Branch Circuits & Feeders第 9 / 120 题
Which of the following is NOT a standard ampere rating for fuses and inverse-time circuit breakers?
a.110 amperes
b.45 amperes
c.70 amperes
d.55 amperes
解析
The standard ratings listed in 240.6(A) include 45, 50, 60, 70, 80, 90, 100 and 110 amperes, but 55 amperes is not among them. Knowing this list matters because calculated loads are routinely rounded up to the next standard rating, and selecting a size that does not exist is a common exam trap.
法律依据: 2023 NEC §240.6(A)免费刷完整 120 道题库 — 无需注册。
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