Branch Circuits & FeedersQuestion 1 of 120
A 208-volt, single-phase branch circuit supplies a continuous load of 24 amperes. What is the minimum standard overcurrent device rating permitted?
a.30 amperes
b.25 amperes
c.24 amperes
d.40 amperes
Explanation
An overcurrent device supplying a continuous load must be rated at not less than 125 percent of that load: 24 A x 1.25 = 30 A, which is a standard rating in 240.6(A). The 24 A and 25 A choices ignore or under-apply the 125 percent factor, and 40 A jumps past the next standard size above the calculated value.
Law Reference: 2023 NEC §210.20(A)Practice all 120 questions free — no signup required.
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