# Run 120V, CAT3 and RG6 together????



## mtplus (Jun 22, 2006)

I need to run 3 wires in a room: 120V (12/2NMB), telephone wire (CAT3), and Cable TV (RG6). Which of these wires, if any, can I run together (through the same hole) through the wall studs.

I could not find this answer in the NEC, so if you have a NEC reference, that would be appreciated as well.

Regards,

Robert


----------



## [email protected]&R (Jul 26, 2005)

120 needs to be seperated from the other 2. The high voltage magntic field will mess the low voltage signal up. I believe its a minium of 2" spacing between them. I normally have about 6" between them though.

I personally never run cat3 I always use at least cat5e so it can be upgraded later if needed and dosent cost much more.


----------



## mdshunk (Mar 13, 2005)

I don't run Cat3 anymore either. It's actually more expensive at my supply house now, because Cat5e is so very popular. 

In any event, the NEC does not concern itself with RF performance of cables. The code is only for safety, and there is no safety issue with running your low voltage cables through the same bored holes with line voltage.

That said, there are some performance issues that need to be considered. For those, you need to look and BICSI and TIA/EIA standards. These are standards only, and do not have the force of law. They will need to be followed if a print note calls for these standards to be observed.

Long story short, BICSI standards call for your Category 3 and 5 cables, and your Series 6 cables to be run 12" from line voltage where run parallel, and 3" from line voltage where they cross perpendicular.

Your Cat3 and 5 cables can be run through the same bored hole with other low voltage stuff like the Series 6 cable and any alarm or speaker cables. 

Best of luck.


----------



## [email protected]&R (Jul 26, 2005)

mdshunk said:


> I don't run Cat3 anymore either. It's actually more expensive at my supply house now, because Cat5e is so very popular.
> 
> In any event, the NEC does not concern itself with RF performance of cables. The code is only for safety, and there is no safety issue with running your low voltage cables through the same bored holes with line voltage.
> 
> ...


Ahh I was told 2" from power running in parallel when I went to cisco network training about 6 years ago now. I was also told thats far enough so the magnitic field around the 120 would not reach the low voltage and screw with the signal. I guess this was a change made since I finished the course. Or was I just told wrong by the teacher from the start? Glad to know I need to change the way I been doing it then.


----------



## giddonah (Mar 3, 2005)

Actually, the Cisco Networking manual says 18" when parallel.


----------



## mdshunk (Mar 13, 2005)

Realistically, in a dwelling, you can run cabling however it pleases you and the domestic user will likely notice no performance issues. I try to adhere to the BICSI standards, which is the most accepted of standards. I've seen some pretty hairy cable installs in commercial applications that I sure wouldn't have been proud of, but it seems to work fine for them. If this was mission critical stuff, you'd want to go by the reccomendations of the networking equipment (Cisco, for instance) to be sure that the high dollar equipment will work well. I've only done two jobs where the cabling had to be "certified", and even then cabling that was installed to the letter, a few runs needed replaced. 

I half think it's all a marketing thing.


----------

