Branch Circuits & WiringQuestion 184 of 521
In a box-fill calculation, a single device (a receptacle or switch mounted on a yoke or strap) counts as how many conductor volume allowances?
a.1
b.0
c.3
d.2
Explanation
Per 314.16(B)(4), each yoke or strap containing one or more devices counts as two volume allowances, based on the largest conductor connected to the device. Counting it as 1 or 0 understates the fill; a standard single device is not 3.
Law Reference: 2023 NEC §314.16(B)(4)Practice all 521 questions free — no signup required.
Related questions on this topic
- 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?
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