314.16 vs 110.3(B)

[chris kennedy]

I have a couple hundred high hats, and the wiring compartments state maximum 4 #12 conductors. The junction box itself measures 2? x 3? x 1? = 13 cubes. 5 #12s = 12.5 cubes. Nothing else in this wiring compartment except the 3 # 18 fixture wires. In some situations, I have a couple dozen high hats on one switch light. So I need to install a large junction box and take one two wire MC to each fixture???

I believe the manufacturers are not counting the grounding conductors in their box fill. Also, many of these luminaries require 12 inches of slack cable so that the ballast can be pulled down through the aperture for service, violation of 330.30? This means also I can't use EMT to get only 4 conductors.

These high hats are manufactured by USAI. I'm putting two 12/2's into these. Anybody run into this before?

 

[benaround]

chris,

With that amount of fixtures, it might be worth it to call the manafacturer to get right info.

 

[iwire]

Type AC cable or MCAP comes to mind.

 

[chris kennedy]

chris,

With that amount of fixtures, it might be worth it to call the manafacturer to get right info.

Of coarse thats the next move, to late today when I discovered this.

 

[raider1]

Type AC cable or MCAP comes to mind.

I agree.

Chris

 

[chris kennedy]

Type AC cable or MCAP comes to mind.

I agree.

Thats special order around here. I find it absolutely absurd that I can't take two 12/2's with EGC into a wiring compartment that is clearly large enough.

 

[benaround]

chris, You are concerned about the 12" to the box securing ?

 

[iwire]

Thats special order around here.

I never realized you lived in Liechtenstein.

Maybe the intention is a single piece of FMC?

 

[kwired]

I have a couple hundred high hats, and the wiring compartments state maximum 4 #12 conductors. The junction box itself measures 2? x 3? x 1? = 13 cubes. 5 #12s = 12.5 cubes. Nothing else in this wiring compartment except the 3 # 18 fixture wires. In some situations, I have a couple dozen high hats on one switch light. So I need to install a large junction box and take one two wire MC to each fixture???

I believe the manufacturers are not counting the grounding conductors in their box fill. Also, many of these luminaries require 12 inches of slack cable so that the ballast can be pulled down through the aperture for service, violation of 330.30? This means also I can't use EMT to get only 4 conductors.

These high hats are manufactured by USAI. I'm putting two 12/2's into these. Anybody run into this before?

5 # 12's is 11.25 cu in not 12.5. add two #18 and you are still over though.

 

[chris kennedy]

chris, You are concerned about the 12" to the box securing ?

No sir, this is one place I will not enforce 330.30.

I never realized you lived in Liechtenstein.

Maybe you should pay more attention. Your welcome to visit any time, in fact I have a DOH job you could knock out while your here.

 

[chris kennedy]

Mind if I bump this, still bugging me and didn't have time to contact the manufacture today.

Thanks

 

[augie47]

appears their calculations are correct, does it not:

2-1/2 x 3-1/2 x 1-/12 = 13.1 cu in
1 3 #18 @ 1.5 - 4.5
8.6
8.6 remainer / 2.25 = 3.8 or 4 #12 s

 

[chris kennedy]

Crap, I wasn't counting the fixture wires but I see in this case I must.

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.