aluminum in house wiring

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caosesvida

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Does anyone still use aluminum #12 for 15 amp circuits? I looked in the archives but didn't see much there. It had such a bad rap in the late 60's that I guess I just assumed ( not a good idea)it had been taken out of the code. I looked through and it still allows #12, and I didn't see any reference to restrictions for residential use. Was it just through general concensus that people stopped using it, or because of the cost of the al/cu receptacles?
thanks. I know its used extensively for #8 and up.

[ April 13, 2005, 09:17 AM: Message edited by: caosesvida ]
 
Re: aluminum in house wiring

It's not a good idea. The terminations can be a fire hazard. From what I understand you wont be able to find small gauge Al conductors.

I was recently considering aluminum for a subpanel feeder but I wouldn't consider it for branch circuits.
 
Re: aluminum in house wiring

Norb, I'm pleased to see your pictures. I ran into the same type of situation about 5 yrs. ago. When I pulled the receptacle out of the box it was still energized & the side of the receptacle was glowing red. Alum. is not a good thing for small appliance & lighting circuits!!!!
 
Re: aluminum in house wiring

The circuit was still energized. I tried to short the circuit to shut it down and did not work either. As I started to move the receptacle it began to arc and glow red. I went to the basement and turned off the main. Man were we lucky.

I recalled a link on the home page of this forum, so I contacted them and they have put me in touch with a local contractor who is COPALUM certified. I have given this contact to my customer.

I hate Aluminum for branch circuits.

Norb
 
Re: aluminum in house wiring

I hope you don't mind 1793.

p4130020.jpg
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Re: aluminum in house wiring

There were several components to aluminum wiring failures:

1. Reynolds was making wire that was a very soft alloy compared to Alcan's Stabiloy(R). Electrical conductor aluminum needs to be 99% or better purity but must also contain a dash of silicon and magnesium to not be to soft to withstand normal joint pressure.

2. Cheap STEEL terminals. You can only expect so much performance from a 69 cent receptacle.

3. There was so much emphasis on speed that electricians were not cleaning the wires like old timers did. The result was that cheap STEEL binding screws were doing the cleaning and carrying all of the current. In fact, after the dust settled it turned out that there were a lot of copper wiring failures.

In fact, there are 2 antioxidants on the market that are formulated for use only on copper wire. Thanks to catalytic converters copper that is outdoors oxidizes just as fast as aluminum. For solidly copper wire you usually get too much voltage drop or an open circuit before it burns up.

I have used Stabiloy(R) wire to hook up heavy industrial machines and every time my aluminum wiring was a 100% success story. Anything that is instrinsically wrong with stabiloy(R) can be cured with silicon carbide abrasive paper, elbow grease, and electrical grease.

Dr. Jesse Aronstein who is the foremost authority on copper and aluminum wiring failures conducted tests that were far more rigorous than the UL tests on both aluminum and copper wire as a matter of scientific control. A lot of the problems that affect aluminum wire also affect copper wire. He found that a wire brush is 100% INEFFECTIVE at removing aluminum oxide. The most effective agent for removing aluminum oxide is #220 or #240 silicon carbide abrasive paper.

Back during World War 2 the Signal Corps specification was that you had to remove all copper oxide from copper wire using diagonal currets or sandpaper. Repairs that I have had to perform on malfunctioning copper wiring proves that yes you must remove copper oxide from ALL the wire strands.
 
Re: aluminum in house wiring

I forgot to add that National Electrical Code article 110.mumblesomething requires a thoroughly good electrical connection but does not define what a thoroughly good electrical connection is.
 
Re: aluminum in house wiring

Mc5w,

Are you trying to illustrate that aluminum conductor terminations are maybe slightly less desirable than copper conductor terminations? :confused:

Are you advocating the use of aluminum branch cicuit conductors? :confused:

Maybe I'm misunderstanding.
 
Re: aluminum in house wiring

There were major problems with aluminum branch circuit conductors installed prior to 1973 or 74. At that time the new alloy and CO/ALR rated devices came on the market. There is no evidence of problems with the newer products, but because of all of the problems with the older products few people want to use aluminum for these applications and no company is making it in 15 and 20A sizes at this time.
Don
 
Re: aluminum in house wiring

thanks for all the replies, I have seen all those loverly receptacles around here, The best is all the mobile homes that were run through at the time with FPE breakers panels.We also have a group of very expensive beach front houses with aluminum, and to top it off the electrican ran 2, 14/2's for the three and four way switches, that was a challenge finding those mistakes.I was talking to anther group on a different forum, and they had indicated that aluminum was still being used in california. I hadn't seen romex (nm) in aluminum since the early 70's.
 
Re: aluminum in house wiring

Just curious. Is that recep co/alr? It doesnt look like the ones available now, which have the retainer(?) tab sticking out. :eek:
 
Re: aluminum in house wiring

why would any self respecting electrician even think of using a known fire maker.That junk isnt good enough to even tie ladders on the roof :mad: :mad: :mad:
 
Re: aluminum in house wiring

By Cosmos:

Any guesses whether an AFCI breaker would have prevented this ?
Click to expand...
My uninformed "guess" is that an AFI would be perfectly worthless in preventing the type of heating created at the terminations of aluminum conductors. Without trying to "guess" in further detail, maybe someone else knows something more about it than I do.
 
Re: aluminum in house wiring

It was the Electricians, not the alum. wire,that are/were the Fire Makers. The self respecting Electricians installed the products properly,and the 10's of 1000's of homes that have never had problems are proof that the installer not the product is the culprit. The same type of installers have the skills to do the same damage with copper wire. This is why I'm not an advocate of alum.

frank
 
Re: aluminum in house wiring

I'm wagering that it's way easier to make it dangerous with aluminum. And that's pretty much good enough for me.

Edit: Left out a word.

[ April 15, 2005, 10:48 PM: Message edited by: physis ]
 
Re: aluminum in house wiring

The first aluminum branch circuit that I installed was a 200 amp 240 volt corner grounded 3-phase circuit using 4/0 SER cable. This ran into a 75 KVA transformer that stepped up to 480 volts ungrounded. I then ran #2 aluminum SER cable a few feet to a plastics machine with 60 KW of electric heaters.

The 4/0 aluminum was carrying the full 144 amps that the rules for electric heater would allow. During production half the heaters ran 100% duty cycle and the other half about 95% duty cycle. Both heater banks cycled more than that during breaks. This machine ran 24/7 for 6 months except for Thanksgiving, Christmas, and 2 breakdowns.

During the first 2 months of this machine's life the copper wiring in the machine broke down twice. The first time was that somebody forgot to put in a heat shield and it cooked its own control box. The second time the builder has extended 180 degree Celsius 7-strand #12 wire directly from the moving bank of heaters to the control box. 7-strand nickel plated copper wire is not meant to be flexed around like cords are. I had to interpose some lengths of industrial rubber cord to fix the problem.

Since then I have done both temporary and permanent hookups of industrial machinery using aluminum SER cable. I have also done 200 amp residential feeders using aluminum. Never had a problem with my aluminum wiring. Problems that I have encountered are usually with somebody else's copper wiring that was not cleaned to get rid of copper oxide.
 
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