Branch Circuits & FeedersQuestion 9 of 120
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
Explanation
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.
Law Reference: 2023 NEC §240.6(A)Practice all 120 questions free — no signup required.
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