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DangerousDave
07-06-2005, 09:39 PM
Hey guys,
I'm just running some cat5e UTP cable through my house and its my luck that the only place in can go is next to a nice, juicy 240V power cable. It is running together for about 10m or so until it gets to where it needs to. Now my question, will this create interference (or much) that will kill the performance? I don't really care too much about the speed as it'll be running at 100mb, as long as most of the data gets there (well 2mb for you-know-what).

I've done a bit of googling and some guys in the UK seem to have no trouble with running them parallel, but then again who knows. Anyone here tested this, know of any problems?

Thanks,
David

godfather
07-06-2005, 09:56 PM
DEpends entirely on the type of 230v cable and the load in the cable.

EMI from mains is dependent on 230v cable type and the current carried.

Impossible to answer without those details.

Its not kosher to have these circuits in close proximity, from a Regulatory perspective unless the Cat 5e has double insulation.... but that is a separate issue.

DangerousDave
07-06-2005, 10:32 PM
It says 1080.1 TPC Cable 2.5mm core + earth, what ever that means! I just put the wires where they fit ;) Its just a cable coming from the fuse box into one of the rooms.
- David

pheonix
08-06-2005, 12:54 AM
That size cable is what they run to all your power outlets on the walls. It is not good practice to do what you want, either, as mentioned previously, because of the faint possibility of contact with the mains voltage via overheated cable or a wayward nail, or from the noise perspective.

If possible keep it at least 300mm away from the mains cable. Where practical of course. As for the interference angle, I shouldn't see that as a problem apart from when operating a device, using that mains cable, puts interference down the cable. Such things as arc welders and power tools.

Billy T
08-06-2005, 08:40 AM
If possible keep it at least 300mm away from the mains cable. Where practical of course. As for the interference angle, I shouldn't see that as a problem apart from when operating a device, using that mains cable, puts interference down the cable. Such things as arc welders and power tools.

It is switching transients that will corupt your data, and you don't need welders or power tools to create those. Running 10M in parallel is too long and too close for comfort. Induction effects don't just corrupt data, they can also damage your computer, in this case the cards at either end of the run.

Regulatory issues aside, your decision will depend on how important your data is, and how lucky you feel.

I wouldn't do it.

Cheers

Billy 8-{)

pctek
08-06-2005, 09:33 AM
Having done structured cabling for a living once I can tell you if that was done heads would roll.
You could install a wiring tray thing, I forget the proper name, run the cables through it...

pheonix
08-06-2005, 10:52 AM
This is a domestic dwelling, not a commercial enterprise so he can roll his own head. The cablers use wire-loop hangers now as tray is very expensive.

As for data corruption, thats the wonderful thing with tcp/ip, in that it will re-send the data. It is the standard over the Internet,and networkin, which encompasses satallite, and hence a lot more trouble from atmospherics than any domestic mains wire.

Now in an ideal world, we would take off the wall linings and drill new holes through the studs and dwangs, but I haven't met a house owner yet, who's willing to pay the extra. Or remove a roofing panel and drill down through the dwangs. Again most home owners will baulk at the extra cost. Mind you concrete tiles make this easy. Underneath the house is where it is normally run, except with concrete floors.

In the real world, sometimes an experienced judgement call is required, so standards cannot be strictly adhered to. I admit that your 10 metres is considered a "long" run with mains cable. As I have stated, you can minimise this risk by running the cable at least 300mm away from the mains run between stud holes.

It is really up to the original poster to make the choice, as he can see where it is able to be run, and what risk he is willing to take with the information posted.

DangerousDave
08-06-2005, 12:13 PM
hmmm, thanks for the info guy.

I'll try reduce the distance but I don't think I can do any better than 7 or so meters. Either way the plugs only have a computer and tv on the entire line, nothing like welders!

I'll just see what happens :)

- David

godfather
08-06-2005, 01:30 PM
TVs can create a large transient on turn-on. The instantaneous inrush current is very large and lasts only for a few milliseconds, but its quite a nasty load type in that respect.

techie
08-06-2005, 02:10 PM
Can you not go wireless?

SurferJoe46
08-06-2005, 03:41 PM
Dear Pheonix:

Please 'splain to an American what in the world a dwang is...as in your reply/post:

Now in an ideal world, we would take off the wall linings and drill new holes through the studs and dwangs, but I haven't met a house owner yet, who's willing to pay the extra. Or remove a roofing panel and drill down through the dwangs.

...as it is, I am not sure of your qualifying an ideal world that would allow such things in the walls of a human or even animal abode.

pheonix
08-06-2005, 04:04 PM
The construction of a wall in NZ consists of a top and bottom plate (usually 4" x 2" ) and vertical Studs holding them apart. To stop the studs bowing, "Dwangs" are placed between the studs. They are just horizontal 4x2 between studs.

I believe in the states they use plywood as bracing , over the whole frame, so wouldn't need those Dwangs.

A nice picture here (http://placemakers.co.nz/can-do/HangingDoors/framing_and_hanging_doors.htm)

SurferJoe46
08-06-2005, 04:09 PM
Over here we call them "FIRE BLOCKS", and OK, you can have them with my permission in the walls over there...but please "dwangs" is kinda close to the sound a finger makes in a fan blade. :p

Terry Porritt
08-06-2005, 04:49 PM
Also Joe, we have weatherboarding, you have sidings.

Graham L
08-06-2005, 05:01 PM
I don't think it will be too much of a problem, except for the regulatory aspects.

I don't think you're allowed to have the data and power sockets in the same flush box (unless they are separated by a proper earthed partition. I'm pretty sure you mustn't clip the mains and data cables together (unless the data cable has insulation rated for 230V use). There is probably a minmum spacing required.

50 Hz (or 100Hz) induced signals aren't going to bother the Ethernet (RF) signals at 10MHz and above. Switching transients, which might be a aproblem, are just that: transient. What's very bad is running Ethernet cables through fluorescent fittings. Fluorescent tubes are spark transmitters. :)

Murray P
08-06-2005, 05:45 PM
Dear Pheonix:

Please 'splain to an American what in the world a dwang is...as in your reply/post:

If you don't like the sound of the word dwang Joe, you can substitute the word nog or nogging which some in the less educated regions use.

Talking of running cables together, I was under a building the other week which had great masses of cat5 bundled together with 20mm entry mains, sub mains and tecoms cable draped over and around it (or visa versa). While the contact is only fleeting, it's shear lazyness in both running the stuff and not separating the entry/exit points.