Dịch vụ & Phân phốiCâu 25 / 521
What is the maximum overcurrent protection allowed for a 12 AWG copper conductor under the small-conductor rule?
a.20 A
b.25 A
c.30 A
d.15 A
Giải thích
Per 240.4(D), 12 AWG copper is limited to 20 A regardless of its higher table ampacity. 15 A is the 14 AWG limit, and 25 A or 30 A exceed the small-conductor cap for 12 AWG.
Trích dẫn luật: 2023 NEC §240.4(D)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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