Calculations第 18 / 110 题
What is the full-load primary current of a 75-kVA, 480-V, three-phase transformer?
a.156 A
b.90 A
c.104 A
d.72 A
解析
Three-phase current = VA / (1.732 x V): 75,000 / (1.732 x 480) = 90.2 A, about 90 A.
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