Box Fill

[erdy7821]

When Calculating box fill on a ceiling box, if the fixture is flush with the ceiling and attaches
with screws through the fixture into the box do you add any conductors for these when adding up box fill? Also what if a mounting bracket is used?

 

[hbiss]

Re: Box Fill

Yes, each wire and one for the bracket.

 

[al hildenbrand]

Re: Box Fill

By fixture bracket, do you mean the flat strap that lays on the surface of the outlet openning? Or is the "bracket" a stud or hickey inside the box?

314.16(B)(3) only mentions studs and hickeys.

My IEEE dictionary defines hickey as

A fitting used to mount a lighting fixture in an outlet box or on a pipe or stud. Note: It has openings through which fixture wires may be brought out of the fixture stem.

 

[hbiss]

Re: Box Fill

I guess the bracket or mounting plate could be a gray area. If it is completely flat, mounts to the box and with only a couple of screws supports the fixture then I would say not to count it. If it dips into the box as some do and/or uses a nipple in the center to mount the fixture then I would count it. Of course hickeys in the box must be counted.