Anybody ever heard of "Unique 3 Phase"?

[Barncat]

Even without an oscilloscope, I think it is possible to figure out phase lags using voltmeter relative to a temporary artificial measurement "ground" made from three equal value resistors with a common middle connected to real earth. Choose values which will not get smoking hot! It is just a measurement. 1mA or or so is enough. This in addition to measuring floating voltages phase to phase. It does involve then drawing phase diagrams triangles to discover the phase angle lags.

The same 3-resistor trick can let you use a 2-Channel oscilloscope. Make any one phase the "reference", and then check the second and third phases relative to it. This is what my mind is telling me. Properly, I should be trying it out before I write such stuff, but I don't have one of those around. It is what I fully expect to happen if I were to try it.

Building things from schematics is close to my ceiling at this point. Checking phase angles with a volt meter would require a lot of research, that may need to wait a few years based on current project list. I am just happy I got it to work. I have a large jointer and large planer that both have 3 phase motors, I have transformers and capacitors, so at this point I am just going to build a couple of these “auto transformer converters” for those two wood working machines so they can go in my wood shop and leave the metal shop where the RPC is stationed (two separate small buildings).

 

[graham-xrf]

Building things from schematics is close to my ceiling at this point. Checking phase angles with a volt meter would require a lot of research, that may need to wait a few years based on current project list. I am just happy I got it to work. I have a large jointer and large planer that both have 3 phase motors, I have transformers and capacitors, so at this point I am just going to build a couple of these “auto transformer converters” for those two wood working machines so they can go in my wood shop and leave the metal shop where the RPC is stationed (two separate small buildings).

I think what you did, and where you went with this is just great! Getting into the exactness of discovering phase angle lags, whether by oscilloscope, or voltmeters and reference phase resistors is for teaching and designing, and maybe diagnosing a total stoppage.

That you can make the blades spin with enough power to work, without burning up the stuff, is all you need.