Lighting/Fan Canopy

Little Bill said:
Does the canopy for a light fixture, or ceiling fan, add to the box fill volume?
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The first sentence of (2017) 314.16(A) on Box Volume Calculations is (bolding by me:

2017 NEC 314.16(A) said:
The volume of a wiring enclosure (box) shall be the total volume of the assembled sections and, where used, the space provided by plaster rings, domed covers, extension rings, and so forth, that are marked with their volume or are made from boxes the dimensions of which are listed in Table 314.16(A).
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I would think that canopies would count as "domed covers." The canopy would need a volume marking. Unspecified is whether the marking needs to come from the manufacturer, or if you can measure the volume and mark it yourself. : - )

Cheers, Wayne
 
Question came up for a fan rated pancake box as to whether the pancake box had enough volume for box fill if more cables are there than just for the fan. I've done this before and just figured the canopy would cover any overfill of the pancake. Never been called on it.
 
The exception to 314.16(B)(1) seemingly helps in regard to the conductors smaller than #14.
Exception: An equipment grounding conductor or conductors or not over four fixture wires smaller than 14 AWG, or both, shall be permitted to be omitted from the calculations where they enter a box from a domed luminaire or similar canopy and terminate within that box.

I have noticed here that conductor fill with #14's on pancake boxes is often overlooked when there is a canopy etc even if it ism not marked with volume.
 
kwired said:
Do they have enough volume for more than one cable entry is the million dollar question and/or will you be limited to 14 AWG if you want to comply?
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The upper one clearly shows 8) 14s, 7) 12s, or 6) 10s; the lower one has the same numbers.
 
LarryFine said:
The upper one clearly shows 8) 14s, 7) 12s, or 6) 10s; the lower one has the same numbers.
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I see that now. Doesn't seem possible to have 16 cubic inches unless it has a lot more depth than it appears to have. Typical round nail on box without the center portion taken away is often only 18 cubic inches, some maybe 20.
 
While we are on the plastic box subject Arlington makes one that is fan rated round plastic nail on 35#fan or 50# fixture #9350 Arlington. What crap and it only has 8/32 screws. I know I am old school but I couldn't make myself put a fan on one of those

A standard metal octagon with a bar hanger and not fan rated is stronger than that crap. Seems to me a little wiggle could pull the nails out. before fan rated boxes were even created that is what we used. You could always drill and tap the ears for 10-32.
 
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ActionDave said:
Arlington plastic fan boxes don't use 8-32 screws to support the fan, that would not be allowed. They use wood screws that support the fan independent of the box.
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There is one it's rated for fans of 35lbs or less and it's made of fiberglass. I use it when nec says it needs to be fan rated but I know better. Like in a basement where the ceiling is only 7 and half feet but it's in the center of a room.
 
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