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Beware "copper-clad aluminium" wire?


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I noticed a post on The Triumph Experience, that said that copper-clad aluminium "dominated" ads on Amazon for vehicle cables.      Sure enough, I looked on Amazon UK and found the same.  It seems that the cost of copper has made some suppliers to push the use of cheaper aluminium.

Replies on TE warned not to use this stuff!      It has been used in housing applications, with dreadful results as the aluminium microfractures.   Resistance rises, fires break out and this is a most unsuitable material for use in a car where vibration will cause that much more quickly!  A quick google for "copper-clad aluminium" found many sites with similar warnings.      Check before ordering that you aren't buying aluminium wiring.

John

Edited by JohnD
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Electromotive series (Pot Sod Cal Mag Alu Zin Iron Tin Lead Hyd Copper Merc ) means the alu corrrodes fast ! Likewise mercury thermometers are banned on aircraft.Its like sacrficial anodes on ships: the zinc corrodes , sparing the iron.

Peter

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Does the copper attack the aluminium, Peter?

I knew of the 'no mercury on aircraft' thing but until I saw this, I didn't know why:

 

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No mercury on aircraft is not quite right.

It can be moved but must be registered and packaged correctly.

During the 60' & 70' BEA transported quite a lot. Every now and then  rogue mercury or slap dash handling would allow a spillage.

It would be easily detected using radiography and then sucked up with copper sulphate and copper wire (If my memory is working)

Eventually one of our boffins made an electronic detector to find the little droplets - It worked well. 

There was very little trouble with Mercury as the insides of aircraft were usually very very oily & dirty and eventually coated in waxy product (Astrolan) and the mercury could not get at the Ali.

A more troublesome and quicker acting contaminate was Gallium - this would cut through the Ali with all the hairy stuff. 

When we X-rayed for this we looked for black spots - holes in the ali.

 

Roger

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Two different processes. The hairy stuff that John shows is aluminium oxide generated during the amalgamation process of mercury and aluminium. Mercury forms amalgams with various metals - the most familiar one being used for tooth fillings (Mercury/Silver/Tin/Zinc). This is not anything to do with electrolytic corrosion. 

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  • 4 weeks later...

No, just "CAT6 computing cable" isn't illuminating, I agree.  But still, I hunger for knowledge.   I had to look it up, and I know Wiki is frowned on but anyway:

Category 5 cable (Cat 5) is a twisted pair cable for computer networks. Since 2001, the variant commonly in use is the Category 5e specification (Cat 5e). The cable standard provides performance of up to 100 MHz and is suitable for most varieties of Ethernet over twisted pair up to 1000BASE-T (Gigabit Ethernet). Cat 5 is also used to carry other signals such as telephony and video.  This cable is commonly connected using punch-down blocks and modular connectors. Most Category 5 cables are unshielded, relying on the balanced line twisted pair design and differential signaling for noise rejection.

Category 6 cable (Cat 6), is a standardized twisted pair cable for Ethernet and other network physical layers that is backward compatible with the Category 5/5e and Category 3 cable standards.  Cat 6 has to meet more stringent specifications for crosstalk and system noise than Cat 5 and Cat 5e. The cable standard specifies performance of up to 250 MHz, compared to 100 MHz for Cat 5 and Cat 5e.[1]  Whereas Category 6 cable has a reduced maximum length of 55 metres (180 ft) when used for 10GBASE-T, Category 6A cable is characterized to 500 MHz and has improved alien crosstalk characteristics, allowing 10GBASE-T to be run for the same 100-metre (330 ft) maximum distance as previous Ethernet variants.

That's already more than I can understand, but makes clear your point, that neither CCA (!) nor CAT5e will do, in a CAT6 situation!

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