Mixing high & low voltage wires in electrical conduit?

[sleepdog]

Then if the OP is a banana picker in Guatemala the US NEC is probably not enforced in his jurisdiction. He can shove damn well anything through that conduit and hope for the best.

[Phil Munro]

We have to remember that some people have no idea how news browsers can be set -- that is, so that they do NOT display already read items. Also, other posts sometimes get between others and make it impossible to follow a thread without some context!

[blueman]

Actually, my situation is the reverse. I already have the low voltage alarm wires run in rigid metal conduit up the garage wall and across the ceiling to a centrally located heat sensor. I was hoping that maybe I could use that same conduit to also run cable for a ceiling light that I need to relocate. Of course, I could add a parallel run of conduit, but I was hoping to avoid the racecourse look of multiple conduit runs snaking across my ceiling (in my mind, one is more than enough visually :).

[blueman]

There is a difference between not knowing basic electrical code and wiring vs. not knowing a specific and rarely used detail such as in my question. I asked the question here to expand my knowledge and at least get some directional pointers to the right answer -- who knows, maybe my question has a simple and unanimously agreed upon answer or maybe it doesn't in which case I will need to look elsewhere...

Just as an anecdote, I recently hired licensed master electricians to rewire major portions of our house and I can assure you that they did not know details of the code outside of their daily work habits -- I am also pretty sure that they are not the book types that would be adept at skimming and interpreting the arcane details of code that they were not trained in. That does not mean that they are not capable of doing the wiring if informed of what is allowed.

[blueman]

So if I am reading the code English properly, what I am asking is not allowed even if the 110v (Class 1) wires are enclosed in Romex cabling unless there is some additional "barrier" between the power and alarm wires. Right?

[sleepdog]

I agree with you blueman, I was actually trying to help with my limited knowledge of using conduit and what I've read in the NEC about inductive heating, might be something you can look into and expand your knowledge of electrical. I hope you didn't mistake me for a real electrician and inadvertently burn your house down while reading my original response to your post. ;)

I wasn't seriously suggesting that you couldn't open a book. But I do think it is rediculous for individuals on usenet to tell others to keep their thoughts to themselves in a prevelently DIY forum. The free flow and exchange of ideas must not be impeded.

And I say that because I am now more knowledgeable of cabling requirements in conduit. I only had a part of the story with voltage issues and inductive heating. Perhaps you were not aware of inductive heating issues and therefore a mutual exhange may have occured.

Good luck with your project blueman

[SQLit]

Right on.

You will pay dearly for that stuff rated at 300 volts. Available, even at

600 volt insulation

By the way romex typically is not rated to be in conduit.

[Dan]

According to the NEC, you can only have signalling voltage and line voltage in the same enclosure if it's a listed assembly. (Furnace, air conditioner, etc.) Short answer, no!

Dan

[Jake]

This is not allowed. SQLit had the answer some time back... Romex does not belong in ANY conduit to begin with...

It is not required to be in conduit unless protecting it from physical damage, I would 'suppose' it would exceed the fill requirements of the conduit you are proposing to use, and it should not be mixed with low voltage or alarm signaling wiring because of the insulation rating differences.

Many alarm panels use semiconductor inputs, which sense either a opening or closing of a circuit. Placing the wiring within close proximity to other wiring can cause interference, and the alarm may either trip for no reason or fail to trip when it's needed.

There is no need to place your romex in conduit. If you must use conduit, use a separate one and THHN wire. You can also use flexible BX cable with the appropriate fittings.

Jake

[joe]

better off running separate conduit, eh.

[FDR]

Pull the alarm wires out of the conduit and run them alongside it. Then use the conduit for the power line.

[maradcliff]

[Doug Miller]

Wrong.

Not only does the NEC *permit* running romex in conduit, where needed for protection from physical damage the Code _explicitly_requires_ it.

[Doug Miller]

False. There is *nothing* in the NEC that prohibits running Romex in conduit.

[Tim Fischer]

Correct. He has asked for help here in this newsgroup. The fact that he's asking and not just cramming as many as he can in the conduit shows that he wants to do it right. Not everyone can/wants to understand the code books. On the other hand, if you're going to reply to his response, you should know what you're talking about.

Replies like "this should work" or "I don't think that would be a problem" are of little help when the code says Yes or No directly.

-Tim