Can Aluminum Replace Copper, take ... 2

This was tried for residential wiring in the 70s, and didn't really take off, for a number of reasons...

but materials scientists assert that they've figured out ways to modify the fundamental properties of metals like aluminum to allow it to have electrical conductivity 80-90% that of copper, instead of the current 60%.

I wouldn't put off your black-box rewire right now, but...

The primary reason, of course, was that they didn't do their figures correctly on screw joints on things like switches and receptacles, and caused a lot of house fires...

Jay Ashworth said:

The primary reason, of course, was that they didn't do their figures correctly on screw joints on things like switches and receptacles, and caused a lot of house fires...

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@Jay Ashworth Aluminum being softer than copper, migrated / escaped from the pressure exerted by screws bearing down on it. Corrosion from dissimilar metals was also a problem which was dealt with by the application of a product called No-Alox. Terminals were developed to keep the aluminum confined when under pressure.
Dumb acronym. SACN. Solid Aluminum Conductors Necessary.
Toodleoo!
Ron Hebbard

Indeed. And they redesigned the fixtures (as you allude to), and marked them differently; I believe the original 'bad' ones were marked CU/AL and the redesigned, safe(r) ones were marked CO/ALR.

[ looks ]

Apparently, that's true, but the *current* received wisdom is that the CO/ALR fixtures aren't good enough either:


If you live in a house with a manufacture date between roughly 196[edit:]5 and 1975 or so, you should check to see if it's wired with aluminum wiring, and consult a qualified master electrician -- preferably one in his 50s or 60s -- to see what, if anything, you should do about that. Probably the easiest way to confirm it is to pull the cover off your master electrical panel, as you don't have to move any wire or devices to do that. You're a grownup, don't do that if you don't know how.

This other page at the bogglingly-named Insectapedia makes some suggestions about what to do in that situation, and it is decidedly non-trivial stuff:

Jay Ashworth said:

This other page at the bogglingly-named Insectapedia makes some suggestions about what to do in that situation, and it is decidedly non-trivial stuff:

How to repair aluminum wiring: recommended methods How to Reduce the Risk of Aluminum Wiring Fires

How to reduce the risks associated with aluminum electrical wiring - a practical guide shows which aluminum wiriing connectors can be used successfully to connect aluminum conductor wires to copper-wired devices (such as lighting fixtures or fans) and to electrical receptacles (

inspectapedia.com

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The name makes a lot more sense if you include the "p" that you missed...

Malabaristo said:

The name makes a lot more sense if you include the "p" that you missed...

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Well what the heck fun would it be if I didn't misread it on two successive pages??



Caffeine hasn't kicked in. That's my story... and I'm stickin' to it.

I clicked this thread thinking we were all going back to aluminum nico sleeves.

GoxBoxSocks said:

I clicked this thread thinking we were all going back to aluminum nico sleeves.

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[ goggles ] [ googles ]

Oh.

In fact, there *are* compression splices you can use to put copper pigtails on aluminum house wiring, as that website notes. Tyco will only *lease* you the compression tool, after you pass their classes, which presumably is an attempt to reduce their insurance exposure from people's houses burning down. It's apparently only half as much to do that as to totally rewire with copper; I'm not sure I wouldn't just spend the money. If I had it.

Way back when I was an electrician making older residential properties compliant as they were vacated took up some portion of my time. Pulling out SOME Al wire, but largely leaving it alone.
Truth is, as mentioned Aluminum wire itself is perfectly fine as long as it isn't mechanically disturbed much (will eventually deteriorate) . As long as it's not exposed and proper connections are used it's all fine. A common tactic is to use AL-CU marrettes and noalox to put in copper "tails" for newer Cu only devices (receptacles and switches) and otherwise using Cu-Al rated devices (less common as they are more expensive).
Saves a LOT of money compared to completely rewiring to Copper.
As mentioned NEVER use Cu only devices with Al wire.

Also, Aluminum wire is still commonly used for service conductors and the like. The lugs are designed to be Al compatible and you just need to remember the noalox. There is a reason that ampacities for aluminum wire are in the code book as well, as they differ from Copper. A big thing to keep in mind.