Is it legal to use a 2P 480v snap switch to control lighting?

[Steve-R]

Is there anything in the NEC that would prohibit the use of a 2P 480v wall snap switch to control HID lighting? I have been looking at NEC 2008 404.8 (B) & (C), which require barriers between separate devices if above 300v, but not for a single device. Is there anything wrong with what I'm proposing?

Someone is telling me this is not allowed. I don't have a code reference from them yet.

Also, can anyone point me to a cut sheet for a 2P 480v switch, or a model number? I'm having trouble finding one.

Thanks for the help.

 

[iwire]

There is no NEC rule prohibiting it that I am aware of.

That said I doubt you will find a 480 volt rated snap switch that looks like a typical light switch and fits in a single gand device box.

I suggest a small two pole contractor with a 277 volt coil and a single pole 277 volt snap switch to control it.

Heck you might even find a RIB (relay in a box) that could do the job.

 

[Steve-R]

I found this Q/A article, which appears to me to make a good case for NOT using a 2P switch to control 480v lighting. The article is from 1999, so it is pretty old. Perhaps UL has modified guide card category WJQR on "snap switches"?

Any thoughts would be appreciated:

http://ecmweb.com/mag/electric_code_quandaries_26/

Q. What is the NEC ruling on using a DPST switch to control a 277V light and a 120V fan?

A. There isn't any objection in the NEC itself to doing this, because Sec. 380-8 (b) only applies to adjacent devices. However, Sec. 110-3(b) effectively incorporates by reference all restrictions in the UL guide card data. In this case, you'll find the following information (in guide card category WJQR on "snap switches") "Multipole, General Use Snap Switches have not been investigated for more than single circuit operation unless marked '2-circuit' or '3-circuit.'"

Some of us have been trying for many years to interest manufacturers in securing such listings on some of their double- and triple-pole switches with absolutely no success. To the best of my knowledge, there are no snap switches with the applicable listing. In fact, there don't appear to even be listings for two 120V circuits, such as might be applied to two oil burners. Even though the two-pole switch you'd like to use for that application is rated 240V, this eliminates any issue about potential between adjacent energized parts running above the nominal voltage rating.

 

[Steve-R]

There is no NEC rule prohibiting it that I am aware of.

That said I doubt you will find a 480 volt rated snap switch that looks like a typical light switch and fits in a single gand device box.

I suggest a small two pole contractor with a 277 volt coil and a single pole 277 volt snap switch to control it.

Heck you might even find a RIB (relay in a box) that could do the job.

A contactor was my first thought. Thanks for the input.

 

[weressl]

There is no NEC rule prohibiting it that I am aware of.

That said I doubt you will find a 480 volt rated snap switch that looks like a typical light switch and fits in a single gand device box.

I suggest a small two pole contractor with a 277 volt coil and a single pole 277 volt snap switch to control it.

Heck you might even find a RIB (relay in a box) that could do the job.

Here you go: http://www.maraindustrial.com/servlet/the-29/Legrand-30A-240-dsh-500V-Switch/Detail

 

[iwire]

Here you go: http://www.maraindustrial.com/servlet/the-29/Legrand-30A-240-dsh-500V-Switch/Detail

Well no kidding, a manual motor starter, never seen one of those :wink: ..... In ivory or white or with a handle the dimensions of a light switch:grin:

I doubt you will find a 480 volt rated snap switch that looks like a typical light switch

And your a better man then I if you can get that device in a single gang device box without ground faults.

fits in a single gang device box

I assumed, which is always a risk that the OP was looking for typical looking light switch.

But I do agree with you, that style manual motor starter would work.

 

[iwire]

I found this Q/A article, which appears to me to make a good case for NOT using a 2P switch to control 480v lighting. The article is from 1999, so it is pretty old. Perhaps UL has modified guide card category WJQR on "snap switches"?

Any thoughts would be appreciated:

I don't see the relevance of that link to your questions.

That link is about using a double pole to control separate circuits, you would be controlling one circuit unless I misunderstood your installation. :smile:

 

[roger]

I found this Q/A article, which appears to me to make a good case for NOT using a 2P switch to control 480v lighting. The article is from 1999, so it is pretty old. Perhaps UL has modified guide card category WJQR on "snap switches"?

Any thoughts would be appreciated:

http://ecmweb.com/mag/electric_code_quandaries_26/

This is not the same thing as operating a single circuit from a double pole switch.

Roger