Services, Grounding & Bonding第 46 / 120 题
Where two rod electrodes are installed to make up the grounding electrode system, what is the minimum spacing between them?
a.3 feet
b.6 feet
c.8 feet
d.10 feet
解析
Rods that supplement one another must be separated by at least 6 feet so their earth shells do not overlap and defeat the purpose of the second rod. The 8-foot figure is the minimum rod length rather than spacing, and 3 or 10 feet are not the code minimum.
法律依据: 2023 NEC §250.53(A)(3)免费刷完整 120 道题库 — 无需注册。
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