Branch Circuits & WiringQuestion 186 of 521
A box has four 12 AWG equipment grounding conductors entering it. How are they counted in the box-fill calculation?
a.Each counts individually (four allowances)
b.All together count as a single volume allowance
c.They are never counted
d.They count as two allowances
Explanation
Per 314.16(B)(5), all equipment grounding conductors together count as a single volume allowance, based on the largest EGC present. Counting them individually overstates the fill, and they are not exempt from the calculation.
Law Reference: 2023 NEC §314.16(B)(5)Practice all 521 questions free — no signup required.
Related questions on this topic
- Per Table 314.16(B), what is the free-space volume allowance required for a single 12 AWG conductor?
- 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 box contains three internal cable clamps. In the box-fill calculation, how many volume allowances do the clamps require in total?
- 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 single unbroken conductor passes straight through a box without being spliced or terminated. For box fill, it is counted as how many conductors?
- How are conductors that both originate and terminate within the box (such as short pigtails or jumpers) treated in a box-fill calculation?
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