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Dielectric Absorption Ratio (DAR)
The dielectric absorption test calculates the ratio of the resistance measurement after one minute to
the resistance measurement after 30 seconds: Results are determined by the type, age and
condition of the insulation material tested. Established standards and test procedures should be
used to establish pass/fail criteria for each application.
Dielectric Absorption Ratio = Resistance after 1 minute / Resistance after 30 seconds
1. Connect the Black Earth test lead to the Earth connector and the Red test lead to the LINE and
COM connectors.
2. Connect the test leads to the device under test.
3. Set the Function Selector switch to the desired insulation test voltage.
4. Use the PI/DAR button to select the Dielectric Absorption Ratio function (DAR) for TIME1.
5. Press and hold the PRESS TO TEST button and turn it clockwise to the LOCK position. The
beeper will sound during the test.
6. When the test has completed, the LCD will display PASS if the Dielectric Absorption Ratio is
greater than 1. FAIL will be displayed if the Dielectric Absorption Ratio is below 1.
7. Keep the test leads connected to the device under test and release the PRESS TO TEST
button. The circuit will discharge through the meter. While the circuit is discharging, the
icon will flash.
8. Press the STOP button to clear the results
Insulation Resistance Measurement Considerations
The Resistance of an insulator is determined by applying a test voltage to the insulator and then
measuring the subsequent current flow.
Notes:
The insulation resistance of a device may not be stable therefore the readings supplied by
the meter may vary.
An audible beep will be heard while a test is in progress, this is normal.
Measurements taken on a capacitive load may take some time to complete.
Insulation Resistance tests output a positive (+) voltage from the Earth terminal and a
negative (-) voltage from the Line terminal.
