Branch Circuits & Feeders第 29 / 120 题
What is the line current of a balanced 45 kVA, three-phase, 208-volt load?
a.216 amperes
b.125 amperes
c.72 amperes
d.144 amperes
解析
For a three-phase load, I = VA / (1.732 x E) = 45,000 / (1.732 x 208) = 45,000 / 360.3, or about 125 A. The 216-ampere answer divides by the voltage alone as if the load were single-phase, 72 amperes divides by three times the voltage, and 144 amperes does not follow from the formula.
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