aluminum wiring

[billdozier]

Hey guys went on a service job tonight doing an al/cpr device changeout. The original electricians cut off the grounds maybe 3 inches in the boxes. What is the proper way of bonding these plugs? Wagos? Screw on the clamps in the box? WIth a copper wire on a ground screw coming off the box? Wirenuts not an option not enough wires. How would you fix it?

 

[guschash]

I would ground the box with that short wire and use self-grounding receptacles.

 

[al hildenbrand]

I would ground the box with that short wire and use self-grounding receptacles.

I'll bet the boxes are non-metallic.

Short aluminum EGCs. . . yeesh. And the boxes are probably already "hammer handle tight". AlCop, Copalum, or Purple Ideals, or someother type of listed Al/Cu pressure connector needs to be used.

 

[MarkyMarkNC]

Alumiconns.....

http://www.alcopstore.com/index.asp?PageAction=VIEWCATS&Category=2

With that small of a wire, they will still be a pain to install, but definitely do-able.

Why is it that all houses wired in aluminum seem to have short pigtails? I just completely re-wired a house that was aluminum, and it had the most consistently short pigtails of any house I'd ever seen.

 

[al hildenbrand]

Why is it that all houses wired in aluminum seem to have short pigtails?

I well remember wiring a couple houses, when I was apprenticing back in the late 60's, where my Master didn't give a rip about box volume calcs, and approached the whole matter as if the box was sized based upon the size of the breaker.

That is, one used the same size boxes for the same roping that one would with copper wire.

Boy we had to keep the leads short to get 'em in under the devices. . . .

 

[billdozier]

Al did they break off just as easily back then or is that due to heating and expanding? Had to change the panel today. Biggest pita ive ever had. Ended up splitbolting the 10 wires cause they were stranded and would not fit under square d qos pressure lugs. Learned so much today. Thank God for modern concepts.

 

[al hildenbrand]

Al did they break off just as easily back then or is that due to heating and expanding?

That early alloy was supple, but nicks would migrate through the conductor. Most stripping methods commonly accepted left nicks. . . bad juju.

The thermal expansion of the aluminum under plain old device terminal screws deformed the conductor leading to higher terminal resistance, greater heating and more deformation. . . vicious cycle.