The phase windings of an alternator are connected in wye. The alternator produces a line voltage of 440V and supplies power to two resistive loads. One load contains resistors with a value of 4 ohm each, connected in wye. The second load contains resistors with a value of 6 ohm each, connected in delta. Both loads are connected directly to the output of the alternator. The line voltage for both loads 1 and 2 will be the same, ____V.
A) 73.33
B) 219.09
C) 220
D) 440

Question

Quizplus · Accepted Answer

When connected in wye, the line voltage of the alternator is equal to the phase voltage. Therefore, the phase voltage of the alternator is 440V / √3 = 254.03V.

For load 1 (connected in wye), the line voltage is equal to the phase voltage. Therefore, the line voltage for load 1 is also 254.03V.

For load 2 (connected in delta), the line voltage is √3 times the phase voltage. Therefore, the line voltage for load 2 is 254.03V x √3 = 440V.

Since both loads are connected directly to the output of the alternator, they share the same line voltage. Therefore, the line voltage for both loads is 254.03V, or approximately 220V. The closest answer choice is C, 220V.

The Phase Windings of an Alternator Are Connected in Wye