Dịch vụ & Phân phốiCâu 3 / 521
The only grounding electrode is a concrete-encased electrode (Ufer). What is the largest copper GEC that must be run to it?
a.4 AWG
b.6 AWG
c.2 AWG
d.1/0 AWG
Giải thích
Per 250.66(B), where the GEC connects solely to a concrete-encased electrode, it need not be larger than 4 AWG copper. 6 AWG is the cap only for rod/pipe/plate electrodes; 2 AWG and 1/0 exceed the concrete-encased allowance.
Trích dẫn luật: 2023 NEC §250.66(B)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- A 200 A service uses 250 kcmil copper ungrounded service-entrance conductors. Per Table 250.66, what is the minimum copper grounding electrode conductor (GEC)?
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