Bruce,
I thought the #2 would work as my calculator came up with 3.56% on an 11 foot distance. But the inverter sure did not like it.
The wire was salvaged from an old arc welder. I don't recall the brand and the cable markings only indicate voltage rating and wire gauge. Thinking real hard it might have been a Century... red like Lincoln and made in USA. Anyhow the 2/0 works like a champ! I'll hang onto the #2 for some lesser demand someday.