CCA and CCS cables

[Stephen]

Hello,

I must admit that until I read here, I never knew these existed or what they meant (copper coated aluminium, copper coated steel). I made the mistake of buying some cable from cpc, either not seeing or not understanding the three tiny letters at the end of the description.

Is there ever a time when using CCA or CCS is as good as or better than using solid copper. I ask because I have found out after the event, that my bell wire for my doorbell is CC something.

I am looking to buy some telephone cable to run a socket upstairs and Tool station sell two varieties; you've guess it: one is CCA and the other is CCS.

Perhaps I'm just being a copper snob but I'd like my cables to be copper through and through.

Is there a reason for this? Is it a coincidence that these cables are both small strand sizes and are not copper?

Thanks, Stephen.

[Mike Tomlinson]

En el artículo , Stephen escribió:

It's fine for things like doorbells and phone extensions.

It's only really desirable for data transmission (Ethernet installations, for example.) You do want 100% copper for that.

If you buy a reel to fix your doorbell, you may as well go for 100% copper. Any cable you have left over can then be used for Ethernet installation.

Cost. There should be little difference nowadays because the cost of copper has plummeted. If a stockist still shows a large price margin between CCA/CCS and solid copper, it's because they bought stock when the price of copper was high and are unwilling or unable to absorb the difference.

Also watch that the cable is usually sold in 100m and 300m lengths - make sure you're comparing like-for-like.

Yes. The strand size doesn't matter, what does matter are the characteristic impedance and capacitance of the able, plus the number of twists. This is defined in the Cat5 / Cat5e / Cat 6 / Cat 6a cable spec.

CCA and CCS are more brittle than pure copper, and more prone to fracturing if handled roughly during installation. This can lead to frustratingly intermittent faults. They are completely unsuitable for making up patch leads.

[John Rumm]

It depends on what you are doing with it... the general answer to the question is "no", but how much worse it will be varies with application. With a doorbell its likely to work fine. You may get less reliability with age, but that is debatable.

So order elsewhere.

For datacomms applications, its doubtful if many of the CCA or CCS cables even meet the required standards to be CAT5e etc. So you are wise to be wary. Also for any flexible cable application (especially at small cross sections) they will prove less durable.

[Syd Rumpo]

Thin strand CCS makes impressive showers of sparks. Wire a couple of inches into a bayonet connector and put in place of a mains bulb.

Of course it's unsafe, a shock hazard, a fire risk etc. But it's fun.

Cheers

[tabbypurr]

They're cheaper, but CCA is liable to fracture if bent repeatedly. CCS is much stronger, hence is used outdoors for phone wiring. Either is fine for bell wiring, but if there's any possibility of putting broadband down phone wiring then avoid CCA/CCS.

NT

[dennis]

CCA gets its reputation for being unreliable because BT used it. It gets a lot of rough handling in the CAB and breaks. In a normal household where the cable isn't moved about a lot it should be fine. CCS probably gets its reputation from the same place but I don't know of BT using it.

[spuorgelgoog]

CCA or CCS do not comply with Category 5 / 5e data cable standards, or BT CW1308 internal premises cable standards. Those standards specify copper.

The strand size, and hardness, is fairly critical as all these use IDC connections and rely on the core - to - connector blade interface to make a secure connection.

Owain

[Andrew Gabriel]

Problem in outdoor cabinets was corrosion, not handling. They had to stuff the cabinets full of dessicant bags to keep them working at all, until it was eventually stripped out.

There are 3 steel wires in the standard 2-pair BT drop cable, but they aren't used as conductors, only for extra strength. The wires used as conductors are copper. Hence 7 wires in total.

[tabbypurr]

With respect CCA got its reputation long before BT existed. Ferrous electrical wire has a much older history.

NT

[Johnny B Good]

====snip====

AFAICR, those 3 steel wires were known as the "catenary" wires.

[Dave Liquorice]

better

When the totally overwhelming factor is capital cost. Costs due to poor performance of anything using it or maintenance excluded. It'll be OK for a doorbell (provided it doesn't get wet/damp) and for a short, telephone only, extension but anything dataery, ADSL, VDSL, Ethernet, etc forget it, copper is reuired.

That's what happens here, engineer opens joint post or bullet to trace/fix a line. The movement even gentle, I've watched 'em, breaks

3 other lines, which is fine if the wire falls out of the jelly bean, engineer normally spots stray wire and lonely jelley bean and remakes the connection. Trouble is the wire can break but not fall out. Engineer fixes orginal fault but someone elses line is now dead, they report a fault, so engineer comes out and ... rinse and repeat. Normally takes a week to two weeks for things to settle down. Another thing that can happen is that the a wire doen't break completely so POTS still works but the discontinuity upsets ADSL and makes the upload a bit iffy, overall less stable and a bit slower. Our line is currently in that state, waiting for an engineer to give it a fatal prod.

Cabinets still have dessicant bags and there is still Ali in service. I'm in two minds about them stripping out the Ali as what we have is one of the heaviest ali cables they used, each wire is 0.75 mm dia noticeably larger than the copper. But of course ali has higher losses ...

These days if they go to the expense of stripping out the direct buried Ali they ought to replace it with FTTP. B-)

[dennis]

OK, Post Office then.

[John Jackson]

It normally happens the other way, it's the POTS that fails because it needs DC continuity but the ADSL that keeps working because it doesn't.

[Dave Liquorice]

Read what I wrote, one of the wires *doen't* (sic) break.

The DC loop still works so POTS does but the raised resistance at the near break upsets the balance of the line and I find makes the frequencies used for the upper end of the upload and lower end of the download bands less able to carry as much data.

[Vir Campestris]

It's also rather prone to corrosion damage.

Andy

[John Jackson]

I already did that thanks.

You actually said

one of the wires *doen't* break COMPLETELY.

Not when you get what the industry calls an HR joint, high resistance.

No it doesn't with an HR joint.

ADSL doesn't care because even with a full break it often still works fine as long as the pieces of metal are still close to each other.

It doesn't work like that as a complete break in the DC path shows.

[Mike Tomlinson]

En el artículo , Dave Liquorice escribió:

You're wasting your time arguing with one of the nyms of the troll Rod Speed. Usenet is write-only for him, he's not going to read anything you write.

"" "John James" "Simon Brown" "Jacko" "Simon263" "John Chance" "Ratsack" "Hank" "kshy" "JHY" "Blano" "Santo Brown" "hqhy" "Jim Thomas" "Sam Thatch" "Hanny Z" "78lp" "John Jackson"

[Stephen]

Thanks for all the replies.

I would have thought that all phone wires would carry broadband these days, so I am surprised there is a market for CC?-type wires.

I have been looking on CPC and they seem to sell quite a range. Some are 0.2mm^2 CSA up to 0.5mm^2 CSA. Is bigger better?

The 0.5mm^2 cable says it meets BT specification CW1308, whatever that is. The thinner cables do not.

Interestingly they say only for internal use; I thought the black version would be ok for outside? Not to worry, I only want to use it inside anyway.

Thanks, Stephen.

[Dave Liquorice]

Meh. Can't be arsed to carry on with anyone who doesn't accept what another says about their own direct experience.

[Dave Liquorice]

Cost...

Within limits bigger the better and it really ought to meet CW1308 which is the defined standard for (internal?) phone wireing cable. Smaller stuff might not work well/reliably with IDC connections and mixing wire sizes in the same IDC is asking for trouble.