In a three phase transformer, if the primary side is connected in star and secondary side is connected in delta, what is the angle difference between phase voltage in the two cases. (A) delta side lags by -30°. (B) star side lags by -30°. (C) delta side leads by 30°. (D) star side leads by -30°.

In a three phase transformer, if the primary side is connected in star and secondary
side is connected in delta, what is the angle difference between phase voltage in the
two cases.
 (A) delta side lags by -30°. (B) star side lags by -30°.
 (C) delta side leads by 30°. (D) star side leads by -30°.
by

1 Answer

Answer :

Ans: C
 This is vector group and has +30° displacement. Therefore, delta side leads by +30°.
by

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