Mạch nhánh & Đi dâyCâu 182 / 521
Using the same 21.0 in³ box with no other fill allowances, what is the maximum number of 12 AWG conductors permitted?
a.10
b.9
c.8
d.7
Giải thích
Each 12 AWG conductor requires 2.25 in³ per Table 314.16(B). 21.0 ÷ 2.25 = 9.33, rounded down to 9 conductors. 10 would exceed the volume, and 8 or 7 undercounts.
Trích dẫn luật: 2023 NEC §314.16(B)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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