Thiết bị & Hệ thốngCâu 298 / 521
A 15 kVA, single-phase transformer has a 480 V primary. What is the rated primary current?
a.62.5 A
b.31.25 A
c.36 A
d.72 A
Giải thích
Single-phase: I = 15,000 / 480 = 31.25 A. Using 240 V would give 62.5 A, and the other values use incorrect voltages or the sqrt(3) factor that does not apply to single-phase.
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