Services, Grounding & BondingCâu 45 / 120
What is the minimum length of a rod-type grounding electrode?
a.10 feet
b.6 feet
c.8 feet
d.5 feet
Giải thích
Rod and pipe electrodes must be at least 8 feet long and must have at least 8 feet in contact with the soil once installed. The 10-foot value is associated with the minimum earth contact required of a metal underground water pipe electrode, and 5 or 6 feet fall short of the rod requirement.
Trích dẫn luật: 2023 NEC §250.52(A)(5)Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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