INSULATIONRESISTANCETESTING(绝缘阻抗测试仪)INSULATIONRESISTANCETESTING(绝缘阻抗测试仪)ModelTestVoltage(VDC)RangePowerSourceDisplay22232E500,10000-1000MBatteriesAnalog/Digital8000E100,250,500,10000-2000MHandCrankedAnalog8003E100,250,500,10000-20,000MHandCrankedAnalog8012E500,1000,2500,50000-100,000MRECHARGEABLEAnalogAnyitemthatcarrieselectricalcurrentiscoveredwithsometypeofinsulation.Theinsulationrestrictstheflowofcurrentbetweendifferentconductorsandbetweenconductorsandground.Theinsulationsystemissubjecttostress,andcontaminationovertime.Iftheinsulationsystemfailsitcanbeverycostly.AnIRTestmeasurestheelectricalinsulationresistanceofthesystem.Thetestmaybedoneasaquickcheckafteranitemismanufactured,installedorrepaired.Itisalsoausefultesttoperformwhendoingpreventativemaintenanceonanitemovertime.Changesintheinsulationmeasurementcanhelptopredictanincipientfailureofanitemsuchasamotor,cableorcomponent.TheIRTestisperformedwithaDCpotential.ThisDCpotentialisimpressedacrosstheinsulationsystembetweencircuitsand/orgroundandtheresultingcurrentsaremeasured.ThemeterisusuallyscaledinMegohmswhichistheratiooftheDCvoltageversusthemeasuredcurrent(R=E/1).ThetwomostcommonIRTest'sarePolarizationIndexandDielectricAbsorption.)