Motors & Equipment第 91 / 120 题
For that same two-motor feeder, if the largest branch-circuit protective device is 90 amperes, what is the maximum feeder overcurrent device rating?
a.90 amperes
b.104 amperes
c.110 amperes
d.100 amperes
解析
The feeder device may not exceed the largest branch-circuit short-circuit and ground-fault protective device plus the sum of the full-load currents of the other motors: 90 + 14 = 104 A. Since 104 is not a standard rating and this is a maximum rather than a minimum, the next lower standard size of 100 amperes must be selected. Choosing 110 amperes would exceed the calculated ceiling.
法律依据: 2023 NEC §430.62(A)免费刷完整 120 道题库 — 无需注册。
同考点相关题目
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