Answer / shyam

polarity can be checked with ac also. but it needs phase
angle measurement. with a dc we can observe +ve/-ve
deflection on galvanometer(u can use ma dc analog meter,
dont use digital meter which will have more response time).
apply dc at low voltage for msec time(flick only) otherwise
ct may saturate. please read CPC100 manual of omicron for
further knowledge.

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