- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I know we have talked about this but this change seems absurd. As I read this it seems to say the volume marked in these plastic boxes is not the true volume so we have to deduct the clamp intrusion into the box but we don't have to count the intrusion as 1 conductor. If this is so why doesn't the manufacturer just mark the box with the actual volume of available space. Am I reading this correctly?
314.16(B)(2) Clamp Fill. Where one or more internal cable clamps,
whether factory or field supplied, are present in the box, a
single volume allowance in accordance with Table 314.16(B)
shall be made based on the largest conductor present in the
box. No allowance shall be required for a cable connector with
its clamping mechanism outside the box.
A clamp assembly that incorporates a cable termination
for the cable conductors shall be listed and marked for use
with specific nonmetallic boxes. Conductors that originate
within the clamp assembly shall be included in conductor fill
calculations covered in 314.16(B)(1) as though they entered
from outside the box. The clamp assembly shall not require a
fill allowance, but the volume of the portion of the assembly
that remains within the box after installation shall be excluded
from the box volume as marked in 314.16(A)(2).