I am affiliated with this design.
http://www.metalwebnews.com/howto/phase-converter/phase-converter.html
or
http://www.metalwebnews.com/howto/phase-converter/3-phase.pdf
If the hand-drawn details are a little fuzzy, go over to
http://www.metalworking.com/dropbox/_2002_retired_files/
and scroll down to files beginning with "phase". Right click, save the file to your hard drive, then open and "Insert Picture" into Microsoft Word or Powerpoint for a full-sized image that will fill an 8-1/2 x 11 printed page and hopefully be legible.
The designs aren't there to impress anyone, it's just a confidence builder that anyone with a little craftsman in them can do this...the principles aren't super hard or mysterious.
The info is a little dated, construction was in year 2002. The design uses a timing relay for auto-start whereas many others have used a potential relay for the same function. I have no balancing, the voltages are within 10% and has functioned with near daily use until (and hopefully beyond!) 2006 with zero problems.
I would also like to go back on the statement I made at the time of the article about the pony-motor-started RPCs. I've conversed with many people over the years, and any RPC 10hp or more electrically started is an ideal candidate for a pony motor, because it reduces the large ampacity one must account for with electrical "inrush" starting from a dead-stop. ALso this would remove the need for starting capacitors (a fair bank of them for a large RPC). I would simply direct-couple the large 3phase motor to a small single-phase motor of roughly 1/2hp. Run the small motor for a time period enough to attain full speed, then switch the 220v power to the 3phase motor, switch off the single phase motor if desired or simply let it run.
I may eventually undertake this direct-coupled design, for now it's just a recommendation.
