsulationtypeDistanceBasicinsulation4Supplementaryinsulation4Reinforcedinsulation8Functionalinsulation3.2SummaryofMinimumcreepagedistances29.2.1creepageforbasicinsulationLacqueredconductorsofwindings1.5mmCreepagedistanceofwindingneednotbegreaterthantheassociatedclearancespecifiedintable16Clause29.2.2Asperclause29.2.2,thecreepagedistanceofsupplementaryinsulationshallnotlessthanand2.5mm.Theinternalwireofmicro-switchwasnotsecurelyfixedthatitwaspossibletobetouchedbytestfingerwith2Nforce.Thecreepagedistanceweremeasuredas0mmInternalwireshallbeaccessClause29.2.3Thecreepagedistancesofreinforcedinsulationshallnotlessthan8mm.Asresult,thecreepagedistancewasmeasured7.5mmbetweenleadsofneonlampandthelampcoverjoint.LeadsofneonlampLensEnclosureLeonlampleads2mm3mm2.5mThecreepagedistances=2.5+2+3=7.5mm29.2.4creepagedistancesoffunctionalinsulationCreepagedistancebetweenMeasuredresultsLimitationSwitchterminals1.5mm2mm1.5mmClause29.2.4DistancebetweenMeasuredresultsLimitationPCBBetweenPointAandBClearanceCreepageClearanceCreepage2.07mm2.75mm1.5mm2.0mmPCBTrackABBABA29.2.4creepagedistanceforfunctioninsulationCreepagedistancesmaybereducediftheappliancecomplieswithclause19withthefunctionalinsulat