Branch Circuits & Feeders第 8 / 120 题
A feeder supplies 30 amperes of continuous load plus 50 amperes of noncontinuous load. What is the minimum standard overcurrent device rating?
a.100 amperes
b.80 amperes
c.90 amperes
d.110 amperes
解析
The device must be sized for the noncontinuous load plus 125 percent of the continuous load: 50 + (30 x 1.25) = 87.5 A, and the next standard size in 240.6(A) is 90 A. The 80 A answer simply adds the loads without the 125 percent factor, and 100 A or 110 A skip past the next standard rating.
法律依据: 2023 NEC §215.3免费刷完整 120 道题库 — 无需注册。
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