Numbers Missing on wires

[Scoobert]

I had an electric motor given to me it is a 3 phase 3hp 1720 rpm except all the numbers are missing from the wires. How do I determine which wire number (1-9) is which so I can set it up to run 220 again. Without smoking it

Thanks

 

[waross]

Hello Scoobert
Try

three phase induction wye-wye motor
thread237-144439
Also try searching this site.
yours

 

[Scoobert]

Thank you, Thats what I needed.

 

[Scoobert]

I have found the phase wires
1-4,2-5 and 3-6 But how do I detirmine which wire is 7,8 or 9?

 

[powerjunx]

Scoobert, your problem is quite hard.

Nowadays, it would be time consuming if you still rely on old fashion ways, although, its excellent way of finding a solution!

I would suggest to used SURGE/COMPARISON TESTER, since you already have the internal winding of Y, you can connect the remaining leads(7,8,9) in series to the Y winding(L1-L2-L3), then test the polarity reversal.The tester will depicts which winding or phase has a reversed polarity. Do some reconnections, until the waveform is uniform, then try to run the motor on NO-LOAD condition, and measure the currents eventually will be acceptable. Ive done this for several times.

The test is reliable, but it needs an experienced technician to carried out the results..

If you haven't this equipment, do the conventional way.