Cat5e Cable

[RichardS]

Whilst laying a new floor in my office, I had to move all my network stuff, firewall, servers, etc into the loft.

Well, I'm so impressed by the silence of the office (and I can't believe how much noise those little Sun Ultra 5's give off, even with replacement silent fans) that I'm going to keep them up there in the loft.

Only one things needs to happen - have to replace the long run of cat5 patch cable with permanent network installation - 2 or 3 runs of cat5, no problems.

Now, I know that this ought to be done in solid core cable, but can I get away with using stranded (I'd be able to use the rest to knock up a load of patch cables of exactly the correct length for each run)? Will it work in punch-down connections?

Sorry if this is a really stupid question, but the last time I did any data cabling it was 10base2 using coax and AMP taps....

[tony sayer]

In article , RichardS writes

You shouldn't use it but it more then likely will work, but perhaps not that reliably. Still CAT 5 cable is peanuts cheap why not use the right stuff?.

Have you thought about temperature rise in the summer for you poor old servers!...

[Andy Hall]

It doesn't seem to work very well, IME, Richard.

I tried it once using good quality punch down blocks (Krone), and the connections weren't good, so I think it makes sense to get the proper stuff.

On another point, if you're going to put the equipment in the roof, you may have a problem in the summer. Temperatures can easily exceed

40 degrees which may cause unacceptably high temperatures inside the equipment. I've done this but built a cabinet to house the active equipment. This has intake and extract fans to the exterior of the house which are speed controlled according to temperature inside the cabinet. A thermostat would have been another way to do it.

[Andy Burns]

You can buy stranded patch leads up to 10m so you'd be unlucky if it didn't work at longer lengths than that.

I don't think punch down connectors will work reliably with stranded cable.

What about bee-sting clamps ;-)

[Grunff]

It won't work reliably, no. As you punch down stranded, the strands compress, and you don't get anywhere near as good a connection as you would with solid core.

If you really want to do it with stranded, terminate the ends with RJ45s.

[RichardS]

OK, thanks, Tony, Andy & Andy

I'm convinced, solid core it is. I know it's cheap as chips, but wanted to use up the remainder for patch cabling - guess it's just the Yorkshireman coming out in me! I'll get both & blow the £18 or whatever... :)

yup, temperature is a concern. If it proves problematic, I'll move things back downstairs temporarily for the 2 month's peak summer temperatures. Who knows - perhaps I'll even insulate the roof properly in the next couple of months!!!

[Lurch]

On Sun, 28 Nov 2004 22:35:41 -0000, "RichardS" strung together this:

Yes it will work, I've used both types of cable for the wrong application for temporary services [read: nearer permanent!] and haven't had any problems. For the price of a box of cheap cat5e cable I'd do it properly though.

[Tim S]

Hi

You might want to make sure you get Cat5e (like your subject says) not Cat5. Same stuff, physically, but the Cat5e has been tested and proved to higher standards, so you'll be good for a gigabit/sec. Not that your Sun

5's are ;->

Cheers

Timbo

[RichardS]

yup, already clocked that - roll of cat5e solid core to be delivered tomorrow morning, along with faceplates, punchdown tool, etc.... should keep me busy for a couple of hours!

Oi, that's fighting talk - that little box is running 2 Domino 6.5 partitions simultaneously for our dev environment, and stays alive and stable for months on end.... it just shouldn't be possible! Mind you, gigabit to it would be something akin to replacing your front drive with a dual carriageway....

[Tim S]

He he.

Yes - I don't doubt it - Solaris on Sparc 5's was solid. Not fast. But solid. Even more than linux, and that's better than Winblows by a long shot.

I'll get me coat...

Timbo

PS Good luck with your wiring.

[Stefek Zaba]

If you're not going to be moving the patchcords much, you can appease your save-a-penny instincts by using the solid stuff to make up somewhat inflexible patch cords; it's even possible to get RJ45 plugs which are designed for solid rather'n normal stranded cable.

But it may be easier to pick up 10m or longer preloved stranded patchcords doing a Medusa impression in a cardboard box somewhere in the corner of a server room ;-) The extra attenuation of stranded vs solid won't really hurt you at 10 or 20m lengths...

Stefek

[tony sayer]

Attenuation?, how do they differ then?....

[Stefek Zaba]

The stranded has higher DC resistance for one thing; I'm not sufficiently literate in signal propagation to opine reliably whether there are other effects at the 100MHz or so signalling frequencies. Hence the use of solid-core for the fixed-in-the-building wiring, but the more handleable stranded for patchcords.

The specs have a fair bit of headroom to maintain reliable working up to the 100m inter-station limit, in the face of reasonably foreseeable interference from other cables and "normal" electrical kit (i.e.: aircon units switching in and out a couple of feet away - reasonable; Dingley with his 200A welder right behind the patch panel - cruel and unusual ;-). Hence it being possible to get away with violating individual aspects of cautious best practice...

HTH - Stefek

[John Weston]

(f.u. quote not quite correct but...)

Don't do it (use solid core for patch wires terminated in plugs)... The pins in the plugs you'd use for the patch cables are designed to pierce the insulation and then go into STRANDED cable. If you use them on SOLID core cable then the pins will not go in far enough or get deflected by the core so will probably make intermittent contact with either the core or with the socket. I've seen sockets shorting adjacent pins due to the crimp not pushing down the contact far enough and the pins being proud of the inter-pin barriers.

Same with telephone type plugs. The plugs must be on stranded cable.

[Rob Morley]

Unless you use plugs that are intended for use with solid cable, of course.

[tony sayer]

There are ones designed for solid core cables and I've use a few in me time but these days I cant be arseed to make them anymore, when their sooo cheap!...

[tony sayer]

Usually at higher frequencies things like skin effect come into play for stranded cable can have its advantages.

Mind you , you'd think fibre would be much cheaper by now;)

Yes we have C5 cables where they didn't oughta. Lot going for the balanced working nature of C5:)

[The Natural Philosopher]

I think that s more a cist iissue really, and reliability. Solid core is fine if it doesn't get moved, and cheaper to make.

There is very little difference RF wise beween solid and stranded wire.

Stranded is, I think, if anything, better.

The 100m limit is not attentuation bound, its time delay bound for ethernet.

If you put a (suitable) switch at each end, you can get reliable operation at up to a few kilometers at 1Mbps. As ADSL shows.

I've certianly seen 500m or so at 10Mpbs, although for more than that one tends to start using DSL technology rather than ethernet switches.

[Simon Barr]

I've made up hundreds of leads using solid core cable over the years with no problems at all. Maybe the odd plug doesn't crimp properly first time, but another squeeze and its OK.

I now have an AMP crimp tool but in the past used to use a cheap twenty quid one with no problems.

[John Weston]

Me too, but why run the risk of having to re-crimp and/or have the pins bend, since the costs of ready-made patch cables are so low for home use? Even when making your own, for volume situations, you're better getting some correct stranded cable so you don't have future problems due to the flexing patch cables can get. Don't forget that the crimp is often not correctly made to solid cable with ordinary stranded-type plugs and can work loose if subject to movement.

Re another post -

If you have an electrically harsh environment, use fully screened CAT5 cable (Shielded Twisted Pair(STP)rather than Unshielded Twisted Pair(UTP)). Also use screened connectors to terminate it to maintain the integrity of the shield. See

as an example - it's cat6 rather than cat5 but you can see the principle.