Aluminum vs copper conductor

[jaraujo1]

I have a debate raging on the use of copper vs aluminum.
I have a project where the bid went over budget. We are looking where we could save money (value engineering) copper vs aluminum is one of the item we are looking into. Does anyone have any comments to make me swing one way or the other?

Thanks for any feedback.

Juan

 

[iwire]

The power companies seem to do fine in most areas with AL.

 

[jaraujo1]

Aluminum vs copper conductor

I am looking for experience from people who have used aluminum from the service to the distribution inside the building. One setback I heard of: requre a lot of maintenance because of "creepage". Current tend to make aluminum expand/contract and therefore make connection loose over time. Any comments?

Juan Araujo,
PE, electrical
CA,NE,TE

 

[petersonra]

Some people do not trust aluminum wiring.

Some specs prohibit it.

Aluminum wire is bigger so if you have to pull it, you need bigger conduits.

Some places it is not as common as copper so is harder to come by, and the choices of insulation are fewer than with copper.

 

[roger]

I have used Aluminum for many services over the past 30 years and have only had one problem which was a nicked conductor in an underground service on the beach.

Aluminum is fine IMO.

Roger

 

[cowboyjwc]

Many contractors are using it for subfeeds. The "new" aluminum has different characteristics than the "old" stuff so I don't believe that your worries are as much of concern as they used to be.

I just got a call where the contractor wants to use it for his branch circuits too.

 

[jaraujo1]

Aluminum vs copper conductor

I dig further....here are some interesting lab test....read the link below.

Juan

--------------------------------------------------------------------

ALUMINUM VERSUS COPPER WIRE TERMINATIONS
From www.cable.alcan.com

Reliable performance from connections of conductors and connectors is essential to the operation of any electrical system. In the competitive environment of today, however, a new criterion has emerged as the search continues for more economical ways of achieving, and surpassing, the high expectations of installers, legislators, and end users. Aluminum alloy conductors offer an option to copper conductors, and Alcan Cable believes that they match the performance of copper in electrical circuits governed by code requirements.

In order to put substance to this claim, a program was designed and carried out for Alcan Cable, by Southern Development Investment Group (SDIG) / Georgia Power Research Center, with the following objectives.

? To verify that connections of AA-8030 aluminum alloy conductors with mechanical screw type connectors perform as well as the similar connections of electrically equivalent copper conductors in a heat cycling test that is more severe than industry accepted standards (UL 486B or CSA C22.2 No. 651 & ANSI C119.4).

? To verify that connections of AA-8030 aluminum alloy conductors with mechanical screw type connectors perform as well as the similar connections of copper conductors in a torque retention test.

? To compare physical properties of AA-8030 and copper conductor materials before and after heat cycling test. Testing can provide an important means of assessing connection performance relative to different connector designs and conductor types. Chosen with care, tests can also provide a convenient indicator of expected life under normal conditions of use. There are a number of different tests which simulate the aging of connectors, the most important of which require cyclical current loading in order to duplicate the repetitive expansion and contraction phases of metal-to-metal contacts encountered in pressure type connectors. Electrical utility standards are generally more demanding due to higher circuit loadings, size for size, than would usually be permitted under National Electrical Code rules.

For the results of this test, visit http://www.mikeholt.com/htmlnews/equipment/aluminumtermination.pdf


Copyright ? 2003 Mike Holt Enterprises,Inc.
1-888-NEC-CODE (1-888-632-2633)

 

[Awg-Dawg]

Some places it is not as common as copper so is harder to come by, and the choices of insulation are fewer than with copper.

Your insulation comment made me recall something.

We did a new office building a couple years ago and when I went back a couple months ago, I went into the electrical room and still smell the aluminum wire.

Does anybody know why it smells that way?

 

[dezwitinc]

If you are concerned about the terminations, use a compression pin connector at the transformer and in your panels.
Visit ilsco.com or Burndy or Blackburn for a complete line of terminators.
Terminated properly, there is absolutely nothing wrong or dangerous about using aluminum conductors.
If you are environmentally conscious, make sure that you recycle your beer cans as these make excellent conductors once they are refined.

 

[brian john]

IMO when properly installed, no issues.

We do 1000's of distribution inspections (IR and EPM's) and in my experience when properly installed, using mechanical connectors, or hypress aluminum performs adequately. When not installed properly aluminum performs like copper
burnt up connections, damaged conductors.

In our IR scans the number one issue we find with aluminum is HOT Mac Adapt type connectors. Not sure if this is due to the improper hypress tool or the connector it self.

 

[masterinbama]

That AL wire

That AL wire

smell reminds me of the Mattell creapy crawlers we used to make as kids. It has it's very own smell much like the old mimiographs we had in school

 

[ed downey]

We have used this on many projects over the years and there has been no issues with the AA-8000 series conductors for feeders 100A and larger.

also the Aluminum conductors are made into compact strands (which kind of look like a pie shape) so they do not require larger conduit size for most feeders.

If you would like to Private message me I will send you a couple of documents that list some of the projects that have used the ALCAN product over the years.

-Ed

 

[infinity]

We always use Hypress lug terminations which eliminates the contraction and expansion issue.

Regarding that aluminum "smell". I would guess that it's the insulation that is giving off the odor. XHHW really has a distinct scent.

 

[brantmacga]

i use aluminum unless space requirements call for smaller conduits, which is rare.

 

[brantmacga]

XHHW really has a distinct scent.

i always thought it smelled like a new tire. especially that w/ the pirelli brand insulation.

 

[peter d]

XHHW really has a distinct scent.

Coming soon to a fragrance counter in your local mall:

XHHW Factor cologne!! For the hard working electrician who really wants to impress the ladies! (or maybe scare them away?????)

 

[abe72487]

Aluminum versus copper

Aluminum versus copper

I have used both but be aware that Al wire needs to be in conduit if in rocky soil because even direct burial will get an pin hole in the insulation and then it will blow up whereas copper will just go to gorund. Also you will need to use an oxide on all terminations with AL wire.

 

[weressl]

Aluminum, shmaliminum, just like everything else when properly installed it will provide long term service just like copper. (And no it doesn't taste just like chicken...)

The material mechanically behaves differently than copper so both in installation material and method allowance should be made. The use of a protective covering paste against corrosion on mechanically connected conductive surfaces is a good practice. The use of as much compression connectors as possible is a prudent measure to assure long term service.

Whilst copper forms a protective copper oxide when corrodes and prevents the corrosion further propagating into the material, aluminum tends to form a powdery salt that propagates throughout corrosion and disintegration of the conductive structure. This is true to normal to medium environmental corrosion, not attack by any alkalies or acids directly or sea-coast environment.

Finally remember to IR scan the installation under load as soon as the installation is complete.

As a side note anodized aluminum conduit held up superbly in comparison to galvanized rigid steel in a 3 year sea-coast exposure experiment.