Thiết bị & Hệ thốngCâu 256 / 521
A single hermetic refrigerant motor-compressor has a rated-load current of 24 A. Per NEC 440.32, what minimum branch-circuit conductor ampacity is required?
a.24 A
b.26 A
c.28.8 A
d.30 A
Giải thích
NEC 440.32 requires conductors for a single motor-compressor to be sized at 125% of the rated-load current or branch-circuit selection current, whichever is larger: 24 x 1.25 = 30 A. 24 A omits the factor, 26 A is ~108%, and 28.8 A is 120%.
Trích dẫn luật: 2023 NEC §440.32Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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