Branch Circuits & WiringQuestion 181 of 521
A 4" x 1-1/2" square box has a volume of 21.0 in³. With no clamps, devices, or other allowances, what is the maximum number of 14 AWG conductors permitted in the box?
a.10
b.9
c.11
d.8
Explanation
Each 14 AWG conductor requires a 2.00 in³ volume allowance from Table 314.16(B). 21.0 ÷ 2.00 = 10.5, and you round down to 10 conductors. Rounding up to 11 would exceed the box volume, and 9 or 8 understates the count.
Law Reference: 2023 NEC §314.16(B)Practice all 521 questions free — no signup required.
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