Copper VS. Aluminum

[JacksonburgFarmer]

I have a realitivley large project coming up, and I am thinking about using aluminum feeders....

In a search of the forum past posts, I tried to come up with possible issues with this idea, and the only thing I could find is that "aluminum is ok if properly terminated"

In my training/experiance, "properly terminated" for aluminum means to clean, tight connections with proper lugs/connectors, and plenty of De-Ox....

Am I missing something, is there more????

 

[480sparky]

Just terminate it according to the manufacturers specs. I don't think any of them require de-ox any more.

 

[macmikeman]

But the de-ox doesn't hurt any either.

 

[charlietuna]

One other thing--and it is my opinion. Yes, proper terminations with rated compression tools is important, but proper engineering is just as important. Take a hydraulic elevator feeder with four cars and use aluminum and get the load up close to 80% and you'll have problems. Motor loads close to maximum amperages will not hold up using aluminum. A good engineer with over-engineer such a feeder or go to copper.

 

[220/221]

Am I missing something, is there more????

I have seen my share of failed Al feeders underground where in insulation apparantly got scuffed during installation. A couple years of sitting under water in the conduit turns the AL wire into white powder.

 

[480sparky]

I have seen my share of failed Al feeders underground where in insulation apparantly got scuffed during installation. A couple years of sitting under water in the conduit turns the AL wire into white powder.

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[weressl]

I have a realitivley large project coming up, and I am thinking about using aluminum feeders....

In a search of the forum past posts, I tried to come up with possible issues with this idea, and the only thing I could find is that "aluminum is ok if properly terminated"

In my training/experiance, "properly terminated" for aluminum means to clean, tight connections with proper lugs/connectors, and plenty of De-Ox....

Am I missing something, is there more????

Both installation will perform equally if the installation and material selection is proper.

Run the economics, including the installation cost and see where the chips fall. Ex. aluminum is less weight for identical current carying capacity, but it could go the other way if the run is long and (additional)oversizing to compensate for voltage drop. If installed in conduit the same amperage may require bigger conduits. Cu and al metal prices are running together - almost like a cartel - so you may not see great cost advantage one over the other.

Copper corrodes as well, it depends what chemical they encounter. Aluminum oxide is actually a very corrosion resistant material accross the board and forms a continuous 'film' that is actually a barrier.

 

[Cow]

We used to use copper always. Lately in the last year or so, we're probably using 90% AL to 10% Cu for feeders. We still run conduit, we don't direct bury, and we still use USE rather than XHHW insulation. I figure that direct burial USE insulation has to be a little tougher and may last a little longer. I'm very careful pulling into conduit with AL and use plenty of lube. I've fixed so many corroded aluminum wires in the past that I know what happens if you even nick it a little bit.

Making sure the wire doesn't catch on the side of the wooden spools as it's reeling off is definitely something to watch out for.