FILENAMES: Rotary-3Ph-Converter.gif DESCRIPTION: This is a schematic diagram of a rotary phase converter. Posted by Carl Young . The following description was provided: ================================================================= There is a great deal of info on homemade phase converters available over the internet. But not a lot of wiring schematics available, a least the simple layman's kind, which is what I needed. And that's the purpose of this text and schematic to share with others. DISCLAIMER: I am a novice!!! But it worked for me. Not responsible for a damn thing that happens to you. Not even if your sex life improves, hair grows back on a bald head, cancer - cause you drink a lot of coffee etc., You guys know about the legal mumbo-jumbo. Having the need to build one for myself, and being the first one, and most deffinately a novice at it, I collected as much info as I could. I did have the good fortune to know someone (Andy) who works with industrial wiring, motors, etc, and - if you will - picked his brain on frequent occassions prior to construction. I realized that the first thing to do was to have a working drawing that I could understand. Of course the dwg was reviewed several times by Andy, "Yep, you can do that"; "nope, on this one, not a good idea, instead..." finally a finished working schematic. So, motor and parts in hand (so to speek), tackled this mystical challenge. At first there were several set backs, tried the non starting system type; the motor would, by hand spin freely but just would not kick over and come to full speed. I know there are those without a starting circuit, just could not get this one to work without it, you know - wasn't holding my mouth right or something. Back to the drawing board, a few dollars more, to add the starting circuit, of course I proofed it with my resident expert (which is the schematic listed). It started up just fine, several tweaking's of the cap's, the wild leg (artifical leg) SHOULD NOT GO OVER 240 volts, and now I had a working 3hp balanced rotary converter. Supposedly, the balanced rotary phase converter is the optimum of converters because of the stability of the voltages or something like that. The starter relay is a granger 6X550, it is of the heavy duty version, and if you note that the capacitor voltage goes thru this relay. Well, there was a little difficulty in getting this relay, but finally did. Andy says, why not use a relay for a A/C unit, with the cap AFTER the relay, it will still shut off the current to capacitor and thereby take the starting circuit out, and is readily available from A/C parts vendors. So, the specs of the 6X550 are: GE equiv. FJ3BR3 Pick-Up Volts: 180-160 Drop-Out Volts: 100-70. The local A/C house was kind enough to make a copy of the MARS relay data sheet and it appears that the: Mars No 19165 Mars Model No MARS 165 is the one. Hope this is of some use to those that wish to build there own. Carl Port Arthur, TX