copper coated aluminum wire

Shadowcatcher

I was thinking of using some 8ga copper coated aluminum wire for some AC application in our Teardrop trailer. Now the back story I picked up some Harbor Freight jumper cables very, flexible copper coated aluminum to make up a tow vehicle jumper to trailer battery, charge when the sun is not enough, cable. I soldered well and is flexible. My understanding is that there is a skin effect using this sort of wire.
I need to rewire the main shore power connection which is currently 10ga solid copper which was put in before the water heater and cook top and...
Using the more flexible 8Ga would be much easier with the more flexible 8ga.

inetdog

Re: copper coated aluminum wire

Shadowcatcher wrote: »

I was thinking of using some 8ga copper coated aluminum wire for some AC application in our Teardrop trailer. Now the back story I picked up some Harbor Freight jumper cables very, flexible copper coated aluminum to make up a tow vehicle jumper to trailer battery, charge when the sun is not enough, cable. I soldered well and is flexible. My understanding is that there is a skin effect using this sort of wire.
I need to rewire the main shore power connection which is currently 10ga solid copper which was put in before the water heater and cook top and...
Using the more flexible 8Ga would be much easier with the more flexible 8ga.

Double check the tables to make sure that the CuAl 8ga can handle the current. The equivalence is usually closer to 3 guage sizes and the ampacity of CuAl is the same as the same size Al, so it depends on how heavily you were loading the 10ga.

Not all connectors designed for Cu can handle CuAl. There is a difference in the thermal expansion characteristics and cold flow between Cu and Al and the Cu coating does not change that.
Same with the effects of stranding if the 8ga is finely stranded rather than standard stranded (rolling trippingly off the tongue.)

The jumper cable wire insulation may not be suitable for that voltage and use either.

I would not be comfortable with using that and would spend the money for new stranded Cu if I were in your place.

PS: Skin effect is usually not a consideration in 8ga wire, but to some extent the Cu coating will make it worse, since the Cu layer has a lower resistivity causing it to hog the current even more.

ggunn

Re: copper coated aluminum wire

Shadowcatcher wrote: »

I was thinking of using some 8ga copper coated aluminum wire for some AC application in our Teardrop trailer. Now the back story I picked up some Harbor Freight jumper cables very, flexible copper coated aluminum to make up a tow vehicle jumper to trailer battery, charge when the sun is not enough, cable. I soldered well and is flexible. My understanding is that there is a skin effect using this sort of wire.
I need to rewire the main shore power connection which is currently 10ga solid copper which was put in before the water heater and cook top and...
Using the more flexible 8Ga would be much easier with the more flexible 8ga.

Skin effect is a high frequency AC phenomenon. With DC and 60Hz AC it is not a factor.

inetdog

Re: copper coated aluminum wire

ggunn wrote: »

Skin effect is a high frequency AC phenomenon. With DC and 60Hz AC it is not a factor.

Even at 60Hz it becomes a factor in cable sizes like 4/0. One motivation for using parallel wires in that amp/size range.

mike95490

Re: copper coated aluminum wire

inetdog wrote: »

....I would not be comfortable with using that and would spend the money for new stranded Cu if I were in your place....

I'd abandon the clad wire, and use either new copper or new aluminum.

At the DC and 60hz AC, there is no appreciable "skin effect" the copper cladding is only to make the cheap aluminum wire look like copper wire.

With either wire in a trailer, I would use anti-corrode paste on the connections, just because they will see more moisture than likely in a house.

I thought the gauge translation from copper to aluminum, was aluminum needed 2 sizes larger wire, but 3 would not hurt. [ 8 ga copper = 6 ga aluminum ? ]

Cariboocoot

Re: copper coated aluminum wire

The cladding is to avoid the need for special connection precautions normally needed with aluminium wire.
I'd be curious as to the quality of that cladding and if it wouldn't be possible/likely to cut through that cladding and introduce a pathway for air/moisture to get to the aluminium. Do they recommend using the anti-corrosive grease on this stuff? If so, why bother? You could just use regular aluminium.

Which I personally do not like.

inetdog

Re: copper coated aluminum wire

Cariboocoot wrote: »

The cladding is to avoid the need for special connection precautions normally needed with aluminium wire.

Or, in the case of Harbor Fright jumper cables, just to make them look nicer and more valuable as mentioned earlier by mike.
Since it may not be serving any real purpose, it may be a very thin copper plating rather than the thicker cladding which is required for UL-rated CuAl wire.