Dịch vụ & Phân phốiCâu 87 / 521
A feeder supplies a single continuous load of 100 A. The minimum feeder conductor ampacity and overcurrent device rating is:
a.100 A
b.110 A
c.115 A
d.125 A
Giải thích
For a continuous load, both the conductor ampacity and the overcurrent device must be at least 125% of the load: 100 x 1.25 = 125 A. Selecting 100 A ignores the continuous-load factor entirely, and 110 A/115 A fall short of the required 125%.
Trích dẫn luật: 2023 NEC §215.2Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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