Cat6 and power lines, how long is too long?

I'm running Cat6 through out the house and have all but one room done. Due to how the house is built I don't have access to the headers above three of the walls. I can access the same spot where the phone line drops, but this is about 4-5 inches away from the power line drop.

It's very tempting to just run the cat6 with the phone line and be done, but that would put it parallel to the power line for about 8 feet, separated by 4-5 inches. So far I've been able to avoid that in every other room.

Is that just asking for trouble with interference?

Eddie

Posted 2010-02-04T14:21:34.433

Reputation: 53

can you do that run with shielded cat-6? i assume you've used unshielded throughout the rest of the house. – quack quixote – 2010-02-04T14:26:12.657

Answers

Honestly, if you read every guide there is, they all say about interference with power lines and fluorescent light tubes. Whenever I do work for clients I always follow best practices and do this, however, (for myself) I have run power cables and Ethernet side by side a few times and never once seen a problem.

So, if you can avoid it - do. However, I have personally never had a problem, so if you are forced, you may want to try it just to see as you may not see any problems either.

William Hilsum

Posted 2010-02-04T14:21:34.433

Reputation: 111 572

+1 I ahve had exactly the same experience. Avoid where you can but I have had to run with power and over lights and not had issues. – Dave M – 2010-02-04T14:37:48.810

+1 for best practices. But you do what you have to do. – Sarge – 2010-02-04T14:40:10.957

Thanks, I might go ahead and make the connection and run a few tests to see what performance I'm getting and what the quality is.

Wiring a 30 year old house is gonna involve compromises. – Eddie – 2010-02-04T18:04:47.243

It is not just the interference you need to take into consideration.

I am a electrical engineer and it's mainly to do with regulation BS7671 (British Standard 7671 for Electrical Wiring). Which is segregation of different voltages 0 to 120v dc is classed as S.E.L.V OR Safe Extra Low Voltage. 55v AC and above is classed as low voltage also known as band 2. This is according to BS7671 appendix 7.4.2

Unfortunately the insulation on the cat 5 and cat 6 cable is not thick enough to take a belt from a main cable under fault load condition, Thus sending 240v at a high amps down your cat5 or 6 cable blowing your equipment and melting your cable.

So this is why it is advisable to run the data cable in a conduit or a separate trunking to protect the cable from both the electrical and interference.

Tony

Posted 2010-02-04T14:21:34.433

Reputation: 21