Confused Over Reversing Drum Switch Type

karlsangree

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My 1940's era South Bend heavy 10 lathe came with a Lindell Electric Control Corp model RS-1 drum reversing switch. I want to get a new one but am really confused over what to get. Many sites like Amazon have the correct wiring diagram, but I don't believe the photo of the contacts matches the diagram. I don't know if they have the wrong photo, or if I'm retarded. Both are a distinct possibility. On the Electric Motor Warehouse (EMW) website, they have an RS-1 with the following photos:
RS1_diagram__72323.1435075090.jpgRS-1A_inside__40766.1435075090.jpg

To me... the photo of the switch internals make it look like the contacts connection path would be 2-1-3 and 4-6-5 in one direction, and 1-2-4 and 3-5-6 in the other. This doesn't match the wiring chart which shows 1-2, 3-4, and 5-6 on one direction, and 1-3, 2-4, 5-6 in the other.

Am I going crazy? I called EMW and the woman I spoke with said that's the way it's always been, and added that no one has said anything before now. Amazon has something similar.

My switch:
IMG_1606.JPG
The faceplate says "Lindell Electric Control Corp", 1 HP, 220-550 Volts, Style RS-1
 
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The picture on the upper left shows the connection paths very clearly. In the forward position, 1 and 2 are connected, 3 and 4, and 5 to 6. Switched to reverse, 1 and 3 are connected, 2 and 4 are connected, and 5 and 6 are connected. You can quickly check this with an ohmmeter and make sure the switch matches the diagram. What can be seen in the drum switch picture is consistent with the above.

Study the “three phase“ connection diagram and you can see how two of the three leads are swapped to reverse direction, with the other lead passing through in both positions.
 
What can be seen in the drum switch picture is consistent with the above.
I don't see it... In the manufacturer's photo (top right) it looks like if you throw the switch to the right, the rotary drum will connect contacts 1-2-4 and 3-5-6 as seen in my edited photo below. However, the wiring diagram shows the switch connecting 1-3, 2-4, and 5-6 when thrown right. Am I wrong? The contacts in the photo of the new switch don't match mine at all, but the wiring diagram does.
drum with notations.png
 
There are two main types: I call them "hockey stick" and "chopstick" or 3-phase. The hockey stick one is a bit more common.
Your original one that I did the sketch for is the chopstick or 3-phase type.
That is the type you would want for a replacement for the motor you have. For some motors with thermal cutouts like yours the 3-phase type is best
-M
In the first post above, the diagram is for a chopstick type but the picture is for a hockey stick type
 

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I wouldn't replace that switch.
I would probably dress the contacts and run it for another 20 years
 
-M
In the first post above, the diagram is for a chopstick type but the picture is for a hockey stick type

Yes! that's what I thought. So I'm not going crazy. Thanks Mark!

So I guess I just buy the switch and hope the schematic is correct and the picture is wrong.
 
I wouldn't replace that switch.
I would probably dress the contacts and run it for another 20 years

My current plans are for a complete restoration of the lathe at some point in the future. This would include restoring the drum switch which I believe is original to the machine.

For right now (without going into the gory details) I just want to run the lathe and make some chips before time runs out.
 
You can actually rework those old switches to give more life- on one of my Furnas switches, the fingers were arced so bad they were nearly cut in half. I sweat-soldered some copper strips over the damage to give a fresh contact surface.
Works great! Probably outlive me LOL
-M
 
Just to close out this thread, the photo on the website was incorrect. The wiring diagram was the right one for the switch. It seems as though every site that carries this particular reversing switch (RS-1) like Amazon has the same error... correct diagram, wrong photo.
 
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