Posted by derek [68.122.15.159] on Friday, January 03, 2014 at 22:51:01 :
In Reply to: Re: Voltage Drop Question for Air Compressor posted by jerryinidaho [64.234.49.226] on Friday, January 03, 2014 at 21:23:46 :
I have a 60' run from the main 200A panel to the 100A garage sub panel. I used over sized wire to minimize voltage drop. I wanted to minimize voltage drop at the garage and at a 30A circuit that ran another 50' past the garage. Upgrading the wire at installation was more expensive, but much cheaper than realizing later that I needed to buy another run of more expensive wire after the fact. Calculate the load and amperage for the load first, then calculate the voltage drop second to upgrade the wire. Running a skill saw off the remote 30A panel still dims the lights at start up even with the oversized wiring.
You'll need 4 wires to your new garage panel and at least one, probably two ground rods. Isolate neutral and ground.
Make friends with an electrician. Pay him (maybe her) well. Enjoy the peace of mind because the job meets your cuent and future needs, is safe and up to the latest code. If you befriend the right electrician he will teach you a lot while you work together.