Drivers in junction boxes

[jimport]

I have not seen anything pending changes regarding this. Today I was installing led fixtures that had a separate driver that needs to mount in the 8B above the mounting bracket or plate. Short little leads and tough to fit even with just 2 cables in the box. Seems like a poor design that is not addressed with box fill.

 

[letgomywago]

I've installed something like that they were not fun and it was only a fixture swap but they had an old 3o box and it didn't fit in there anyway so now they have a 4o and it's still crazy tight.

 

[James L]

About 7 years ago I installed some Patriot Lighting disk lights with separate drivers like that. Incredibly tight. I don't know how anyone could figure there was enough box space

 

[letgomywago]

About 7 years ago I installed some Patriot Lighting disk lights with separate drivers like that. Incredibly tight. I don't know how anyone could figure there was enough box space

I've found ones since not as bad at all the diver is in the fixture space exclusively.

 

[garbo]

Came across this another cheating china product a few years ago. Told our boss that I would rather the drivers into a 4 &11 & 16" derp box but he insisted just to install it in the 4" octagon ceiling box. Was very tight even with using the 2 & 1/8" deep boxes. The NEC should require manufactures to install a label on these letting you know the cubic inches it takes up and cross reference how many #12 & 14 conductors to add when figuring out box fill calculation.

 

[don_resqcapt19]

Came across this another cheating china product a few years ago. Told our boss that I would rather the drivers into a 4 &11 & 16" derp box but he insisted just to install it in the 4" octagon ceiling box. Was very tight even with using the 2 & 1/8" deep boxes. The NEC should require manufactures to install a label on these letting you know the cubic inches it takes up and cross reference how many #12 & 14 conductors to add when figuring out box fill calculation.

Good idea for a Public Input to make changes for the 2026 code. The system should open up for the submission of PIs in a month or so. It will be at nfpa.org/70 then click on next edition.

They did add something along that line to 314.16(B) in the 2023 code for terminal blocks.

(6) Terminal Block Fill.
Where a terminal block is present in a box, a single volume allowance in accordance with Table 314.16(B)(1) shall be made for each terminal block assembly based on the largest conductor(s) terminated to the assembly.

 

[letgomywago]

I feel like adding alot of complexity to the methods of box fill will just make alot of confusion. Just adding the requirements for more than 3 grounds being counted as 0.25 fill makes people upset. There must be a different way ti address this like with the UL listing for driver based lights or something.

 

[don_resqcapt19]

I feel like adding alot of complexity to the methods of box fill will just make alot of confusion. Just adding the requirements for more than 3 grounds being counted as 0.25 fill makes people upset. There must be a different way ti address this like with the UL listing for driver based lights or something.

Even with a change in the product (listing) standard, you would need a change in the code itself.

 

[jimport]

It would be better if the fixtures came with a deep canopy or so other means to add additional volume without jamming the junction box.

 

[steve66]

Are these LED drivers? Are u sure they need to go in a box? Many new “wafer“ lights have a box that can just be left above the ceiling. They make the drivers separate from the LED’s to keep the heat away from the LED‘s.

 

[letgomywago]

Are these LED drivers? Are u sure they need to go in a box? Many new “wafer“ lights have a box that can just be left above the ceiling. They make the drivers separate from the LED’s to keep the heat away from the LED‘s.

It's in fixtures like this. They are available for flattish cans but those styles have begun to dissappear with the introduction of wafer lights now I've heard that the intentional use of them is when fire rating is desired for the ceiling and the fire rated cans are too expensive.

 

[tortuga]

When I had to design a job with those I just figured the cubic inches of the driver multiplied by 1.5
So if the driver took away 6 cubic inches from the boxs I'll add 9 to the fill.
4&11 boxes with a 3/0 mud ring usually work.