I live in Queens, NY and my house is currently being wired for voice and data.  As my contractor is trying to run these wires far away from the electrical wiring, he stumbled across a problem.  On room is over a concrete slab with one conduit pipe going into it from the main house.  All the electric (BX cable - 3 wire enclosed in a flexible metal jacket)runs throught this wiring.  Without breaking the walls of the room open, can he run my voice, data, and cable lines through this conduit pipe?  As the pipe runs up and over a waste pipe, the length is about 8 feet.  I know data and voice can cross electric wiring at 90 degrees, but can it run parallel for 8 feet??

It won't be a problem as far as interference is concerned, BUT even though the electrical is armoured BX, will the inspectors sign off on low voltage and electrical running in the same conduit?

Thanks TTT!
Do you think it is not a problem because the BX is armoured or because of the relatively short distance of 8 feet.  As for inspection, the house was wired months ago for electric and was already inspected.  My contractor began wiring the house for data and voice just recently.  I'm not sure if the data and voice need inspection??

"Do you think it is not a problem because the BX is armoured or because of the relatively short distance of 8 feet."

Yes, and yes.

"I'm not sure if the data and voice need inspection??"

Depends on where you are located, and "The Authority Having Jurisdiction". Here in California, low voltage (91 volts or less) does not need inspection, however you must follow codes like fire stopping, pleneum ceilings, etc. I don't think any inspector would sign off on mixing the BX cable and Cat-5 through the same sleeve like you propose, but -HEY- its gonna work...although you wouldn't catch me doing it personally.

It should be okay. Even though it is not the perfect scenario, with BX installed it would be no different than how some modular furniture is fed.

Steve
tele-dataservices.com

most furniture ive seen has a seperate chase to keep 110v and cat5 seperate. Have you considered using sheilded cat 5 for this drop? The armored cable should block the EMI's from affecting the data but i wouldnt do it this way unless i had too.

The cat5 cable being used is Cat5E Riser cable made by Commandlink.  I believe my contractor bought it at Home Depot.  It comes in a grey cable jacket, but I don't know its insulation properties.  Is this Home Depot stuff insulated adequately?  Should a buy a skinny raceway and try to pull it though the conduit to (hopefully) further insulate the cat5?  

The good news is that BX power cable is twisted, not nearly as much as UTP (CAT5) but this twist reduces the EMI from the power circuit.

My understanding of the NEC allows for your install as well.  If I understand your situation correctly then the conduit in question is not technically a conduit, but rather a sleeve.  The BX itself is a mechanically protected branch circuit which runs in this sleeve.

You are correct ve3slw.
The word conduit was probably the wrong choice for this application.  The BX cable, cat5, cat3, and cable tv all run through a 3 inch diameter pipe running through an exterior wall to an addition set on a concrete slab.

I would like to thank everyone who responded to my posting.  Just last night I helped run the data, voice and tv cables through a raceway and then through the pipe I mentioned above.  I will not be able to test anything until I get further into my house project, but I feel more confident in this setup because of all of your advice.  Thanks again!

I have understood the issue as needing a physical barrier between high and low, same chase just don't let them touch.  A short piece of innerduct or the like will satisfy.

Why is there never a phone in any of the phone closets?