Be careful buying Cat5e cable

[Andrew Gabriel]

Increasing amounts of Cat5e cable is appearing on the market which is actually copper covered aluminium conductors (CCA). This does not conform to the specs required for high speed networking cable. When you buy Cat5e cable for networking, make sure it's solid copper, and not CCA. Some large new building installations have had to be completely ripped out and replaced, after the contractors thought they'd got a good deal on the cable, too good as it turned out.

[DA]

I would be very interested to hear the particulars of this case. Was it a cable sold as a brand or did they know they were getting something sub-par, just not how bad it is?

I imagine you are describing a project with only the cable pulled, not a complete installation? The difference in conductors would be rather obvious once they started punching it down.

Have they literally removed or laid new cable ontop?

[NT]

cable sold as a brand or did they know they were getting something sub-par= , just not how bad it is?

complete installation? The difference in conductors would be rather obvious= =A0once they started punching it down.

AFAIK using CCA would only increase resistance marginally. Presumably there are other issues with it that result in it not meeting spec.

NT

[DA]

I would think it's probably more of the conductor not staying put in the IDC connectors kind of issue. Does anyone have some experience with punching down CCA telecom cables (regardless of category spec)?

[Part Timer]

Have you actually got hold of any? I think I may have some here, having looked at the cut ends with a hand lens, and the outer jacket is quite loose. Came from eBay seller safekom as a 50m length complete with a handful of RJ45 plugs and boots for £7.95 delivered. I did a single run between 2 wall sockets on 2 floors of the house. Seems to work OK for sending files to my laser printer via a 10/100 switch. Probably have half of it left over - what are the actual practical consequences?

[fred]

In article , Andrew Gabriel writes

Good reminder.

Let's not forget good old CCS too, only suitable for use as concrete reinforcement or as a cable routing snake.

You remind me to post an update to the toolstation CCS telephone cable fiasco which ended with them withdrawing pure copper CW1308 cable from sale altogether rather than fix their apparent bulk purchasing mistake.

[Andrew Gabriel]

cable sold as a brand or did they know they were getting something sub-par, just not how bad it is?

complete installation? The difference in conductors would be rather obvious once they started punching it down.

I can't tell you about the one I knew about, but a google search turns up this

100 boxes of cable had to be removed from the installation. Looks like Cat6 is also impacted.

I came across this because I needed a new box of cable, and CPC had some which was significantly cheaper than the rest, and I was trying to work out why, when I noticed the CCS, and then searched further, and someone knew of a customer who was recently hit by this.

I had also just bought some outdoor Cat5e which was going cheap. Fortunately it looks like this is solid copper, but I'll check when I next get access to it again.

[Andrew Gabriel]

Short lengths running at 10/100 are unlikely to be a problem.

100m running at 1Gbit might be. Life of connections might also be impacted.

[NT]

Soldering after punching would solve that, if you ensure the soldered joints cant be moved.

NT

[John Rumm]

Sounds like a way to end up with one molten plastic mess! Not to mention some cat5 has a hard PTFE style of insulation that you really don't want to go melting.

[Bill Wright]

Very interesting. Similar situation has existed for years with TV cable. The expression 'CT100' appears on drums of imported cable that is nothing like proper CT100, and performs very badly, especially at the top end of the satellite IF band. This has caused a lot of grief when long runs have been put in by the electricians, only for the TV system installers to condemn it.

Bill

[John Rumm]

Indeed, I have been careful to avoid it so far... basically if the 1000' box is less than about £70 at the moment, then look at what you are buying very carefully.

(there is also some Copper Clad Steel (CCS) out there)

Various reports suggest it can sometimes work ok with regards data speed, but is less robust when pulling, more likely to fail later due to corrosion, and is not as good when used for PoE applications.

Some related technical details here:

[dennis]

BT have and they won't make that mistake again. Its fine for the first few years. Then it starts to fall apart. It appears that even road traffic vibrations can harden the cable at the joints and then they snap. Maintenance makes it worse, fix one break a few more.

[NT]

Heh, I do think stripping the ends come into it somewhere :)

NT

[Dave Liquorice]

Yep, our line is ali when ever I see a BT man down a hole along the route the line takes I keep a very careful eye on ours remaining serviceable. Factures in the IDC jelly bean and the jelly/uncut insulation can sometimes mean the wire doesn't drop out making it obvious.

[geoff]

In message , DA writes

Paging Wppltd ...

[geoff]

Not on punch down connectors it doesn't

[John Rumm]

That really sounds like a non starter for thin wire applications like these. The whole point of using IDC punchdown terminations is that they are very fast and easy to do "in the field". If you needed to tit about stripping insulation and soldering then you would add so much time and inconvenience to the job as to render it impractical for all but a trivial number of terminations. (remember that even installing just one network socket with a pair of RJ45s requires 32 terminations).

[Andy Wade]

And mains power cables:

[NT]

Stripping the ends is only a few seconds each conductor. Single network sockets are 8 terminations at each end. I'm not saying go and buy cca/ccs, but if you've already got it installed its workable.

NT