Dielectric Absorption Ratio

DAR measurement is a diagnostic test similar to the Polarization Index (PI), but DAR takes the ratio of the Insulation Resistance usually measured at 30 sec and 1 min (other time settings are possible) instead of 1 min and 10 min typically of the PI.
DAR measurements are useful for instance when the PI is 2 or less even for new objects under test. In such cases, a min DAR value of 1.25 is required.

Dielectric Absorption Ratio = TIME 2
Insulation resistance value 30 sec. or 1 min.
after starting measurement TIME 1
Insulation resistance value 15 or 30 sec.
after starting measurement