Advanced Wiring第 77 / 110 题
A motor feeder supplies motors whose largest branch device is 90 A, plus other motors with 50 A total full-load current. What is the maximum feeder short-circuit/ground-fault device (not to exceed the sum, next standard down)?
a.125 A
b.150 A
c.175 A
d.110 A
解析
The feeder device may not exceed the largest branch-circuit device (90 A) plus the other FLCs (50 A) = 140 A; the largest standard rating not exceeding 140 A is 125 A.
法律依据: 2023 NEC 430.62免费刷完整 110 道题库 — 无需注册。
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