In a three phase transformer, if the primary side is connected in star and secondary side is connected in...

In a three phase transformer, if the primary side is connected in star and secondary side is connected in delta, the angle difference between phase voltage in the two cases will be: (A) delta side will lag by -30° (B) star side will lag by -30° (C) delta side will lead by 30° (D) star side will lead by -30°
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In a three phase transformer, if the primary side is connected in star and secondary side is connected in delta, the angle difference between phase voltage in the two cases will be: delta side will lead by 30° 

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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°.

Description : 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°.

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

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Description : A load with an impedance of 440 ohms is connected across the secondary of the transformer illustrated. If the input voltage is 110 VAC and the step-up ratio is 10 to 1, what will be the primary current? EL-0055 A. 2.5 amps B. 25 amps C. 250 amps D. current cannot be determined with information given

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Last Answer : A. there are 20 turns on primary one turn on secondary

28.In a two winding transformer, the emf /turn in secondary winding is always......the induced emf power turn in primary A. equal to k times B. equal to 1/k times C. equal D. greater than

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The primary winding of a 220/6 V, 50 Hz transformer is energised from 110 V, 60 Hz supply. The secondary

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