# Split phase motor drum switch wiring help please.



## HarryJM (Jun 12, 2020)

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.


----------



## markba633csi (Jun 12, 2020)

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


----------



## HarryJM (Jun 12, 2020)

markba633csi said:


> 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.


----------



## markba633csi (Jun 12, 2020)

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


----------



## HarryJM (Jun 12, 2020)

markba633csi said:


> 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.


----------



## markba633csi (Jun 13, 2020)

OK that helps, let me see if I can come up with a sketch
-M


----------



## markba633csi (Jun 13, 2020)

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:


----------



## HarryJM (Jun 13, 2020)

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 ).


----------



## markba633csi (Jun 13, 2020)

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


----------



## HarryJM (Jun 13, 2020)

markba633csi said:


> 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.


----------



## markba633csi (Jun 14, 2020)

Harry I think this has a good chance of working; I had to guess a bit-


----------



## HarryJM (Jun 14, 2020)

markba633csi said:


> Harry I think this has a good chance of working; I had to guess a bit-
> View attachment 327589


I will give this a try sometime today and let you know the results. I did measure the ohm for the cutout and did not make note of it. I though the cutout wire leading to the winding was some kind of heat sensor lead as that wire is a lot small than the other two cutout wires.


----------

