Services & Distribution第 53 / 110 题
A single made electrode (ground rod) must be supplemented unless its resistance to earth does not exceed what value?
a.25 ohms
b.5 ohms
c.10 ohms
d.1 ohm
解析
A single rod, pipe, or plate electrode must be supplemented by a second electrode unless it has a resistance to earth of 25 ohms or less.
法律依据: 2023 NEC 250.53(A)免费刷完整 110 道题库 — 无需注册。
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