IGBTs , insulated gate bipolar transistors, are changing everything. This machine has the internal intelligence to compensate for power line voltage and has the intelligence to stabilize the arc at the load end.
The Miller phone # seems to be only for getting product info - the same stuff you can d/l from their website.
I called two different local Miller dealers and both assured me the Maxstar 150 would run correctly on 208V.
My customer had only bought the compressor a month ago - and it was still attached to the shipping pallet. The dealer was kind enough to allow him to exchange it for a 3-phase unit.
