Aluminum wire going to make a comeback?

[wmetfab]

I have a 200 A 3 phase sub panel fed with about 35m of alum. The wire needs to have di electric grease on the connections which need to be checked for tightness every couple years or so.
The problem is the coeficient of expansion, alum moves a lot compared to the copper, thats why it was so troublesome in residential wiring.
I am not an electrician.

 

[mickeyf]

I always tune in to these threads about a week late...

I thought it caused some fires due to not being as pliable as copper.

My impression was that because aluminum forms a surface oxide layer when exposed, and that oxide is at least partially an insulator, that unless the connections were made properly that extra resistance caused heat, and potentially fires.

For most of my life doing 'homeowner permit' wiring, I have understood that Aluminum was disallowed for diy'ers, but when I mentioned this to the Inspector when he check my recent workshop wiring, he said "That's old school", implying that it was now allowed. On my previous workshop (with which I had professional help) we ran aluminum teck from a new panel to the 100A shop panel. I don't recall the length, but it was a fair ways, and would have cost much more if copper had been used.

 

[BaitMaster]

I always tune in to these threads about a week late...


My impression was that because aluminum forms a surface oxide layer when exposed, and that oxide is at least partially an insulator, that unless the connections were made properly that extra resistance caused heat, and potentially fires.

For most of my life doing 'homeowner permit' wiring, I have understood that Aluminum was disallowed for diy'ers, but when I mentioned this to the Inspector when he check my recent workshop wiring, he said "That's old school", implying that it was now allowed. On my previous workshop (with which I had professional help) we ran aluminum teck from a new panel to the 100A shop panel. I don't recall the length, but it was a fair ways, and would have cost much more if copper had been used.

Aluminum armoured cable is type ACWU.

Teck cable is copper.

 

[slow-poke]

We live in a bungalow, it has a 400A service, 200 for the house and 200A was for the pool heater that is no more (pool removed). I picked up a new in the box 200A panel on Kijiji for $100 and had an electrician divert the old pool feed to the new 200A panel in the garage. The electrician used the aluminum version of the teck cable I guess ACWU. No shortage of power in the garage.