SO I just finished rebuilding a commercially sold phase converter. I will not name the manufacture to protect the fact someone else may have been in the unit at some point. This is a 3 HP RPC with a shaftless motor running one start cap, one run cap, a potential relay and a toggle switch controlled 2 position contactor to power the unit up. It had been taken apart by the previous owner and connected to a 5 HP motor so again, someone didn't know what they were doing. The run cap was wired from L1 to L3 (generated leg) and was 78uF. Now based on the 10 to 12 uF per horsepower, this was too big even for the 5 HP but on the 3 HP it made the no load generated leg voltage 275 volts. This is what happens when you guess at what you are doing. Had this been connected to sensitive equipment it would have sent the expensive smoke rolling out of the cabinet for sure. Once I got done I got the following voltages. L1 to L3 was 236 volts L2 to L3 was 221 volts with an input voltage of 224 The 77Uf cap was replaced with a 30uF cap and everything was right with the world. I still don't like potential relays, but that's what this one has and I left it in place.