subpannel in house

[jason lambert]

I was out of breakers on my 200 amp service in the house and had a electrision add a 100 amp subpanel in my wiring closet. Thinking now I should of put it in the gurage. Anyhow he used alumin wire to connect the two. Is this normal and safe? I thought you where not suppose to use alumin and copper was better. When I asked him he said alumin is what they use.

[Jack Porter]

I was going to have this done, how much did it run you? If you don't mind me asking.

[jason lambert]

I got a bunch of est. I paid about $800 but also need ground rods driven and my sub panel was next to my fuse box so it was easy to mount and short run of wire. The further it was away the more in $$$ for wire and labor. Just the box ran between $450 - $600.

[Jack Porter]

thanks for the info

[Jeffrey Makiel]

I believe most service wire (i.e., the big stuff) is aluminum now in days. The guage of aluminum wire is sized larger since it's not as good a conductor as copper. Using copper for individual circuits still seems the most common but may change if copper material keeps going up.

Connecting copper to aluminum conductor requires special precautions but I believe should be avoided if possible.

I'm not an electrician and could be wrong or out dated. Perhaps others can chime in.

-Jeff :)

[Rick Christopherson]

Aluminum is typically used for larger conductors simply because it is cheaper. With your panel so close to the original it wouldn't have mattered, but he probably didn't have any copper on hand.
I paid about $800 but also need ground rods driven and my sub panel was next to my fuse box .....Why did you need ground rods for a subpanel right next to your main panel? This sounds really odd, unless the existing panel was not up to current code.

[jason lambert]

Thinking about adding another inthe gurage about 75' away since I found out the 18" bandsaw I am looking at needs 220 :\ What should I use there. Is alumin still ok?

[alex grams]

Jason, the type of wire will not matter so much as what size you need it for and how large of a panel you plan on running with it. Copper prices have gone way up recently, making aluminum more economical. I am sure you could run either copper or aluminum, but aluminum will need to be a larger gauge wire to transmit the same current that a comparably smaller copper wire could. Just make sure whatever size wire you run that you have a breaker on the main panel that trips below the current rating of the wire.

Also, there are plenty of other codes to consider for your application, especially if you are running the wire underground.

[Wade Lippman]

Copper is much preferred, but aluminum is okay in large gauges if everything is approved for it and antioxidant is used. Aluminum is NOT okay in small gauges.
Aluminum is rather cheaper, so it is widely used despite being inferior.

I keep meaning to replace the aluminum cables going to my stove and dryer, but it would be expensive and they haven't failed in 25 years...

[Chris Padilla]

Along with the anti-oxidant goop, be sure the Al is torqued appropriately. It has a larger coefficeint of (linear thermal) expansion over copper and you don't want it working loose over time (23 vs. 17 so it isn't a huge difference). As a reference, mercury is 60 and diamond is 1...concrete is 12, iron or steel is 11.

[Joe Chritz]

Generally speaking with the price of copper what it is any large wire is now done in AL.

The wires coming into you main panel are almost certainly AL. My subpanel in the detached shop is AL, the one in the basement was run with copper. When I put the shop in I couldn't find the copper 4 wire to run even if I wanted to.

Joe