Answer / sridhar nayak

by the help of tester the insulation of the cable canbe
measured. the simple technique is just raotate the handle
of the megger and place the test prod one on conductor and
other on the insulation it should not show less then 2mohms.

Answer / savarkarshriram

If cable is rated for 1.1KV the megger test( Insulation
resistance test) is done with use of 500V or 1000V.
The test probes are connected across each phase , neutral
and ground terminal so that it covers all combinations.

If it is HT cable then 2000V IR tester is used. with the
same method as explained above.
Thumb rule for minimum value is 1M ohm per KV of rated
volatge of equipment

( Mind you megger is name of company and not name of test
so engineers should use term insulation resistance rather
than megger)

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