Split phase motor drum switch wiring help please.

HarryJM

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My Burke #4 came with a split phase motor that I have disassembled/cleaned up and verified that forward and reverse (reversing Red start and Black power cord) work. Although I plan on replace this with a 3 phase/VFD setup I would still like to understand the drum switch wiring for the split phase motor that I have.

The top part of my chicken scratch drawing is the motor wiring for forward (left) and reverse (right). The bottom are the drum switch contacts. The schematic connection diagram is from the Logan Online store.

So do I have the schematic terminals numbered correctly in the bottom half of my chicken scratch drawing? And if so what are the connections for the plug wires and motor wires?

I'm sure the answer is very simple although my brain cannot see it this point.
20200612_150844.jpg20200612_151638 flipped.jpgInkedreversing-drum-switch-11 from logan_LI fixed.jpg
 
Hi Harry- basically to reverse the motor either the run winding(s) or the start winding wires are swapped. The single phase Furnas pictorial shows the run winding being swapped. Unfortunately the presence of a thermal cutout often complicates things. Can you post some additional info on the motor itself? Pictures? Is there a start capacitor? Is this going to run on 120 volts or 240?
-Mark
 
Hi Harry- basically to reverse the motor either the run winding(s) or the start winding wires are swapped. The single phase Furnas pictorial shows the run winding being swapped. Unfortunately the presence of a thermal cutout often complicates things. Can you post some additional info on the motor itself? Pictures? Is there a start capacitor? Is this going to run on 120 volts or 240?
-Mark
No capacitor as the motor is a split phase motor (resistance start motor) and I already have figured out the internal wiring to switch direction per my chicken scratch drawing (right side shows the leads for reverse vs left side). FYI - I used my ohm meter to determine the run vs start winding.

120 volts. I'm just trying to figure out the drum switch wiring at this point.
20200607_133632.jpg
 
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I'll have to study this for a while- not sure if I see both ends of the start winding yet. The G from the thermal cutout might be one end
 
I'll have to study this for a while- not sure if I see both ends of the start winding yet. The G from the thermal cutout might be one end

With the wires disconnected from their post.
The R-S (red starter) wire on post 4 and the B-S (black starter) wire on post L2 have winding resistance of 9 ohm. I have reversed the R-S and B-S and the motor runs in reverse of original connections.
The O-R (orange run) wire on post 4 and Y-R (yellow run) wire on post L2 have winding resistance of 3 ohm. No change made here for reverse running.
For a split phase motor you can disconnect the starter wires, turn the motor on and turn the shaft in either direction to get it to rotate forward or reverse.
 
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OK that helps, let me see if I can come up with a sketch
-M
 
The drum switch diagram you drew looks different from anything I've seen- It doesn't seem to match the diagram you got from Logan
I would check that again
Usually those Furnas drum switches are one of two types:
Drumstyles1.jpeg
 
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I also have two Logan lather (200 and 820) and the previous pictured drum switch is from my 200 and the below pic is from my 820. They are the same and the 820 has the same wiring diagram as the one I got from the Logan web site. The 820 also has the name Furnas at the bottom of the switch. I really appreciate you effort as I have drawn out various scenarios trying to get my brain wrapped around the six different connection points and I have not found one that will switch the two different start wires (R-S and B-S ).
20200613_131845 flipped 820a.jpg
 
The big secret is, there aren't many clear diagrams that show the exact connections when dealing with motors that have three-wire thermal protectors, at least not that I'm aware of. Not much standardization either, amongst motor manufacturers. Looks like your drum switches are what I call the "chopstick" style.
I working on a sketch for you, should be done tonite or tomorrow sometime.
-Mark
 
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The big secret is, there aren't many clear diagrams that show the exact connections when dealing with motors that have three-wire thermal protectors, at least not that I'm aware of. Not much standardization either, amongst motor manufacturers. Looks like your drum switches are what I call the "chopstick" style.
I working on a sketch for you, should be done tonite or tomorrow sometime.
-Mark
Thanks and I really appreciate your effort on this.
 
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