Easy as PI . The ST15 is a single phase generator synchronous . I drive it at a steady 60 HZ and maintain a load on it of about 5- 10 kw with the irrigation pumps, lighting, air conditioning, Hot water, cooking etc, . when the wife wants to do some laundry, usually while I am welding ( she's allergic to clothes lines) we need a bit more power.
I spin up the Baldor 20 Hp 3 ph with the Metro 6/1 to 3600 Rpm and then close the breaker to the panel, The current flow is nill until I begin to over drive the Baldor, at about 3608 rpm the current flow reverses and the baldor becomes a generator and puts a load on the Lister, I only have one leg (2 line out of the three) attached to 2 legs of the single phase 110/220 (use 2- 20 amp breakers just like in a normal 220 v circuit)
I don't close the breaker until I am at the 3600 rpm speed or the baldor wants to act like a motor and draws current from my grid, once I push it above 3600 the current reverses and it becomes a generator albeit not quite as efficient as a single phase motor would be..
The St15 acts like a voltage regulator and a HZ regulator putting the additional current into my "grid" .
Caution, I have to monitor constantly whilein this configuration, because if the Lister allows the speed of the Baldor to go lower than 3600, it begins to draw massive amounts of power from my grid and a three phase motor trying to run on one phase pulls plenty of power, thus the 20 amp breakers..
The other 2 legs of the baldor have voltage available but are three phase configuration, and will draw down my 6/1 too much so I haven't tapped them. I suppose with a larger Prime mover I could set up a full three phase panel..
I have a 10 HP single phase baldor 1800rpm sitting there that I am going to replace the 20 HP 3 phase when I get time to fidle with it I think it will be a bit safer and more efficient. .. It is planting season here and taking all this poor crippled boy's energy.
PS.. I got the 3 phase motor for only $50.00. used 3 phase are dirt cheap, and I needed dirrt cheap.
(Since then I got my tax return and got the high effiency 10 hp Single phase motor (about $300 and should be able to get more usable power from it than a ST10 gen head at lower cost.. it should generate about 39 amps at 230 v (8900 watts) the only drawback is it will not be a stand alone application as it will need an "external grid" to supply the excitation and regulation. ( you also have to remove the starting circuit and a couple of other mods. Utterpower has a book available that will tell you a lot more about this, I suggest that if you are interested inb this type of technology you get this book) . Hope this helps..
Steve