Dịch vụ & Phân phốiCâu 107 / 521
Service-entrance conductors installed in a raceway in a wet location (such as underground or exposed to weather) must be:
a.Any dry-rated conductor is acceptable
b.Bare copper only
c.Type TW without a jacket
d.Listed and marked for wet locations, such as RHW, THW, THWN, or XHHW
Giải thích
Per 310.10(C), conductors in wet locations (including raceways underground or exposed to weather) must be a type listed for wet locations, such as RHW, THW, THWN, or XHHW. Dry-only types or bare conductors are not permitted where moisture is present.
Trích dẫn luật: 2023 NEC §310.10Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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