Branch Circuits & WiringQuestion 187 of 521
A box contains five 12 AWG current-carrying conductors, one 12 AWG equipment grounding conductor, one internal cable clamp, and one switch on a yoke (all conductors 12 AWG). What total box volume is required?
a.18.00 in³
b.15.75 in³
c.20.25 in³
d.22.50 in³
Explanation
At 2.25 in³ each: five conductors = 11.25, EGCs (as one) = 2.25, clamp (as one) = 2.25, and the yoke = 2 × 2.25 = 4.50. Total = 11.25 + 2.25 + 2.25 + 4.50 = 20.25 in³. The other values omit one or more required allowances.
Law Reference: 2023 NEC §314.16(B)Practice all 521 questions free — no signup required.
Related questions on this topic
- 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?
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