KYORITSU KEW3125A - Measurement - Continuous and PI; Principle of Insulation Resistance Measurement; Continuous Insulation Resistance Measurement; PI Measurement Explained

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Principle of Insulation Resistance Measurement
Aresistancevaluecanbeobtainedbyapplyingacertainhigh
voltagetotheresistor(insulationresistance)andmeasuringthe
flowingcurrent.
Resistancevalue=Voltage/Current
(RX=V/I)
6-3 Continuous Measurement
PressandturntheTestbuttonclockwiseandlockthebutton
to measure insulation resistances continuously. Turn the
buttoncounterclockwiseandsetittotheinitialpositionaftera
measurement.
#DANGER
●Be extremely careful not to get electric shock as a high
voltageispresentonthetipofthetestleadscontinuously.
●Keep your fingers and hands behind the protective
fingerguardduringmeasurement.
6-4 DAR/PI measurement
1. PI - Polarization index
This is to check a temporal increase of leakage currents
flowingoninsulationsandtoconfirmleakagecurrentsarent
increasedastimepasses.
PI is usually determined by the insulation resistances
measured1minand10minafterameasurementisstarted.
PI is dependent on the shape of insulations and influenced
bymoistureabsorption,therefore,acheckofPIisimportant
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