CalculationsQuestion 17 of 110
A feeder supplies three motors with full-load currents of 34 A, 28 A, and 22 A. What minimum conductor ampacity is required for the feeder?
a.92.5 A
b.105 A
c.84 A
d.110 A
Explanation
Feeder ampacity = 125% of the largest motor FLC plus the sum of the others: (34 x 1.25) + 28 + 22 = 42.5 + 50 = 92.5 A.
Law Reference: 2023 NEC 430.24Practice all 110 questions free — no signup required.
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