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Very odd motor windings

Very odd motor windings

Very odd motor windings

(OP)
Hello, all. I've got a 3-phase, dual speed motor that's used to steer a satellite dish. I opened the electrical box of the motor and disconnected all of the wires from house power, so now the 6 winding wires are exposed and floating. (I have another motor to install on the same dish, but I don't have exact documentation for it, and I don't want to smoke it since we just got it back from being repaired...hence why I took the other motor apart to copy the wiring)

The freshly repaired motor has 6 wires in the box, labeled 1-6. 1 has continuity with 4, 2 with 5, and 3 with 6 as expected. So far, so good. Here's where it gets weird. I checked continuity of the other motor (the one that's still on the dish...those wires aren't labeled, but you can still see 3 wires going into the motor in one direction, the other 3 in the other direction, so I suppose we can call these 1-3 and 4-6), but rather than having the same continuity as the repaired motor (1-4, 2-5, 3-6), I'm showing continuity between 1-2-3 and 4-5-6. I checked this a few times just to make sure. Wth????

After chewing on this for a while, I have a question: Is it possible this was built with two separate Y configurations (see the attached drawing)? It's a dual speed motor, would wiring these windings up to have two internal Y configs work? If you switched power on to one set, you'd get half speed, and then full speed with both? I've never seen this before, and I'm not sure it would even work, but it's the only way I can explain that strange continuity.

Thanks for any advice here!

RE: Very odd motor windings

The motor with continuity between 1-4, 2-5, 3-6 has an open winding. You may use this for star/delta starting, but not for two speeds. The other one seems to have two star windings. This might be a two speed winding.

RE: Very odd motor windings

The diagram appears to illustrate a common 4 Pole, Wye Connected, Skip Pole, 2 Circuit winding connection.

Leads in the OP's illustration identified as L1, L2, etc are shown outside the diagram suggesting a six lead motor.

In this instance, the ā€œLā€ leads would be connected internally and brought out as three individual leads L1, L2 and L3.

Both neutral points shown in the OP's diagram can remain separated or tied together as well.

John

RE: Very odd motor windings

Is there any nameplate?
ACW

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