Wiring Methods & MaterialsCâu 67 / 120
What is the minimum burial cover for a nonmetallic raceway listed for direct burial without concrete encasement, installed under a lawn?
a.18 inches
b.6 inches
c.24 inches
d.12 inches
Giải thích
Listed nonmetallic raceways buried without concrete encasement require 18 inches of cover in locations not otherwise specified. Metal conduit needs only 6 inches, direct-buried cable needs 24 inches, and 12 inches applies to GFCI-protected 120-volt residential branch circuits.
Trích dẫn luật: 2023 NEC Table 300.5Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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