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08-25-2016, 09:23 AM
(This post was last modified: 08-25-2016, 09:24 AM by TDKPE.)
Leads 1-4 are the main winding leads, one pair for each (usually 1 and 2 on one of them, and 3 and 4 on the other). They're wired in parallel right now, and get put in series for 240V. You need to record how they're connected to each other now, and separate them. You have to record the connections because if you reverse a pair, the motor won't run.
Then, find what else is connected to them, and where. Those 'extra' connections will be the start winding, including the centrifugal switch and capacitor. There will be at least two locations where 'extra' leads connect to the numbered leads, or put another way, two of the numbered leads (probably 1 and 2, or 3 and 4) will have additional connections. The start winding is always connected in parallel to one of the two run windings, so you have to find where it's connected to the numbered leads, and reverse those two connections.
Tom
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08-25-2016, 12:19 PM
(This post was last modified: 08-25-2016, 01:21 PM by Roly.)
From the picture it looks like leads 1-4 are soldered to the back of the terminal block which are the running winding leads, the link and bare wire jumper on the front side of the terminal block is where you convert from 120v to 240v the other two wires on the front that come from inside the motor should be for the starting winding. It looks like one of them comes from the centrifugal switch and one comes from the winding. As I see it they have to be the starting winding, which most of the older motors were easily reversible. Roly
Make sure the moveable parts that operate the centrifugal switch move freely and are clean not oily.
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08-25-2016, 01:29 PM
(This post was last modified: 08-25-2016, 01:31 PM by TDKPE.)
(08-25-2016, 12:19 PM)Roly Wrote: . . . the other two wires on the front that come from inside the motor should be for the starting winding. It looks like one of them comes from the centrifugal switch and one comes from the winding. As I see it they have to be the starting winding, which most of the older motors were easily reversible.
And they appear to have red insulation, unlike the main winding insulation. It may be as simple as switching the two red leads with the ring termination, but without seeing it first hand, I'd ring them out first with an ohmmeter to see if they have a different DC resistance (with the capacitor jumpered) than the main run windings.
But it's hard to see in a picture.
Oh, and with the existence of an internal overload relay, there's probably more to it, as only one of the two run windings goes through the heater portion (in 120V configuration), while both are disconnected by it, and in 240V configuration, both run windings go through the heater. So there could be more going on inside that's not easily seen.
Tom
“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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You guys are freaking amazing. While I can handle regular wiring, the knowledge to dissect motor wiring is something else. While I hope I never have a motor issue I'm also glad you guys are around to help.
Kudos!
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Yeah I'm blown away and very thankful for your advice. I've been too busy with regular work to dig into it too much yet. I wanna take it slow and low.
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If you can't reverse it electrically and you really want it reversed, its possible.
Swap the endbells and rotor. You will have to extend the wires to get them to the other side and I know they are brittle. I handled a similar motor by cutting the leads as they exited the windings and soldered new wire to them to run to the other side.. I have done this on several motors.
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That's a good idea and a great worst case scenario.
This entire issue is just due to me wanting the motor to sit in a smaller footprint. Seems silly to go through all this just to improve the design aesthetic of it.
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Normally you always reinstall the end bells on the same end and in the same orientation. We used to always mark the frame and end bells with a center punch so they could be reinstalled the same way. Especially important if sleeve bearings as they wear in. As you say for worst case. Instead I would swap the two (red?) wires with eyelets on the terminal block and plug in. Roly
