Safe Distance Between Phone Wiring and Power Breaker Panel?

[jaykchan]

I would like to know the minimum distance between phone wiring and the power breaker panel.

The phone line and the power line all come to my house through the same location. Currently the phone distribution block is just one feet away from the power breaker panel. Many phone lines are actually running parallel with power cables within inches away. So far, I haven't experienced any ill effect of the fact that the phone lines and power source are very close to each other. Having said that, I prefer to keep them separated, and I have the opportunity to do just that.

I am going to re-organize the phone distribution block for some other reasons, and I need to move the phone distribution block away anyway. I want to use this opportunity to keep the phone lines away from any power source. I am wondering what is the safe distance between a phone distribution block and a power breaker panel. Any idea?

Thanks.

Jay Chan

[Eric]

I believe that kind of info is in the NEC Code book. I dont have one handy but its worth having one, they are available in book stores. Eric

[Tony Hwang]

Hi, In my house they're all in the basement right next to each other. The breaker panel, phone terminal block, and cable TV cable splitter. Alarm logic box is installed right next to the other side of panel. Tony

[Greg]

They can't be in the same pipe, other than that it is not a problem.

60hz power and twisted pair does not "couple" that well, under any circumstances. It is mostly urban legend that power lines cause noise in communication circuits. The only thing you are really worried about is actually having them short together and put AC on the signal line. That is why they can't be in the same box or raceway.

[toller]

I had a phone company problem, but in trouble shooting he saw phone block was a mess (though not the problem) He was kind enough to tear it apart and rebuild it, about 6 inches from the circuit box. My phone reception is great.

[HaHaHa]

The distance they're at now is safe. What do you expect to happen, a bolt of electricity is going to "jump" out of the power circuits and into the phone line or something?

[e-mail]

[Pop]

The existing is fine; in fact, the phone wires can be run alongside metal sheathed or couduit, just not inside the same enclosures in any way, which is really to prevent shorting between phone/mains wiring. Being what's called twisted-pair, phone wiring is pretty much immune to inductive products from Mains wiring.

Where you might want to watch out is around floursecent ballasts; getting too close to those can sometimes induce hum because of the stronger magnetic fields (xfmr windings in the ballasts). A transformer is a lot more likely to induce into a phone line because of the wound shape; where Main wires are simple straight wires, comparatively. So if you do get a hum on the lines, suspect a xfmr with hight output voltages such as a flourescent light fixture first. Twisted-pair phone wires are inherently 'immune' to a lot of transference, but there is a limit when magnetic fields get close enough. Normal house wiring isn't much of a problem though. A couple or so inches is surely more than sufficient for wiring. Heck, I have mine wound around conduit in the basement to make it easy to keep it from sagging, and the lines are perfectly quiet. It's about 130' of wire from the demarc to my computer and it shows line noise here as zero. Makes for good modem connections .

Pop

Pop

[jaykchan]

Thanks for everyone who has replied.

Seem like phone wires can be placed close to power line without any problem as long as they are separated by a couple inches. This is good to know that. This means I don't need to move the existing phone wiring.

Also thanks for pointing out that the phone wiring need to be kept away from floursecent ballasts. I am sure mine doesn't have this problem because there are only three floursecent lighting fixtures in my house. I will double check just to be in the safe side.

My home networking wiring book recommends keeping wiring at least 8 inches from the power line. I probably got the impression of the need of separating phone wiring from power line from that book. Now, I read the book again; I have a feeling that it is actually referring to data network wiring, not phone wiring. Sorry for the misunderstanding. Thanks again.

Jay Chan