Tuesday, August 22, 2006

Wiring Dilemma

Before the sublfooring in our attic conversion was installed, I used some of my newly acquired plumbing skills (and leftover pipe) to run a chase from what will be our "utility room" upstairs (one side of the low space behind the attic kneewall) all the way under our bedroom to the other side of the attic, behind the the other kneewall. The plan was to use this chase for wiring, such as cable TV, phone, etc.

Well this weekend during the Menards-17%-off-anything-in-a-bag-sale, I couldn't resist the temptation of topping off our bag with some Cat-5 (computer network) cable as well as cable TV (RG6 coax) cable. I already have tons of telephone cable (Cat-3) left behind at my employer's previous location, so I was all set to go.

I started running these three cable types in our attic last night - RG6 Coax, Cat-5, and Cat-3, but I paused halfway through the job with a question (plus it was 1:00 am); Will having these three different cables all bundled next to each other result in any signal bleeding or interference? What if I run audio speaker wires alongside too? Hmm.. time for some research.

8 comments:

Anonymous said...

I used to pull cable at AMD. I doubt you'll get any crosstalk. If you've never seen under a data center floor....its just...not pretty.

Anonymous said...

That's a good question. The short answer is it depends on the quality of the cable. If you have good CAT 5e, then you will have no problems, even with the speaker wire. The only place I can see a blead over problem is with the phone (CAT 3) into the computer network. There should be no troubles with the RG-6 or the speakers. Use good quality (Leviton or Hubble) RJ-45 connectors for your ethernet (computer) and you should be all set.

Anonymous said...

looking good j! about the wiring, think about bigger installations such as schools that have computer labs. They run a bunch of cat5e cables together in a cable tray and get no interference. considering you are only going to have a few cables, you shouldnt have a problem. most of the interference you can get is from power wires, not really from signal wires such as the ones you are using since they dont have enough magnetic field associated with them to cause any affect that you can notice. are you using 3/4" conduit?

glad the house is going well.
:o)

Anonymous said...

In the cat5 cable all the pairs are twisted to reduce crosstalk and inductance. I would skip running the cat3 and run an additional cat 5 for the phone wire. The RG6 is shielded and should not cause any interference issues. Do not pull romex through the same chase as that has the potential to cause interference in the cat5 lines. Good luck.

jay said...

Thanks all for the replies! You all make good points about cable traffic. Most of the run for these wires will all be outside of any conduit. There's only a small portion (12 feet) going under the floor through a 1.5" PVC 'conduit'. But I will certainly be careful about running alongside any AC power lines - I also found that crossing powerlines at right angles will result in minimal interference. Thanks again!

Poppy said...

updates???

jay said...

I ended up running coax, speaker wires, and CAT 5e alongside each other in some places, and alone in others. I also tried my best to keep the low-voltage wiring away from line-voltage wires (inside conduit), or if they had to be near each other, at least have them cross at right angles to minimize any cross talk. And so far, we haven't had any problems with data, video, or audio.

Luke20 said...

My situation is I made a navigation bypass button by interrupting the signal to the headunit from the parking brake and the speed sensor.

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