mc cable support

Status
Not open for further replies.
C

cmreschke

Senior Member
Installing troffer lay in fixtures and feeding with mc. Light is supported by grid wire on opposite corners. Is it a violation to secure mc cable to the supported fixture. I don't think it is or should be but don't have a book handy here to look it up.
 
i remember someone telling me that you cannot support cables by the prehung ceiling wire but cnt find the nec art
 
Yeah I know that myth or not I'm dropping wires for my fixtures. I want to support my mc cable from my fixtures themselves 1 hole strap to the light.
 
If you dropped two of your own wires to the light you can batwing to those. But not to the actual wires supporting the grid. If you use those snap in Arlington connectors you can have a six foot whip with ZERO strapping required. A whip any longer than that and you need a strap no farther than 6' from the light. Most of the time troffers are pretty close together so I just batwing to the wires tied to the fixtures. If I have a long ways to go I'll shoot extra wires just to hang MC from.
 
jumper said:
I do not see any violation of 330.30 in doing this.
Click to expand...

the only non code issue I see the screws that hold the straps down will punch through the bottom side showing up on the bulb side.
 
cmreschke said:
That's not what I'm asking.......
Can one support mc cable from a supported lay in troffer fixture?
Click to expand...

Why would you want to one hole strap to the top of a troffer? You'd rather carry an impact, a screw, and a strap up the ladder instead of just a batwing?
 
Cow said:
Why would you want to one hole strap to the top of a troffer? You'd rather carry an impact, a screw, and a strap up the ladder instead of just a batwing?
Click to expand...

Must be a unique situation. It's difficult to imagine one where the batwing method would not be superior.
 
330.30(D)(2) states: if not more than 6' in length from the last point of cable support to the point of connection to luminaries or other electrical equipment and the cable and point of connection are within an accessible ceiling. For the purpose of this section, Type MC cable fittings shall be permitted as a means of cable support.
 
If you're going into the top of the fixture I would think that would make for a very tight bend with the MC cable (remember there is a bending radius) and you would stand the chance of running a screw into one of the wires inside of the fixture.

I also thing the batwing is the way to go.
 
Status
Not open for further replies.
Top