Calculations第 23 / 110 题
A 208-V three-phase feeder carries 40 A over 150 ft using #6 Cu (CM = 26,240, K = 12.9). What is the approximate voltage drop?
a.3.0 V
b.7.2 V
c.5.1 V
d.9.0 V
解析
Three-phase VD = (1.732 x K x I x L) / CM = (1.732 x 12.9 x 40 x 150) / 26,240 = 134,050 / 26,240 = 5.11 V.
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