Thiết bị & Hệ thốngCâu 265 / 521
A 45 kVA, three-phase transformer has a 208 V secondary. What is the rated secondary current?
a.125 A
b.108 A
c.216 A
d.150 A
Giải thích
For three-phase, I = VA / (1.732 x V) = 45,000 / (1.732 x 208) = 45,000 / 360 = about 125 A. Dividing by 208 alone (216 A) ignores the sqrt(3) factor, and the other values use wrong voltages.
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