Answer / j.kesavan

Dar means dielectric absorption ratio test in HT
machines.HT megger reading 1minite/30second reading is Dar
test.

Answer / sam

DARThe is The ratio of a 60 s reading to a 30 s reading
this ratio of time-resistance readings can be used to
indicatethe condition of the insulation system.
DAR = Recsistance 60 sec / Resistance 30 sec
Goog Insulation DAR more than 1.25

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