ALUMINUM WIRING FOR SMALLER CABLE SIZES

[PE (always learning)]

Random question, but does it make sense to use aluminum cable for smaller feeds on a commercial project. I usually never see anyone use aluminum cable for anything under a #2 AWG. I've heard that it is because of the tendency for aluminum to expand and contract that people don't like to use it on smaller connections because they can become loose, but has anyone ever done a project where it was fully aluminum down to the #12 AWG cable?

 

[tom baker]

IMO, no. Not sure if AL wire is available in smaller sizes
All those homes wired with 12 AWG AL in the 70s are having issues with the terminations to the receptacles
I wouldn't go below 2 AWG AL and I always used compression lugs.

 

[augie47]

I think in individual conductors Southwire shows a #6 AL as smallest.
I've never seen smaller than #2 on commercial installations other than an occasional #6 SE cable.
With Cu prices skyrocketing that may change.

 

[tom baker]

There was a change in the 2020 NEC that added copper-clad AL in several locations. There is a definition of copper clad AL, so maybe the additions ( see 310.3 (A) are to allow more uses of this product. A clue is who submitted the change

 

[steve66]

A lot of (or maybe all?) receptacles and switches will only be good for copper conductors. For example, the first receptacle I found online (hubbell gf15) lists copper conductors only.

 

[kwired]

I think in individual conductors Southwire shows a #6 AL as smallest.
I've never seen smaller than #2 on commercial installations other than an occasional #6 SE cable.
With Cu prices skyrocketing that may change.

#6 is smallest AFAIK, but seldom ever see or use it. I use quite a bit of #4 AL. Is good for 60 amp feeders. For irrigation applications and long runs run a lot of #4 AL quad instead of 10 AWG copper.

Also use a lot of #4 AL for equipment ground for 101-200 amp feeders that are also using larger AL conductors

 

[petersonra]

I understand the fear of using small size AL conductors due to the problems that existed back 50+ years ago with the use of device that were not suitable for AL wire, but it was never an issue with larger sizes. It seems like AL wiring got a bad rap it did not deserve.

 

[kwired]

I understand the fear of using small size AL conductors due to the problems that existed back 50+ years ago with the use of device that were not suitable for AL wire, but it was never an issue with larger sizes. It seems like AL wiring got a bad rap it did not deserve.

We use better aluminum alloys now than we did 50+ years ago as well, we had better alloys around 30 years ago for that matter.

Still probably not a great idea to use solid aluminum in 12-10 or maybe even 8 AWG sizes though.