Aluminum wire and antioxidants...

[jrannis]

If in doubt, do what the manufacturer recommends: http://www.southwire.com/Southwire/StaticFiles/Text/commonQuestions.pdf

Thanks for the link.
This is something usually ignored by those who think copper is the better conductor to use.

 

[glene77is]

Pierre,

At the Inspect-NY website,
the section by Aronstein points out that the Alum should be treated in this sequence:
(1) apply antiOx.
(2) abrade the surface (dragging the antiOx into the abraded surface).

He suggests that the oxidation forms immediately, and quickly becomes many molecules deep. The oxidation is not a 'coating' on the surface, but is like an anodizing process, which is many molecules deep. This depth is why he suggests the (1) (2) sequence.

Check it out sometime, it is a good read of some 40 web pages.

...
Here is my previous post related to an 'alternative' to AntiOx
(BTW, I don't think a real alternative exists):

to Peter D:

I have repaired fire damaged residentials.
In the process, I experimented with the 'purple' wirenuts
and three NoOx compounds available today.
The 'Purple' wirenuts burn and melt
when the NoOx is lite by a match.

I tried the same with some hard-shell wirenuts,
and the NoOx burned,
but the hard-shell wirenuts only smoldered some.

I checked the specs,
and the hard-shell have a much higher temperature rating.

Wish I could remember the name of the high-temp wirenut.
I used them all up on a job.

Anyway,
some of the material we use to prevent fires
will burn when lite by a match.

Makes me more careful than ever.
__________________

 

[glene77is]

RockyD, and Larry Fine,

Excellent Procedure!

(1) Apply AntiOx,
(2) then Abrade into the surface.

See the Inspect-NY website for Aronstein's Aluminum Wiring section.
He supports this method with good evidence and photos.

...

 

[Pierre C Belarge]

See the Inspect-NY website for Aronstein's Aluminum Wiring section.
He supports this method with good evidence and photos.

...

When it comes to Mr. Aronstein's info about the Model 65 Twister wirenut, I believe he had outside influence in regards to his article. It was written the summer before the Ideal wirenut was released to public ('93), and if you look at the pictures, it shows other wirenuts, not the purple wirenut.

I performed my own field tests on Ideal's wirenuts and had in writing a statement from UL in regards to the performance of the same item.

He has some interesting articles on his site, but I am not impressed with his handling of aluminum wiring or termination articles.

 

[formula1]

how often does this occur

Oxygen has 6 electrons in its valence shell, making it a somwhat good insulator.
Aluminum has 3 electrons in its valence shell, making it a good conductor.



When an oxygen atom meets with a Aluminum atom, the two atoms form a molecule called Aluminum Oxide (Al2O3).
This chemical reaction starts to take place as soon as the Aluminum is open to oxygen.
The Aluminum Oxide forms a very strong coating on the surface of the conductor, which is very high in resistance.

The anti-oxidant helps to keep this from occuring.

 

[Pierre C Belarge]

how often does this occur

As soon as the aluminum conductor is exposed to air.

 

[formula1]

how long does it take alu. to have problems when used in a res. service is there a life span is there a life for copper anybody anybody

 

[Pierre C Belarge]

The conductor itself is very stable under normal environments.

It is the insulation that has a shorter life span.

There are conditions such as load, heat, cleanliness of environment (dust, oil, etc...), installation practice, that will either adversely or not-adversely affect the lifespan of the insulation.

In general, the lifespan of the different insulations used for house installations has a substantial lifespan, that will under normal conditions probably outlast most of us here.

 

[formula1]

so alu. has a bad rap for no reason or is it due to alu. of old, bidding on jobs is getting more cut throat and alu. services are getting more popular to save money

 

[LLSolutions]

so alu. has a bad rap for no reason or is it due to alu. of old,

A bit of both I believe, Al in the home has led to most of the bad rap, due the the greater expansion of Al from heat it begins to loosen at many devices and thus leads to high resistance connections which adds to heat and sometimes fire. Al has had greater success in the commercial and industrial world when used for feeders and larger branch circuit applications, and the obvious ease of installation and cost vs. copper. As I stated earlier Al can be just as good as copper when installer right. Almost all the Medium voltage applications on Long Island are done in Al. Many of installer myself included abuse copper when we install it, think of the way we skin larger conductors the extreme over tightening of lugs and connectors bending radiuses when make, Al can't be treated in such a matter. Most of us would agree that the installation method is what creates the long lasting installations, I've seen Knob & Tube outlast NM when done right.

 

[Fulthrotl]

so alu. has a bad rap for no reason or is it due to alu. of old, bidding on jobs is getting more cut throat and alu. services are getting more popular to save money

aluminum wire in residential branch circuits has a bad reputation....
it's earned every bit of it, one burning house at a time.

as for large feeders, as long as they are properly terminated, aluminum wire
works fine. there are a number of means and methods that work, but
if you want a long term connection, think hipress, or a swaged fitting of
some sort. setscrew lugs need retorquing, something that doesn't always
happen..... my experience with hipress lugs on aluminum cable is they are
as reliable as copper. i've also pigtailed large aluminum feeders with copper
using hipress butt splices, and 3m cold shrink tubing. this works well with
installed feeders where the end of the conductor is deformed from being
torqued, and not easily hipressed....

 

[don_resqcapt19]

aluminum wire in residential branch circuits has a bad reputation....
it's earned every bit of it, one burning house at a time.

But that is with the old aluminum alloy and without CO/ALR devices. The 15 and 20 amp new aluminum alloy was not on the market very long because of the deservedly poor reputation of the old aluminum conductors, but it has not had the problems of that the old stuff has.

 

[hillbilly]

Wiring my cousin's house...a family deal....low cost and save a buck if I can.

Yesterday I set the Meter Can and directly inside (back to back), I mounted a 200A Main Breaker panel.
Out of Meter, thru close nipple and into Panel.

Looking thru my wire scrap, I found a 6' piece of Southwire USE-2 "Alumaflex" Mobile Home Feeder Cable, 4/0,4/0,2/0,#2 (cross rated RHH, RHW).
I discarded the #2 grounding conductor, and use the remaining three conductors for the Service entrance.
This particular cable is very soft and easy to bend.
That and the cross rating makes it ideal for service cable, especially if you're entering the dwelling with it.

I also used N0-lox on the terminations and worked it into the strands with a wire brush.
I know one particular inspector that will fail a installation if he can't see brush marks where the Anti-oxidant has been applied.
It's required where I am, and standard procedure for me.:smile:
That and using a torque wrench to tighten the terminals.

I always remove the set screws on the terminals and coat them with anti-oxidant too.
I had a bad experience one time with a terminal set screw that had oxidized, and caused me to have a customers electrical service disconnected for about 4 hours longer than I (and she) had planned..

steve

 

[Fulthrotl]

But that is with the old aluminum alloy and without CO/ALR devices. The 15 and 20 amp new aluminum alloy was not on the market very long because of the deservedly poor reputation of the old aluminum conductors, but it has not had the problems of that the old stuff has.

you are referring to the copper clad aluminum wiring, by "new" alloy?

copper cladding is nice, but aluminum still has a coefficient of expansion
that is 137% that of copper. this means it'll expand and contract a third
more than copper, and loosen up any pressure connection devices quicker
than copper.

surface oxidation isn't a problem, but expansion and ductility are still
there, and there is no resolution to either problem. the oxidation, in
my not so humble opinion, is less of a problem than the expansion, which
will loosen every wire nut between the blow dryer in the bathroom, and
the panel, given a couple years......

 

[quogueelectric]

Question for those that DO use Noalox, how many actually read the directions and install it correctly?

I have been waiting for this question all of my life!!!!! I do I do!!!!

 

[don_resqcapt19]

you are referring to the copper clad aluminum wiring, by "new" alloy?
copper cladding is nice, but aluminum still has a coefficient of expansion
that is 137% that of copper. this means it'll expand and contract a third
more than copper, and loosen up any pressure connection devices quicker
than copper.

No, I am not talking about copper clad aluminum. About 1973 or 1974 the actual make up of the aluminum alloy used for 15 and 20 amp conductors was changed and at the same time the CO/ALR devices were made available. The material used for the screw terminals on these devices was changed so that it would have thermal expansion properties very close to that of the conductor itself. You are correct that with the original aluminum and standard devices this expansion and contraction was a major problem. The new alloy aluminum was not on the market very long as it could not overcome the bad reputation of the old stuff. There is not a lot of installations out there with the new wire and devices, but I worked on the install of a couple of apartment complexes with the new stuff as an apprentice and then ran the shop sevice truck for a number of years afther that. We experienced no more problems with the aluminum projects that we did with out copper projects...and yes we were the only ones doing service work on those projects. The only real issue was one building that lost its roof in a storm and had water damage. In that unit there were some failures of the wirenuts that we did not see in the other buildings.

 

[Fulthrotl]

No, I am not talking about copper clad aluminum. About 1973 or 1974 the actual make up of the aluminum alloy used for 15 and 20 amp conductors was changed and at the same time the CO/ALR devices were made available. The material used for the screw terminals on these devices was changed so that it would have thermal expansion properties very close to that of the conductor itself. You are correct that with the original aluminum and standard devices this expansion and contraction was a major problem. The new alloy aluminum was not on the market very long as it could not overcome the bad reputation of the old stuff.

interesting, i entered the trade in 1977, so the stuff that was in common
usage in romex at that point would have been the newer stuff...?
everything i remember seeing was copper clad aluminum. there were only
three contractors still using aluminum romex at that point, and by 1978,
there was only one diehard still using it in this area.

 

[don_resqcapt19]

interesting, i entered the trade in 1977, so the stuff that was in common
usage in romex at that point would have been the newer stuff...?
everything i remember seeing was copper clad aluminum. there were only
three contractors still using aluminum romex at that point, and by 1978,
there was only one diehard still using it in this area.

I think that the NM conductors would have been the new alloy. Our job was an EMT job so we did not use NM. I am not sure when the 15 and 20 amp aluminum conductors disappeared from the market, but I think it was around 78 or 79. I never installed any copper clad and don't know if that used the new alloy or not.

 

[B4T]

Pay me now or pay me later..

Pay me now or pay me later..

I won't do a service with aluminum wire.. I have seen too many melted lugs that turned into changing the entire service because EVERY wire was short when entering into a new meter pan. Money saved in the beginning in not close what a repair costs later down the line

 

[brian john]

I won't do a service with aluminum wire.. I have seen too many melted lugs that turned into changing the entire service because EVERY wire was short when entering into a new meter pan. Money saved in the beginning in not close what a repair costs later down the line

So you have a bunch of lousy electricians in you area? Because when properly installed there is not an issue.