On 11/07/2016 11:04 AM, ethan at 757.org
Hmmm it shouldn't be that hard in this day and age
to come up with
that kind of current assuming switchers would be clean enough. I have
a home use LED video screen I assembled/am finishing from Chinese
modules that runs on 480 amps @ 5vdc, power supplies set me back
maybe $300 or less. Could probably adjust them down or get similar
units or higher quality stuff from surplus (Pioneer Magnetics, etc)
A lot depends on location. If you're out in a rural area and serviced
by a Rural Electric Cooperative (REC), it's pretty easy, although there
are the initial costs for the cable, distribution box and transformer.
Farm equipment such as hay dryers tend to be 440V 3-phase, so it's not
something out of the ordinary.
Similarly, if you've got space in a commercial/industrial section of
town, 3-phase power almost goes along without mention. Office buildings
and warehouses tend to have 3-phase service.
Of course, this is US practice. If you were, say, in Germany, 3-phase
power is pretty standard for residential service--the only concern is
the current-carrying capacity.
But if you're a suburban resident living on Mulberry Street, anything
but single-phase is pretty much out of the question.