Westinghouse drum switch on South Bend 10L

Hi, I'm new to the site and hoping someone can help me with wiring this Westinghouse type N140 drum switch so it reverses my Craftsman 3/4 hp single phase cap start motor. I can find absolutely no info on this switch anywhere! I got the lathe in parts and the motor only ran in forward (ccw). Motor has two line connections and a red and black lead that says to swap to change direction. I have done that and the motor does run in (cw) reverse while the handle on the switch is in the forward direction. I have tried many wiring combinations and seen many sparks but no forward and reverse. Not sure how to post pics here but I hope to figure it out.

centsarg said:

Hi, I'm new to the site and hoping someone can help me with wiring this Westinghouse type N140 drum switch so it reverses my Craftsman 3/4 hp single phase cap start motor. I can find absolutely no info on this switch anywhere! I got the lathe in parts and the motor only ran in forward (ccw). Motor has two line connections and a red and black lead that says to swap to change direction. I have done that and the motor does run in (cw) reverse while the handle on the switch is in the forward direction. I have tried many wiring combinations and seen many sparks but no forward and reverse. Not sure how to post pics here but I hope to figure it out.

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Sorry, forgot to mention that I want to run the motor on 115v.

We need to know the switch wiring diagram. If it is not inside the switch cover, you'll have to trace out which terminals are connected when the switch is in each position. With that, we can help you.

allan

IMO you should not use that motor...it is a 3450rpm motor....not a good choice....for as little as 200 bucks you can replace it with a 3ph motor(1200-1800rpm ) and VFD that runs on 115v and will also give you some variable speed flexibility.

Hi kitno455,
Wasn't expecting a response so quickly. No diagram or info of any kind inside switch cover.
FORWARD has continuity between 1 & 2, 3 & 4, 5&6. OFF has no continuity anywhere. REVERSE has continuity between 5 & 6 only, finger 1 no contact, finger 2 contacting pad, finger 3 contacting pad, finger 4 not contacting pad. See [/ATTACH] above for pic of switch in REVERSE position. I'm guessing maybe its a three phase switch?
Thanks for taking time to look at this.
centsarg

Hi iwananew10K,
Thanks for your response, wasn't expecting one so quickly. I always thought it was a little fast for the machine, but I'm no longer a chips fly guy after twenty five years. Slow is more my speed at home. I didn't post it in my first post, but I do have it powered presently with a baldor 1hp 3ph with a TECO vfd. Its stuff I had in the garage and on other projects that I cobbled together when the Craftsman on/off toggle switch went out forcing its removal from under the lathe. This switch and motor I would like to get running together as a backup not having experience with the durability of the vfd. The switch is original with the lathe and it would go with it when the time comes. Honestly, I haven't been able to get it figured out myself and I've been fighting with it for over two weeks. Was hoping someone else had the same switch with a diagram. I replied to Kitno455 with the switch position and continuity info. Hope he can figure it out.
Thanks,
centsarg

That's a goofy switch, and I don't see any way to use it successfully for reversing, single phase or otherwise. If the machine already has a vfd, I would do what it takes to fix that instead.

allan

Hi Allan, Thanks for taking the time to look at my drum switch and motor problem. I will struggle on with it a little while longer. Not willing to give up just yet. Someone else out there has to have the same switch on their S.B. Thanks again.

I think kitno455 is right because to me, the switch looks messed up. You see where the lower left contact is sort of "tall" so that it can bridge the lower and middle fixed contacts? The one on the upper right should also look like that. That configuration makes it possible to hook the start winding up one way for forward operation and the other way for reverse. Without the other "tall" contact, you could not use that switch to start a motor in either direction. Hard to explain what happened to it though.

Dobermann said:

I think kitno455 is right because to me, the switch looks messed up. You see where the lower left contact is sort of "tall" so that it can bridge the lower and middle fixed contacts? The one on the upper right should also look like that. That configuration makes it possible to hook the start winding up one way for forward operation and the other way for reverse. Without the other "tall" contact, you could not use that switch to start a motor in either direction. Hard to explain what happened to it though.

Click to expand...

If someone has had it apart the could have put that one contact on wrong. It looks like the contacts just clamp to the cylinder in the center. Turn the one around .

Hi All, Thanks for your time looking at this problem of mine. I got it solved after I pulled out the big tool in the toolbox. I said, I GIVE UP! I stopped trying to figure out the Westinghouse drum and just used it as a power on contact with neutrals from wall and motor tied together and brought the red and black directional leads through a DPDT back to their terminal lugs and BINGO! CW and CCW as pretty as you please, controlling direction through the DPDT toggle. That's close enough for me. I mapped it all out and put it on the shelf where it will perform back-up duty if the VFD ever goes down. Thanks again for your help and suggestions.

In case anyone else ever stumbles on this thread- the problem here was the switch had some of the brass fingers chopped off- this other thread has pictures of what it should look like: https://www.practicalmachinist.com/...e-n140-drum-switch-about-lose-my-mind-357877/

allan