Motors & Equipment第 98 / 120 题
For that same 20-ampere rated-load compressor supplied alone, what minimum conductor ampacity is required?
a.35 amperes
b.20 amperes
c.25 amperes
d.30 amperes
解析
Branch-circuit conductors for a single motor-compressor must have an ampacity of at least 125 percent of the rated-load current or branch-circuit selection current, whichever is greater: 20 x 1.25 = 25 A, which calls for 10 AWG copper. The 35-ampere figure is the 175 percent protective device calculation, and 20 amperes omits the required multiplier entirely.
法律依据: 2023 NEC §440.32免费刷完整 120 道题库 — 无需注册。
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