what is PI value and its significance for insulation
testing?

Answer Posted / mohammed sarfraz

POLARIZATION INDEX is ability of the insulation to absorb
the voltage over a period af time, this give an indication
of the overall insulation quality of individual pieces of
insulation in the transformer. this test is usually
performed as ratio of insulation resistance for 10 minutes
to ir value of 1 minutes.

the value should be less then 2.5.

Is This Answer Correct ?    35 Yes 27 No



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