Equipment & SystemsQuestion 285 of 521
What is the rated secondary current of a 75 kVA, three-phase transformer with a 208 V secondary?
a.208 A
b.360 A
c.180 A
d.125 A
Explanation
Three-phase current: I = 75,000 / (1.732 x 208) = 75,000 / 360 = about 208 A. Dividing by 208 V alone (360 A) omits sqrt(3), and the other values use wrong kVA or voltage.
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