Craftsman 1hp 115/220 6 wire motor

[invisabledog]

This motor came with my South Bend lathe. It was wired for 220v 1ph. The po stated that he went to turn it on one day and the magic smoke came forth and it just hummed. I took it apart and found the wire labled 2a not connected to anything. I'm thinking it came loose from the reset button. I need to put some shrink tubing on all the leads as the insulation is brittle. I also need to know how to rewire it. I tested the leads and found the pairs. This was run thru a drum switch so it had reverse. I don't have the remains of the original wiring, but I can get pics of the drum switch.

 

[mattthemuppet2]

from what I've read (so take this with a pinch of salt), the start windings (1 pair) will have a slightly different resistance to the run windings, say in the order of an ohm difference or less. The run windings are run in parallel for 110V and series for 220V. The start winding poles are reversed, once the motor stops and the centrifugal switch re-engages, to change direction but the run windings stay the say (which is why changing direction of the start windings before the motor stops won't change the direction of the motor).

When I was looking into this to troubleshoot my Atlas motor, I found a bunch of wiring diagrams to help wire up a drum switch.

Hopefully that clarifies more than confuses and fingers crossed someone with more knowledge and experience will chime in soon!

 

[invisabledog]

from what I've read (so take this with a pinch of salt), the start windings (1 pair) will have a slightly different resistance to the run windings, say in the order of an ohm difference or less. The run windings are run in parallel for 110V and series for 220V. The start winding poles are reversed, once the motor stops and the centrifugal switch re-engages, to change direction but the run windings stay the say (which is why changing direction of the start windings before the motor stops won't change the direction of the motor).

When I was looking into this to troubleshoot my Atlas motor, I found a bunch of wiring diagrams to help wire up a drum switch.

Hopefully that clarifies more than confuses and fingers crossed someone with more knowledge and experience will chime in soon!

I did notice different resistance in the pair marked 3a/3b.

 

[UncleRuss]

You must also get the direction of currant flow correct in the run windings. If the motor just hums on start, they are opposing each other. Reverse the connections on one set of wires and that should correct the problem. The winding pair with the higher resistance is the start winding and should hook up in series with the capacitor and centrifugal switch.

Have fun!!!!!

 

[invisabledog]

When I took this motor apart the wire labeled 2A was not attached to anything. It looks like I have 2 options. It either went to the reset button or the contact on the starter switch. Unfortunately I can't tell. There is currently only 1 wire going to the reset and 2 coming out. The starter switch also has only one wire. I'm stumped.

 

[eded59]

Maybe this will help.
The centrifugal switch should be in series between the starting cap and start winding.
Probably should test the cap while it's apart.

 

[invisabledog]

There is no capacitor in this motor. Doesn't appear it ever had one.

 

[John Hasler]

There is no capacitor in this motor. Doesn't appear it ever had one.

It's induction start. Relies on the difference in resistance of the windings to produce the phase shift necessary for starting. Doesn't produce as much starting torque as a capacitor-start motor but it's simpler and more reliable.

 

[eded59]

if it's the start winding that's bad or disconnected you will be able to spin the motor by hand in either direction and turn it on and it will take off. Of the six leads you should have three windings, two will have the same resistance and the one that's different is the start winding. Non of the leads should have any continuity to the frame of the motor...

 

[invisabledog]

As stated above. I do have three windings with one having different resistance. When I opened the motor up, the wire labeled 2a was not connected to anything. I need to know what that needs connected to. Also I only have one wire coming from the start switch. Last but not least, the reset button has one wire going in and two coming out. I have continuity from the incoming wire to both leads out, is this correct? That doesn't sound right to me.