Equipment & SystemsQuestion 264 of 521
What is the rated primary current of a 25 kVA, single-phase transformer with a 240 V primary?
a.60 A
b.83 A
c.96 A
d.104 A
Explanation
For a single-phase transformer, I = VA / V = 25,000 / 240 = 104 A. Using 208 V would give 120 A, 300 V gives 83 A, and 416 V gives 60 A; only the correct 240 V yields about 104 A.
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