Motor Connections and Identification

Hi, not sure why you have the 3rd pair of leads but the flying leads must go to neutral Does the rating plate show more than one voltage? Regards chas

Thanks for your reply, there is no rating plate on the motor or any information available hence my query.

regards

Rob

For what I can see looks like a dual voltage (Would be 120/240 in Canada) capacitor start motor with the run windings hooked up in series for the higher voltage.

If you take the leak hooked up to the capacitor and measure to the other leads (not the leads in the connector you should read continuity with a reasonable resistance to one of them. This would be your start winding leads. The remaining 2 unconnected leads should have continuity with a lower resistance and should also have continuity to the wires in the connector with about 1/2 the resistance on the two previous leads.

As elsewhere stated, looks like a standard dual-voltage (120/240) 1Ø cap-start arrangement. A big question is: "Was the motor running properly with this particular configuration , previously...?"

The 2 leads tied-together appear as though it is putting the run windings in series for the higher voltage operation. This leaves you a 4-lead connection-configuration:

#4 (left-to-right, on your sketch) is clearly one end of the "Start" winding. Your multimeter will tell you which (of the others) is the other end.

The problem, as I see it (someone correct me if I've forgotten too much of what I knew, 20+ years ago!) , is that motors of this style, with 6 leads, is represented by the added schematic above-right.

For 120v operation, the run windings are paralleled and the start winding connects directly across the runs (paralleled with them; reversing the 2 start leads is all it takes to reverse the motor's rotation). This would be 3 leads to line, 3 to neutral.

For 240v operation, the run windings get connected in series, and one end of the "Start" winding must be connected at that union (thus "center-tapped") as well. [This would be the "connector" on your sketch]

In this configuration (for 240v operation), you have only one end of your "Start" winding to connect to line. Connecting it to one side of your supply provides one direction of rotation; connecting it to the OTHER side of your supply provides opposite direction of rotation.

Set yourself up with a "current-limiting-test-bench" (several 100 watt bulbs paralleled on your "test-leads") and ... after preliminary checks with your multimeter ... attempt to hook it up for 120v operation, and verify which leads(/windings) are which.

Once you have verified which lead is which (in "safe mode") ... THEN you can easily connect properly for the higher voltage operation.

For more feedback, please "scrounge" to provide more info...(!)

Best Wishes ~

Many thanks for your replies and your valuable assistance.

regards