Mạch nhánh & Đi dâyCâu 148 / 521
Branch-circuit conductors must have an ampacity not less than the maximum load to be served and, before the application of adjustment or correction factors, not less than what portion of the continuous load?
a.125 percent
b.100 percent
c.80 percent
d.150 percent
Giải thích
Section 210.19(A) requires branch-circuit conductors to be sized at not less than 125 percent of the continuous load plus 100 percent of the noncontinuous load. This margin accounts for heat buildup under sustained load. 100 and 80 percent are too small; 150 percent is more than the code requires.
Trích dẫn luật: 2023 NEC §210.19(A)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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