Services & Distribution第 52 / 110 题
A 200-A busbar has a 200-A main breaker at one end. Using the 120% rule, what is the maximum back-fed inverter (PV) overcurrent device at the opposite end?
a.20 A
b.60 A
c.30 A
d.40 A
解析
120% of the 200-A busbar = 240 A. Subtract the 200-A main: 240 - 200 = 40 A maximum for the back-fed supply breaker.
法律依据: 2023 NEC 705.12(B)免费刷完整 110 道题库 — 无需注册。
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