Services, Grounding & BondingCâu 46 / 120
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
Giải thích
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.
Trích dẫn luật: 2023 NEC §250.53(A)(3)Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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