Aluminum vs Copper

[bstoin]

Aluminum makes great soda cans

Yeah, but my beer always tastes better from bottles.:wink:

 

[shaner2007]

I Have done over 1000 units of condo's that all had AL feed to them

I Have done over 1000 units of condo's that all had AL feed to them

Aluminum wiring is 100% safe as long as it is installed correctly like anything else we do. A joint compound capable of penetrating the oxide film and perventing its reforming should be used I have always just gave a quick brush with a wire brush and used a compound called penatrox (dont quote me on the spelling) and its good to go.Just be careful on equipment because some of the lugs and space for wire to be terminated is too small for AL. As far as size is concerned the size is as followed C = 1.8 plus 32 Fahrenheit
AWG Rated at 85-90 C with a Ambient Temperture 30 C
12 15A
10 25A
8 30A
6 55A
4 65A
3 75A
2 95A
1 105A
0 120A
00 145A
000 165A
0000 185A
250 215A
300 240A
Also watch were you install it if its in a high corosive area I would stay away from AL

 

[don_resqcapt19]

Shaner,

Also watch were you install it if its in a high corosive area I would stay away from AL

If the insided of the enclosure is a corrosive area, then you have a lot of other problems too.

 

[rattus]

The Original Question:

The Original Question:

With the price of copper so high, many contractors have been submitting on aluminum conductor feeders for panelboards and HVAC equipment. I understand that the AL wire has less ampacity so they actual size of the conductor would need to be reviewed, but are there any reasons not to accept AL wiring in lieu of copper? This typically comes up in the VE process.

Back to your original question: The consensus seems to be that you would not use AL in corrosive environments such as plating shops, battery shops, swimming pools, seaside buildings, etc.

Also, it seems to me to be a good idea to use some sort of protective coating on CU in such environments. Maybe one of our experts can opine on this idea.

 

[birtclp]

As a specifying engineer I normally specify copper feeders. Both AL & CU are safe and will function well when installed properly, but CU is much more forgiving (for lack of a better word) than AL. Mis-installations of AL feeders are more likely and more common than with CU feeders. Basically there are more things that can go wrong with AL than with CU.

I do run into projects where budget requires use of AL feeders and in 18 years have only had two AL issues on projects we designed out of probably 50 AL feeder projects. One due to poor termination of feeders at panel and one due to contractor using improper sized feeder (matched CU feeder size indicated on dwgs despite VE changeorder for larger AL feeder). Both were design-build projects where we did not perform a final walk-thru and thus did not catch mistakes. In each case heat (wire, termination, and breakers) alerted maintenance personnel who contacted us. In both cases the heat was excessive - could touch breakers but could not keep hand on them for more than a few seconds. Luckily no fires or injuries in either case.

In addition to these two instances we were called in on a project designed by another engineer where poor termination of AL feeders was causing breaker in panel to heat. Have also worked on two apartment projects where fires from aluminum branch circuit wiring (both instances CU only receptacles used with #12 AL).

I know if CU terminated improperly or if wrong size CU conductors used the same problems could occur, but in same 18 years I have designed well over 500 CU feeder projects with no similar instances.

So yes, AL feeders installed, sized, & terminated PROPERLY will work just as well as CU feeders and are just as safe as CU feeders - with "properly" being the key word.

With CU prices skying again, I expect to see more and more VE request for AL feeders.

 

[George Stolz]

This is an old thread. If someone has something to add about copper v. aluminum, feel free to start a new one.