Services & DistributionQuestion 46 of 521
What is the full-load primary current of a 75 kVA, 3-phase, 480 V transformer?
a.156 A
b.125 A
c.90 A
d.72 A
Explanation
I = 75,000 / (1.732 x 480) = 90.2 A, so about 90 A. The other choices omit the sqrt-3 factor or use the wrong voltage.
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