Why is it that polarization index type test is required for
MV and HV motors and not for LV motors?
Answer Posted / cr
As we r letting high current pass through the winding using ht megger,there by improving I.R because the heat produced and the ir ratio for 10 to 1 minute should be around 2.otherwise the insulation can be said to be contaminated with foreign meterial , this check is priority for ht motors
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