Aluminum service wire

[Buckcreek]

I was pricing wire for service to my poll barn , aluminum service wire was around $300. and copper was over $1000. My Dad does not like the idea to use aluminum but i believe that is all i can afford. what to the electricians on here think about it. The aluminum wire is for 100amp service it will be ran from a 200 amp service for a mobile home . it will be close to if not a little more than 300'. The man at state electric store said it would work very well. How will this affect power in my home.

 

[EdKing]

The only concern with aluminum wire is to make sure the hardware is specified for use with aluminum. If the terminals are not specified as "for use with aluminum" you can get dissimilar metal corrosion, leading to heat build up and possibly a fire. Also make sure you use a corrosion inhibitor on your hookups.

 

[EddieWalker]

Due to the price difference, allot of people use aluminum over copper with great results. Copper is better, but with so much aluminum out there being used in just about every application, it's not something to shy away from.

Some of the concerns and complaints about aluminum is the oxidation at the terminals. This causes them to loosen up over time and you end up retightening them every year.

To eliminate this I use an oxide inhibiting compound called Contax. It's a thick black fluid that you just put on the exposed wire before tighting it down.

I bought it at the electric supply house and have never looked for it at the box stores. Not sure what they have or if it's as good.

The other issue with aluminum is you have to use thicker wire for the same run compared to copper. It's still cheaper, but you have to make sure your comparing the same capacities of the wire, not the size.

Eddie

 

[Buckcreek]

The wire he quoted me was suppose to be the proper size for the application. It was , I think #2 service wire. It had three runs of copper wire and another run of a green covered wire for ground . it was direct burieal wire. but if i use it i will still put it in pvc. He said it was 100 amp service wire.This is a stupid question but is the smaller the number the bigger the wire.. /forums/images/graemlins/confused.gif /forums/images/graemlins/grin.gif

 

[VA_Joe]

As the other guys said - nothing wrong with AL wire as long as the contact antioxidant is used. The relative cost difference is a good reason to use it (500' spools of #12 copper have gone from $20 to $35 in the last year or so).

As Eddie said - with AL you will need to use a larger wire to get the same amperage. This can make it difficult to install the 100 amp breaker in the existing main panel which is already full of wires and - if it is an older breaker box - it will likely be narrower than a more modern one (making it more difficult to bend the wire).

Since this is for an out building - I would check to see if you can hook it up to the meter base (and yes - after the meter) vice the main panel. Depending on the size of your meter base - your power company may allow this (although if you tell them - they would likely want to charge a fee for coming out and doing the final hook up). The advantage of doing it this way is that it would make for a much neater installation and save two spaces in your house panel that could be used for other things.

Good luck and have fun.

Joe

 

[Farwell]

The smaller the number the bigger the wire until you hit #0 then the zeros are used. Example: #0 #00 #000. The more zeros the bigger the wire.
I use aluminum for out door wiring but never use it for any in wall wiring. Like Eddie said if you use it, either get devices designed for aluminum or use the anti corrosive coating stuff.
Farwell

 

[gates]

Buckcreek,
Be sure to allow for voltage drop at that distance. Assuming you are talking about 240volt single phase, #2 copper at 300 feet is ~ 5% voltage drop. I do not know what your state design requirements are. 3% is the typical design.

Ron

 

[Keoke]

Hi folks, aluminium wire "has a high flow rate under compression". Which means, as others have mentioned, that the tie point screws need to be checked from time to time.

 

[chim]

Copper cable is rarely used for residential services in this area. In the larger sizes, it is pretty trouble free. The biggest problems, as others have said, come from terminating it in lugs / screws that are intended for copper only.

There are a number of names for the compound that should be used when terminating it. Penetrox, CU/AL Aid, NoAlox, and others. Home Depot carries it. It's handy stuff to have. I use it on the terminals of vehicle batteries.............chim

 

[drzmatt]

Running #2 Al 300 feet for 100 amps will have way too much voltage drop. Use the link below to figure out your wire size.



http://www.electrician.com/vd_calculator.html