Determine voltage of single voltage motor?

[ddickey]

How did you measure? was it 7v everywhere? line to line, phase to ground?

 

[Barncat]

Line to line, all three combinations were close to that.

 

[ddickey]

If you could check phase to ground and it was the same as line to line then you'd know you had a delta wound motor and it would be 240 or 480. More than likely it is.

 

[rabler]

Well I spun it up to about 3750 rpm (based on the pulley sizes on it and my drive motor) and got 7 volts. I guess there isn’t enough magnetism left to generate 230 or 460?

Sorry, should have made this clear earlier. Did you run it with something loaded, or nothing connected? It needs some current path to build up beyond self-excitation, electro-magnets work on current, not voltage. Without a path to build some current flow (through some load), the rotor doesn’t get an induced current, so it never gets started building a real voltage. Long shot that there is enough residual magnetism to start that process, but without a load to act as a current path it is doubly handicapped.

 

[Barncat]

What kind of current path? Like a light bulb that is just wired between 2 wires? Or? And then how to test, remove the load and test voltage between 2 wires?

 

[rabler]

What kind of current path? Like a light bulb that is just wired between 2 wires? Or? And then how to test, remove the load and test voltage between 2 wires?

Yes, like the incadescent light bulb. Ideally 3 bulbs wired to a common center, but you could try one bulb between two wires. Leave them in and measure the voltage across 2 wires. You are basically building a three phase induction generator.