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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Alarms, Phones, Aerials, CCTV & Datacomms >> Network cable https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1229037346 Message started by greg on Dec 11^th, 2008, 11:15pm

Title: Network cable
Post by greg on Dec 11^th, 2008, 11:15pm

Will unshielded Cat5 cable run in same boxed skirting as mains cables be OK so long as it maintains 50mm separation?

Thanks

Title: Re: Network cable
Post by Zambezi on Dec 12^th, 2008, 11:05am

I could be wrong but I thought it had to be separated by a partition of some sort if it was run in trunking. You could use Cat5 with higher rated insulation, not sure what it is called though.

Title: Re: Network cable
Post by CWatters on Dec 12^th, 2008, 9:18pm

I'm not sure what the regulations say about mixing low and high voltage cable, that's not my field but..

I would avoid running them just inches apart. I'd be happier with them more like a meter apart (say next joist bay over) and even then avoid very long parallel runs. If they must be run together go for CAT5 or 6 FTP which is a screened but quite a bit more expensive

To some extent it does depend on what you plan to send down the cable. Many people end up using their network cables for distributing analogue telephone, hifi or CCTV signals and they are more prone to interferrence than regular network traffic which has error correction upto a point.

Title: Re: Network cable
Post by londonman on Dec 15^th, 2008, 9:30pm

I don't see it as any big deal. After all, TCP/IP transmits and receives perfectly adequately via satellite...it is an error-correcting protocol after all...

50mm spacing ...now where did that figure come from? ...figure plucked from the air??? Why 50mm? Is the mains going to arc across any smaller gap? I don't think so.

Title: Re: Network cable
Post by Zambezi on Dec 16^th, 2008, 12:52am

Regs say min 50mm gap between band 1 and band 2 circuits, or all cables insulated to the highest rated cable in the bunch or if in trunking they should be separated by a barrier. Something along those lines anyway...

Title: Re: Network cable
Post by londonman on Dec 17^th, 2008, 9:57pm

wrote on Dec 16^th, 2008, 12:52am:

Just goes to show why many people ignore regs. If a reg is seen as sensible then people will follow and adopt it. Can anyone tell me why 50mm separation is needed. Sounds like someone somewhere stuck their finger up in the air when asked 'and what distance do you think they should be separated?'

Title: Re: Network cable
Post by Zambezi on Dec 17^th, 2008, 10:20pm

Somebody wearing a tie, thick glasses and a top pocket full of pens (who has never left the lab or worked in the real world) probably got paid a lot of money to figure that one out :-/

Title: Re: Network cable
Post by Twobarrows on Dec 31^st, 2008, 5:06am

Well the guy with glasses & pens may have known what he was talking about! It all depends on how signals are sent down the wires. If you have a +ve & -ve signal, interference occurs on both lines and cancels out. If however one is grounded & 'tother is signal it wouldn't!

Title: Re: Network cable
Post by plugwash on Jan 17^th, 2009, 2:14am

From an interference point of view running in the next compartment of a plastic trunking system is no different from running the same distance away with no barrier.

The rule in the regs is afaict more about preventing faults/damage from accidently putting mains onto ELV cables. It's probablly overkill with modern sheathed cables though (personally i'm surprised that you can't get cat5 with a mains rated sheath, it would seem very usefull for getting arround this).

Title: Re: Network cable
Post by Zambezi on Jan 17^th, 2009, 9:36pm

plugwash wrote on Jan 17^th, 2009, 2:14am:

I believe you can get network cable with mains rated sheath, never seen it but I believe it is out there.

This looks promising, they also do other types of cable....
http://www.csecables.com/data-cable/petrol-forecourt-cable.asp