Netrual wire

[cdb277]

Common sense tells me this not a good idea but after looking through the code book I cant find a specific reason:

My company is installing linear fluorescent light fixtures in a warehouse and we are using 208 volt circuits to feed the multi tap ballasts. My foreman called earlier and asked if he could run neutral conductor straight through each light until he comes to a door location where he needs to install a exit sign. At this point he would pull off one leg of the 208 circuit and use the neutral conductor as a 120 volt circuit for the exit sign. Now I have to admit I don't like anything about this idea but can someone please explain to me, or better yet reference me, where this is illegal in code?

 

[charlie b]

I see nothing in your description that would comprise a code violation. It is not such a good idea from a design (and in particular a maintenance) perspective, as you would have to turn off a lot of lights in order to service a single exit sign. But otherwise I don't see anything dangerous here.

 

[JFletcher]

would splitting off one phase of the 3ph 208V (120V) and using the grounding conductor for an exit sign violate 300.3(B)?

eta: as CharlieB mentioned,this would be a maintenance nightmare... having to kill a row (or several) of lighting to change out a bad exit sign/e-light. If all your exit signs/elights were on one/two circuits of their own, simply killing the breaker(s) would be a fast way to tel if the battery back ups were workings... an if they werent, no biggie to secure power to just them to change them out w/o killing lights to a fair portion of the warehouse.

 

[iwire]

would splitting off one phase of the 3ph 208V (120V) and using the grounding conductor for an exit sign violate 300.3(B)?

It could but if done correctly no.

 

[ActionDave]

would splitting off one phase of the 3ph 208V (120V) and using the grounding conductor for an exit sign violate 300.3(B)?

eta: as CharlieB mentioned,this would be a maintenance nightmare... having to kill a row (or several) of lighting to change out a bad exit sign/e-light. If all your exit signs/elights were on one/two circuits of their own, simply killing the breaker(s) would be a fast way to tel if the battery back ups were workings... an if they werent, no biggie to secure power to just them to change them out w/o killing lights to a fair portion of the warehouse.

It's not a code violation. It's not a maintenance nightmare. It's often an efficient way to get power across a building.

I see no problem with the idea. Modern Exit signs are capable of handling multiple voltages, so if the OP hooks them up 208V it's no different from a maintenance standpoint.

I do wonder why the OP wants to use 120V for the signs.

 

[iwire]

I do wonder why the OP wants to use 120V for the signs.

The exits I get are 120 or 277 via a black lead or orange lead, no option to run them on 208.

 

[ActionDave]

The exits I get are 120 or 277 via a black lead or orange lead, no option to run them on 208.

Now you are going to make me wonder about this all night. Most anything I have hooked up with a ballast in the last five years at least is universal voltage 120-277. Come to think of it that has not included many Exit signs.

At any rate if it is true that there is no 208V option I don't see anything wrong with pulling a neutral and tapping off of one leg of the light circuit.

 

[Little Bill]

If the worry is a maintenance "night mare", just run the neutral & 120V leg into a switch.
You could use either a single pole or 2-p switch. That way if the sign needs work all you have to do is turn off the switch!

 

[wallyworld]

Use a lighting fixture disconnect at Exit sign.

http://www.warehouse-lighting.com/s...uzLW9c__oqjl01a0qgBUv2jCGn8gce7OKfhoCBwrw_wcB