Thiết bị & Hệ thốngCâu 259 / 521
An A/C condensing unit has a compressor rated-load current of 18 A and a fan motor of 2 A. Using the 125%-of-largest-motor-plus-others method, what is the minimum circuit ampacity (MCA)?
a.20 A
b.25 A
c.24.5 A
d.27.5 A
Giải thích
MCA = 125% of the largest motor + sum of the other loads: (18 x 1.25) + 2 = 22.5 + 2 = 24.5 A. 20 A omits the 125% factor, 25 A applies 125% to the whole 20 A, and 27.5 A applies 125% to both loads.
Trích dẫn luật: 2023 NEC §440.33Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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