ASTM D924-2008 电绝缘液体的损耗因数(或功率因数)和电容率(介电常数)的标准试验方法

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【英文标准名称】:StandardTestMethodforDissipationFactor(orPowerFactor)andRelativePermittivity(DielectricConstant)ofElectricalInsulatingLiquids
【原文标准名称】:电绝缘液体的损耗因数(或功率因数)和电容率(介电常数)的标准试验方法
【标准号】:ASTMD924-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:D27.05
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:dielectricconstant;dissipationfactor;powerfactor;relativehumidity;Dissipationfactor;Electricalinsulatingliquids;Permittivity(dielectricconstant)--electricalinsulatingmaterials
【摘要】:DissipationFactor(orPowerFactor)8212;Thisisameasureofthedielectriclossesinanelectricalinsulatingliquidwhenusedinanalternatingelectricfieldandoftheenergydissipatedasheat.Alowdissipationfactororpowerfactorindicateslowacdielectriclosses.Dissipationfactororpowerfactormaybeusefulasameansofqualitycontrol,andasanindicationofchangesinqualityresultingfromcontaminationanddeteriorationinserviceorasaresultofhandling.Thelosscharacteristiciscommonlymeasuredintermsofdissipationfactor(tangentofthelossangle)orofpowerfactor(sineofthelossangle)andmaybeexpressedasadecimalvalueorasapercentage.Fordecimalvaluesupto0.05,dissipationfactorandpowerfactorvaluesareequaltoeachotherwithinaboutonepartinonethousand.Ingeneral,sincethedissipationfactororpowerfactorofinsulatingoilsingoodconditionhavedecimalvaluesbelow0.005,thetwomeasurements(terms)maybeconsideredinterchangeable.Theexactrelationshipbetweendissipationfactor(D)andpowerfactor(PF)isgivenbythefollowingequations:ThereportedvalueofDorPFmaybeexpressedasadecimalvalueorasapercentage.Forexample:RelativePermittivity(DielectricConstant)8212;Insulatingliquidsareusedingeneraleithertoinsulatecomponentsofanelectricalnetworkfromeachotherandfromground,aloneorincombinationwithsolidinsulatingmaterials,ortofunctionasthedielectricofacapacitor.Forthefirstuse,alowvalueofrelativepermittivityisoftendesirableinordertohavethecapacitancebeassmallaspossible,consistentwithacceptablechemicalandheattransferproperties.However,anintermediatevalueofrelativepermittivitymaysometimesbeadvantageousinachievingabettervoltagedistributionofa-celectricfieldsbetweentheliquidandsolidinsulatingmaterialswithwhichtheliquidmaybeinseries.Whenusedasthedielectricinacapacitor,itisdesirabletohaveahighervalueofrelativepermittivitysothephysicalsizeofthecapacitormaybeassmallaspossible.TheoryrelatingtodielectricmeasurementtechniquesandtosourcesofdielectriclossisgiveninTestMethodsD150.1.1Thistestmethoddescribestestingofnewelectricalinsulatingliquidsaswellasliquidsinserviceorsubsequenttoserviceincables,transformers,oilcircuitbreakers,andotherelectricalapparatus.1.2Thistestmethodprovidesaprocedureformakingrefereetestsatacommercialfrequencyofbetween45and65Hz.1.3Whereitisdesiredtomakeroutinedeterminationsrequiringlessaccuracy,certainmodificationstothistestmethodarepermittedasdescribedinSections16to24.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesandtodeterminetheapplicabilityofregulatorylimitationspriortouse.Specificwarningsaregivenin11.3.3.1.5MercuryhasbeendesignatedbytheEPAandmanystateagenciesasahazardousmaterialthatcancausenervoussystem,kidneyandliverdamage.Mercury,oritsvapor,maybehazardoustohealthandcorrosivetomaterials.Cautionshouldbetakenwhenhandlingmercuryandmercury......
【中国标准分类号】:K15
【国际标准分类号】:29_040_10
【页数】:7P.;A4
【正文语种】:英语