what is the meaning of pi value?



what is the meaning of pi value?..

Answer / raveendra nath

PI value is the ratio of insulation resistance at 10
minutes to the 1 minute value...

PI = IR(10 min) / IR (1 min)

For good insulation, PI >= 2
PI more than 1.5 is acceptable...
PI less than <1 indicates Bad insulation

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