Dịch vụ & Phân phốiCâu 100 / 521
Where the grounding electrode conductor connects to a made rod, pipe, or plate electrode, that portion of the conductor is not required to be larger than:
a.4 AWG copper
b.6 AWG copper
c.2 AWG copper
d.1/0 AWG copper
Giải thích
Per 250.66(A), the portion of the grounding electrode conductor that is the sole connection to a rod, pipe, or plate electrode need not be larger than 6 AWG copper. The 4 AWG limit is for concrete-encased electrodes, and larger sizes exceed the code requirement for a ground rod.
Trích dẫn luật: 2023 NEC §250.66Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- The minimum depth of working space in front of a 208Y/120 V panelboard (0-150 V to ground, Condition 1: exposed live parts on one side, no live or grounded parts on the other) is:
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