Dịch vụ & Phân phốiCâu 8 / 521
A ground ring is used as a grounding electrode. What is the minimum size and length required?
a.6 AWG copper, at least 10 ft
b.4 AWG copper, at least 20 ft
c.2 AWG copper, at least 10 ft
d.2 AWG copper, at least 20 ft
Giải thích
Section 250.52(A)(4) requires a ground ring of at least 2 AWG bare copper encircling the building for a length of not less than 20 ft. Smaller conductors or shorter lengths do not qualify as a ground ring electrode.
Trích dẫn luật: 2023 NEC §250.52(A)(4)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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