wire for hanging florescent light fixtures

[LutzTD]

I am finally running wire in the second phase. I can do some of the lights which according to my layout wont be moved. These will hang from a 21-18 ft roof and the lights will be at 12 feet, so the lights will need 6-9ft of wire from the boxes mounted on the ceiling. I am going to hang the light with 060" steel cable. So can I use romex from the electrical boxes to the light and tie it on the cable or do I need to use cord wire or something?

 

[tshetter]

You can use SJOOW rated cable or MC cable, these are the typical methods used in an industrial setting.

Is your ceiling finished with drywall?

 

[Shiftless]

I vote for the metal clad cable.

 

[Norcal]

You can use SJOOW rated cable or MC cable, these are the typical methods used in an industrial setting.

Is your ceiling finished with drywall?

I vote for the metal clad cable.

Unless a plug is used & then GFCI protection is required cord can't be used. MC uses solid conductors, code requires stranded in the OP's application, 1/2 Greenfield w/ stranded conductors is a compliant method.

 

[tshetter]

Unless a plug is used & then GFCI protection is required cord can't be used. MC uses solid conductors, code requires stranded in the OP's application, 1/2 Greenfield w/ stranded conductors is a compliant method.

You know I have never heard that before. Any chance you know the code section for that?

I have also never run into MC with solid conductors it has always been stranded.

 

[Norcal]

400.8(1), flexible cord not to be used as a substitute for the fixed wiring of a structure, also 410.62(C)(1). 410.56(E) for stranded conductor requirement.

 

[Aceman]

MC uses solid conductors, code requires stranded in the OP's application

We use stranded MC for hardwired fixtures.

https://www.platt.com/platt-electri...le/122MCAGGRESTRX250/product.aspx?zpid=302723

 

[LutzTD]

We use stranded MC for hardwired fixtures.

https://www.platt.com/platt-electri...le/122MCAGGRESTRX250/product.aspx?zpid=302723

awesome thanx, that makes sense. Next question is the wire gauge. I plan to have 8 fixtures for the section I can do now. This would be 4 bulb high output t5 fixtures. I can run multiple 20A lines if needed but prefer to keep this section on 1 switch. Since its 20 amp do I size the wire for each fixture to 20 amp? Would it be better to do less fixtures on a couple 15amp and use smaller wire?

 

[Aceman]

Would it be better to do less fixtures on a couple 15amp and use smaller wire?

Yes.

 

[theoldwizard1]

400.8(1), flexible cord not to be used as a substitute for the fixed wiring of a structure, also 410.62(C)(1). 410.56(E) for stranded conductor requirement.

The last batch of 4' fluorescent fixture I bought all came with cords.

 

[Stuart in MN]

The last batch of 4' fluorescent fixture I bought all came with cords.

Assuming they were cords with plugs on the ends they aren't considered fixed wiring, so the cited NEC sections wouldn't apply.

 

[theoldwizard1]

Assuming they were cords with plugs on the ends they aren't considered fixed wiring, so the cited NEC sections wouldn't apply.

So if I have a florescent fixture that did NOT come with a cord from the factory, you are saying I can not add one ? Sounds like BS to me.

I have added 3 wire power cords to garbage disposers, dishwasher and oven hood/microwave/fan/light and never had an inspector blink. Disposer and dishwasher were on GFCI.

 

[justsam]

You will need to check the current draw of your proposed fixtures.

Eight of them on a 15 Amp circuit may be too much, especially if an 80% rule is applied, which it should be.

Best to break things into two circuits to give you flexibility, if not, go to 20 Amp circuit, assuming current draw is under 16 Amps.

 

[wyliesdiesels]

400.8(1), flexible cord not to be used as a substitute for the fixed wiring of a structure, also 410.62(C)(1). 410.56(E) for stranded conductor requirement.

Whats funny is i work in a lot of industrial plants and i constantly see the plant "electricians" using cordage to wire lighting that is hardwired to j boxes- no plug or GFCI. Amazing how many plants dont care about codes. And this is all 480v/277v. U would think people would pay more attention to codes and electrical wiring when working with higher voltages.

 

[wyliesdiesels]

awesome thanx, that makes sense. Next question is the wire gauge. I plan to have 8 fixtures for the section I can do now. This would be 4 bulb high output t5 fixtures. I can run multiple 20A lines if needed but prefer to keep this section on 1 switch. Since its 20 amp do I size the wire for each fixture to 20 amp? Would it be better to do less fixtures on a couple 15amp and use smaller wire?

U need to know the draw of each fixture.

Also, the wire needs to be sized based on thr OCPD rating NOT the fixture rating.

20a circuit needs to be wired with #12.

Also, lighting is considered a continous load so total fixture load cannot be more than 80% of circuit rating. For 20a, this means 16a.

So if I have a florescent fixture that did NOT come with a cord from the factory, you are saying I can not add one ? Sounds like BS to me.

I have added 3 wire power cords to garbage disposers, dishwasher and oven hood/microwave/fan/light and never had an inspector blink. Disposer and dishwasher were on GFCI.

nope. Read the code again. U can add a cord but it needs to have a plug on it and be plugged into a GFCI protected outlet- essentially it cant be hardwired, doing so would make it part of the permanent building wiring.

 

[Aceman]

Which code says I can't use cord on a jack chain hung fixture, whether it has a cord end on it or not?

 

[wyliesdiesels]

Which code says I can't use cord on a jack chain hung fixture, whether it has a cord end on it or not?

Norcal already posted it above - 400.8(1)

 

[Aceman]

Norcal already posted it above - 400.8(1)

I think you're misunderstanding the intent of that code article. Take a look at 400.7(A)2.

 

[LutzTD]

U need to know the draw of each fixture.

Also, the wire needs to be sized based on thr OCPD rating NOT the fixture rating.

20a circuit needs to be wired with #12.

Also, lighting is considered a continous load so total fixture load cannot be more than 80% of circuit rating. For 20a, this means 16a.



nope. Read the code again. U can add a cord but it needs to have a plug on it and be plugged into a GFCI protected outlet- essentially it cant be hardwired, doing so would make it part of the permanent building wiring.

this is what I was looking for. On the first phase the fixtures were surplus desk lights so they all had cords. I put 8 4 bulb fixtures on one 20 amp circuit. The circuit breaker was GFCI and the electrical run was 4 2way outlets which had 2 fixture plugged into each one. The only difference is I believe the cords were rated for the fixture not the breaker. Im going to see if I can find some cheap cords with plugs rated for the amperage of the lamp and then run outlets like the first phase. Makes it more flexible too.

 

[LutzTD]

what about something like this? I can do this and a $.50 strain relief and it would be cheaper than the shielded wire.

 

[pattenp]

Norcal already posted it above - 400.8(1)

That is for building wiring such as from the panel to the outlet box to where the lighting fixture is connected.

I think you're misunderstanding the intent of that code article. Take a look at 400.7(A)2.

You are correct. You can go in to many industrial styled restaurants etc. and see hanging strip fluorescent light fixtures wired with cord to a ceiling mounted box.

 

[LutzTD]

I bought 10 each of these. little more expensive than chinese but local. If they work out ill bulk order the rest