Dịch vụ & Phân phốiCâu 99 / 521
Where the grounding electrode conductor connects to a concrete-encased electrode, that portion of the conductor is not required to be larger than:
a.6 AWG copper
b.8 AWG copper
c.2 AWG copper
d.4 AWG copper
Giải thích
Per 250.66(B), the grounding electrode conductor to a concrete-encased electrode is not required to be larger than 4 AWG copper. 6 AWG applies to a rod/pipe/plate electrode under 250.66(A), and the other sizes are not the code cap for this connection.
Trích dẫn luật: 2023 NEC §250.66Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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