Aluminum wire and antioxidants...

[BKDog]

Yesterday we had a rep from a company come in to our school and give a presentation on aluminum wire. This was only in applications of 50 Amps and above. Ease of bending, weight of the wire, both moving it and pulling it, and other subjects were covered. One thing we discussed was AL/CU rated lugs. These lugs are made of Aluminum. Why then do we put an antioxidant on aluminum wire when almost all the lugs I see these days are AL/CU and not on copper wire under those same lugs. Has anyone found a reference to antioxidents being code required for aluminum wire? Or even copper?

 

[raider1]

HERE is a link to a thread on this topic. This has been discussed many time before on this site.

The use of an anti-oxidant compound would be a manufactures requirement not an NEC requirement.

Chris

 

[kjless]

southwire

southwire

i think the wire your talking about is simpull wire made by southwire. it is the best wire i have ever worked with. it has lube already on the wire, its marked with footage and they make compact aluminum with thhn insulation. so like a 900 KCMIL is pretty much the same size as a 750 copper thhn conductor. pretty neat stuff. they also just came out with new mc wire.

 

[jrannis]

I think the new aluminum wire is the best thing ever. Its great not to have to smash up your hands and ruin your body wrestling copper.
I use it every chance I get.
For what ever reason, I always put no-lox on them.
Ive read in more than one place to do the same with copper.

 

[LarryFine]

I always put no-lox on them.

That's funny; I put no lox on my bagel w/cream cheese.

 

[jrannis]

That's funny; I put no lox on my bagel w/cream cheese.

No fishy smell and 30% less fat

 

[whillis]

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

 

[steelersman]

All I know is blueberries are high in antioxidants and antioxidants are good for you.

 

[Pierre C Belarge]

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.

 

[wptski]

Noalox? Anti-Oxidant Compound is the name of the Ideal product.

 

[BKDog]

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.

The comment the rep had about the no ox was that it will not make a difference under the actual areas that the contact is being made between the conductor and the lug. Because of the pressure he insisted that there would be no appreciable oxidation.

 

[BKDog]

You guys need to eat something when you take break...everything seems to bring the conversation around to food.:grin:

 

[LLSolutions]

Code requirement or not oxidation is going to take place on that cable even if squeezed in a pressure connector, this is something that starts on an atomic level. Ok the cable might not look like it was salvaged from the titanic or anything like that but it may be a small film not noticeable to the eye that increases resistance and adds to heat over time. I prefer to use the Anti Oxidant anytime i use AL. Aluminum is just as good and durable as copper when PROPERLY installed and heaven forbid we use all that money we saved to buy a torque wrench, over tightening of AL has got to be one of the most common mistakes I see.

 

[stickboy1375]

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

 

[Rockyd]

Proper installation of anti-oxidant is done with a little stainless steel brush. Put the de-ox on the brush, now brush it into the wire so that there is no air contact. 110.12 install.

 

[LarryFine]

The comment the rep had about the no ox was that it will not make a difference under the actual areas that the contact is being made between the conductor and the lug. Because of the pressure he insisted that there would be no appreciable oxidation.

When's the last time he measured an oxygen molecule? :smile:

It may take more than just pressure to assure a gas-tight connection.

 

[LarryFine]

Proper installation of anti-oxidant is done with a little stainless steel brush. Put the de-ox on the brush, now brush it into the wire so that there is no air contact. 110.12 install.

I thought it said to apply the paste onto the conductor, and then wire-brush through the paste.

 

[Rockyd]

Join Date: Apr 2004
Location: Anchorage, Alaska/ Snowbirding, Nevada
Posts: 1,000

I thought it said to apply the paste onto the conductor, and then wire-brush through the paste.

I've been around for a while, I'll decide how that action happens!

 

[quogueelectric]

When I saw the alluminum cable installation movie in 1984 it said to put the paste on the conductor and brush it in. This was to keep the aluminum oxide from forming to keep the paste from allowing oxygen to penetrate. A hypress would create an entirely different environment of high pressures and conductive materials.

 

[Rockyd]

Okay, I can change to that, Don't see the difference in "shielding" from the oxidation process, of one process over the other.