In article .com, " wrote:
I am trying to find out the wire sizes needed for a 250' underground
feeder from the main panel, to a sub panel in the garage. I would like
a 220, 50 or 60 amp service.

At that distance, for the neutral and the two hot conductors, minimum of 6AWG
copper for 50A or 4AWG copper for 60A, and for the ground, minimum of 8AWG
copper at either 50A or 60A.

Grounding requirements are different in subpanels. You must make sure that:
- the subpanel has two separate bars for ground and neutral
- the two bars are NOT connected to each other (they ARE in the main)
- the neutral bar is insulated from the panel chassis
- the ground bar is NOT insulated from the panel chassis

You may also need a separate ground rod at the garage; check with your local
building inspector.

What type wire would be the least expensive/

You'll need to make a few phone calls to find that out.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.