Custom Light Fixture

[osumet]

I'm getting ready to build a custom light fixture that will be made from 4 pendant lights. I'm planning on building a shallow box out of wood and mounting the box to the ceiling. The wood box will effectively be the base of my light fixture. The wood box will be mounted over an existing round metal junction box that's recessed in the ceiling. The pendant lights will be mounted to the wood box and connected in series inside of the wood box. I'm aware that the NEC rules require that all splices be made inside an electrical box but what about splices inside the base of my wood light fixture? Do I need to install a shallow metal box inside the base of my light fixture to make the splices?

See attached image for further explanation. Do I need to install a metal electrical box at the junctions of the red and green lines as shown in the picture?

Nathan

 

[Shiftless]

Do you expect to be subjected to a formal electrical inspection?
Is this for your own use or are you selling it to a customer or ???
I am not an electrician but from what I understand...
Your hypothetical home made metal box is not a listed enclosure so it doesn’t conform to code.

 

[Lelandwelds]

People sell light fixtures made from old Mason jars, fence posts, and milk cans all the time. Let it rust, call it "art" and you can ask a bigger price.

 

[osumet]

Do you expect to be subjected to a formal electrical inspection?
Is this for your own use or are you selling it to a customer or ???
I am not an electrician but from what I understand...
Your hypothetical home made metal box is not a listed enclosure so it doesn’t conform to code.

It will not be subject to an electrical inspection and is for my home that I own. What would I need to do to meet code? I updated the original post with an image that provides a better explanation.

 

[The Cobbler]

I expect if you used romex or bx and used octagon electrical boxes for each lamp, and a cover at the existing box you would be code compliant.
that way your wood box is not a light fixture per sai.

 

[Crazyjake8493]

I think the only issue is with the wood enclosure as part of the fixture is a combustible material. I wouldn't make them to sell or have your inspector over for dinner, but it should be fine for what you're trying to do.

 

[Crazyjake8493]

I expect if you used romex or bx and used octagon electrical boxes for each lamp, and a cover at the existing box you would be code compliant.
that way your wood box is not a light fixture per sai.

This is how I would do it, with a separate metal box over each light, and I'd even connect them with MC or EMT, but as long as the splices are made in a listed enclosure, the wood is just trim and not technically part of the fixture.

 

[Lelandwelds]

In my youth, I knew a young lady with a ceiling lamp made from strings of macaroni. I have seen taxidermy lamps. Have you ever looked at lamps on pinterest or etsy?

Tacky but code enforcement will not be knocking down your door. Not even in Chicago.

 

[markhm]

The box must be metal lined and there must be metal pipe in holes between lights and box liner to be acceptable.

 

[markhm]

Forgot to add that there also has to be a metal cover for the box against all sides of wood and the ceiling, too.

 

[osumet]

I expect if you used romex or bx and used octagon electrical boxes for each lamp, and a cover at the existing box you would be code compliant.
that way your wood box is not a light fixture per sai.

This is how I would do it, with a separate metal box over each light, and I'd even connect them with MC or EMT, but as long as the splices are made in a listed enclosure, the wood is just trim and not technically part of the fixture.

This makes sense. I think I'll do as y'all suggested and use some armored cable, install boxes at each fixture and a put a cover over the existing one.

Appreciate all of the help!

 

[yeldogt]

I'm sure if you were going for UL certification you would need the connections in some form of junction box ... my thought because of the wood case. Although, there are wood lamps. Lighting is strange -- I have seen all manner of connections -- including those you can't get to after the light is assembled.

Having built many over the years. If the wires are long enough for two to join up together you could use two central boxes and then two sets of wires to the ceiling box.

If the wires are too short -- I would just do the connection under the canopy.

Could aways cut round holes and use the pancake boxes -- I know have seen this with a plastic sleeve through the wood and crimped connectors someplace.

 

[ard]

Why worry about 'code'?

There are many methods one can use that are not 'code compliant' which would nonetheless be perfectly safe AND could pass UL certification.

I'd focus on building a safe light, not making it NEC compliant.

 

[osumet]

Why worry about 'code'?

I asked what I needed to do in order to meet code because I don't know all of the safe practices. My understanding of the NEC is that it outlines those safe practices so that I don't have to re-discover them for myself.

National Electric Code = safe practices

safe practices = National Electric Code + any practice that has been proven not to adversely affect an electrical system but may or may not ever be included in the NEC handbook

 

[markhm]

The NEC essentially says that lighting has to meet relevant standards, and the NEC doesn't provide the standards. It is referring to UL standards as they are the only approved standards for lighting in USA. UL standards are mostly common sense and they are developed with input from the lighting manufacturers. Where UL gets slightly more burdensome, is that they not only want to make sure that fixtures are safe, they also want to make sure that when a fixture fails or there is some kind of bad event to its environment, the fixture wont cause further harm or will cause minimal harm. That is why in your case, UL insists that the wireways are completely enclosed in metal and grounded. They don't want that if too much current is run thru the wires due to a fault, it will overheat the adjacent combustible material starting a fire and if the insulation is degraded on the wires, they want it to ground out against the metal and trip a breaker. Understand that safety is not just making something safe under standard conditions but also making safe as possible when things go bad.

 

[yeldogt]

I asked what I needed to do in order to meet code because I don't know all of the safe practices. My understanding of the NEC is that it outlines those safe practices so that I don't have to re-discover them for myself.

National Electric Code = safe practices

safe practices = National Electric Code + any practice that has been proven not to adversely affect an electrical system but may or may not ever be included in the NEC handbook

I don't believe the NEC gets into lighting -- same with internals of equipment. Your light idea in metal or plastic would have simple grommet for each set of light wires and crimp connectors above .. no different than a FL tube fixture or a multi bulb vanity light.

 

[osumet]

Thanks for the respones, Markhm. The more I learn about the NEC requirements the more I realize just how little I know about it. I agree that many of the NEC, UL, etc. codes are are common sense, probably more so to you than I, but not to most. Common sense is sound practical judgement derived from experience rather than study. Personally, I don't have much electrical experience so I tend to rely on someone else that has much more experience than I. Things that seem common sense to me, as a mechanical engineer, may not be common sense to someone outside of my field.

Thanks,
Nathan

 

[osumet]

I don't believe the NEC gets into lighting -- same with internals of equipment.

Thanks for the clarification, yeldogt. I haven't a clue which codes organization deals with the codes for light fixtures so when I've mentioned NEC I'm simply referring to some set of standards out there that have something to do with the safety of the light fixtures that we all install in our garages/houses, haha.

Regards,
Nathan

 

[The Cobbler]

I don't believe the NEC gets into lighting -- same with internals of equipment.

true, but UL or other agencies approve it for use.

 

[Radix2]

Do as is commonly done in UL light fixtures - bring the pigtails from every socket back to the ceiling box, no splices are then required in your fixture.

 

[Shiftless]

How would the rules change if the bulbs were 12 volt LED bulbs? A guy could then power the home made fixture with a UL approved transformer placed inside a large junction box.
If I recall, the rules for low voltage fixtures are way less strict. Think of landscape lighting connectors and all the flammable enclosures involved with that industry.

 

[yeldogt]

Do as is commonly done in UL light fixtures - bring the pigtails from every socket back to the ceiling box, no splices are then required in your fixture.

The multi bulb surface mounted bathroom vanity lights have all the connections in the case holding the bulbs .. often two of the bulbs together linked to the next two -- typical two wires and ground out to the ceiling box.

It's most likely the wood case in the OP's setup that is a question. Have made many custom lights out of wood and wired as above. Guessing if selling commercially -- UL would require the connection to be separated from the wood?

In reality -- it's a tiny danger if properly crimped>