Mạch nhánh & Đi dâyCâu 146 / 521
Per Table 300.5, what is the minimum cover for direct-buried UF cable (without other protection) not under a driveway, in a residential branch circuit application?
a.6 in
b.12 in
c.24 in
d.36 in
Giải thích
Table 300.5 requires 24 in of cover for direct-buried cables and conductors in the general burial column. A GFCI-protected residential 120-V, 20-A branch circuit may be reduced to 12 in, but the base direct-burial requirement is 24 in. 6 in is far too shallow; 36 in is not required in this row.
Trích dẫn luật: 2023 NEC §300.5Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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