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Posted By: windmiller Light Fixtures - 01/11/07 03:12 PM
Hi,
Is there a article in the code that covers the size of the supply conductors for a fluorescent light fixture?

I was thinking there was.

I have some fixtures with a 16/3 SO cord from the manufacturer that would be fed from a 20 A circuit via twist lock.

Thanks for any info.

Windy
Posted By: earlydean Re: Light Fixtures - 01/11/07 03:52 PM
240.5(B)(4)
Posted By: windmiller Re: Light Fixtures - 01/11/07 04:29 PM
Thanks for the reference.

I read the article but they wrote that so that it is not very clear.

I am guessing that a light fixture is an appliance but the rest is not so clear.

The light fixture might draw 1.5 amps, that does'nt tell me much about the circuit feeding the fixture.

Can anyone clear this up?

I am talking about the SO cord feeding the fixture. It came from the factory with the cord attached.

I am pretty sure that a 16/3 SO cord would be allowed on a 20 A circuit. Am I right?

Thanks

Windy
Posted By: renosteinke Re: Light Fixtures - 01/11/07 06:46 PM
The code actually does have some specific provisions for lighting fixtures (or Luminaires).

There are a few thing to also consider.

A cord that is factory installed is considered part of the appliance, and the NEC generally does not apply to the parts of an appliance.

That said, 'lighting whips' are addressed by some code sections. 402.5 suggests that even #18 can be acceptable.

There is likewise a provision in the NEC that alows lighting circuits to be as large as 50 amps. I really doubt there are any fixtures out there with #6 wires passing through them; the final six foot run is commonly a conductor smaller than the branch circuit conductors.
Posted By: earlydean Re: Light Fixtures - 01/11/07 08:42 PM
What do you mean it is hard to understand?????:
"20-ampere circuits - 16 AWG and larger" cords are allowed.

There is also 240.5(B)(1) and 410.30(C)(1). If you have a listed fixture or appliance with an attached cord that fits into a 15 or 20 amp 120 volt receptacle, then the cord size will be dandy.

If you have some non-listed fixture or appliance, then one had better take a closer look.
Posted By: SolarPowered Re: Light Fixtures - 01/11/07 08:53 PM
From a safety point of view, it is very difficult to create a situation where a light fixture can draw more current than is safe in 16 gauge cord, but still less than enough to trip a 20 amp breaker. Typically you're either going to be drawing around the normal amount for fixture, or else somewhere around a dead short.

The code appears to take this into account in the cord and the tap rules.

This is presumably part of why receptacle adaptors that screw into an Edison-base socket are frowned upon. And also why outlet strips do require built-in circuit breakers--it is well within the realm of possibility that someone can plug enough things into the strip to overload the cord, but not the circuit.
Posted By: windmiller Re: Light Fixtures - 01/11/07 09:50 PM
thanks for the replies...

Earlydean....just trying to clarify some articles..

not hard to understand just not ver clear on 240.5(B)(4)1

thanks again for the replies..

windy
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