Services, Grounding & BondingCâu 37 / 120
What is the minimum size copper equipment grounding conductor for a 400-ampere feeder?
a.4 AWG
b.3 AWG
c.2 AWG
d.1 AWG
Giải thích
Table 250.122 lists 3 AWG copper at 400 amperes. 4 AWG is the 300-ampere value, 2 AWG the 500-ampere value and 1 AWG the 600-ampere value, so all three are one row away from the correct entry.
Trích dẫn luật: 2023 NEC Table 250.122Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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