The explanation came from a Miller Tech Service person who was very nice and willing to listen. I say that because when I initially turned the unit on I was taken aback by the sound it made and I turned the unit off and waited until Monday to call Miller direct. I described everything in detail to him and was assured that this was the "auto-line" feature doing its job. Whatever, I can get used to the noise.
All that said, the machine welds fine (on steel) but I am still fine tuning the AC on Al. I am used to a Lincoln Precision Tig 275 and have yet to be able to weld with the inverter as good as I can on the 275. I finally figured out the setting differences and will try again with the Miller set up like I usually use the Lincoln (as a place to start).
As far as power goes, I live out on 10 acres and get juice from a local co-op. I have no problem running my PT 275, my Cutmaster 50, my powermig 255, and my Champion compressor so I can't imagine why I would have a problem with the Miller (esp. w/the auto-line feature).
The guys at my local welding store are top notch and are setting up a meeting with the Miller rep in a couple of weeks so I will see how that goes before I have a final judgement. Ultimately I will get taken care of.
Kevin Bentz
KB Fabrications