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Motor windings at commutator

Motor windings at commutator

Motor windings at commutator

Can you guys tell me how to figure out this wiring problem. Only one bar is disconnected. All others have continuity but I have 3 loose wires. 2 have continuity to each other only, the other has continuity to all the bars. How di I wire this back up?

RE: Motor windings at commutator

Will you take a WAG?
You have one unwired bar and two bars adjacent to the unwired bar. I will call these the adjacent bars.
Start with the third wire that has continuity to all others.
Measure the resistance from the open wire to each of the adjacent bars.
The adjacent bar showing the lower resistance will be wired correctly. Call this adjacent #1
The adjacent bar showing the higher resistance will be missing wire. Call this adjacent #2
The third wire will connect to the open commutator bar.
The two wires with continuity will connect to the open bar and to adjacent #2
Polarity matters. Inject a small current between the commutator bars about 90 degrees away from the open bar.
Check the polarity with a compass.
Or I may have made false assumptions and the solution is something else.
As a double check, one adjacent bar should have only one wire connected instead of two.
Good luck.

"Why not the best?"
Jimmy Carter

RE: Motor windings at commutator

Worked perfect. You are the motor man! thanks

RE: Motor windings at commutator

Thank you very much for the report back and the for the kind words.

"Why not the best?"
Jimmy Carter

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