How To One VFD, 3 grinders, rotary changeover switch help

BentRivers

BentRivers

Knifemaker / Craftsman / Service Provider
Joined
Feb 15, 2023
Messages
16
Hello, I'm hoping to get some help with setting up three identical motors on one VFD. I recently bought this switch but the wiring diagram is throwing me for a loop and I cant seem to wrap my head around it.

Ive seen a few other posts on here recommending these switches but not many on how the wiring is done, I have very little experience with electrical but I was able to get my first grinder and vfd set up.... just barely, any help would be greatly appreciated!

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I'm sorry to say your switch is not appropriate for your 3 phase application. It's only capable of switching two legs of the 3 phase power. I hate how the diagram lists 1 pole, 2 pole and 3 pole. It should read Position 1, Position 2 and Position 3.
 
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Thanks Coop. That is how I read the diagram as well. As shown, the switch is a 2-pole, 4-position switch.

Simplest way is to wire two of the standard On-Off-On switches parallel from the VFD. That will run four devices.
Change the numbers on one switch to "3" and "4". This would run four machines. Make sure both are at "0" (OFF) before selecting which machine you want to power.
See images below.

I also found this switch, which could run 3 grinders. It has 5 sets of contacts per position. You could wire the work light or water pump to the extra terminals. Search ebay for "Baomain Universal Rotary Changeover Switch". The only thing I don't like about it is you are sending power to the other machines as you rotate the switch. If everything is off, no issue, but if not .... accidents can happen. A master three pole switch in the line from the VFD would be wise. If you choose this switch, I can give you the wiring diagram for the connections to the grinders. I put images below.


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Thanks you two, that's what was confusing me. The other thread had a solution for an ON OFF ON style switch with the correct 3 pole wiring. I should be able to make some progress now, much appreciated!
 
I only searched Amazon and could not find a correct rotary switch that didn't have a off position when going between multiple 4 positions with one being off. IF it was me I'd install two switches like the first switch Stacy showed. Like he said you would have to make sure both are in the off Position before selecting appropriate motor Position.
 
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LCoop said:
I only searched Amazon and could not find a correct rotary switch that didn't have a off position when going between multiple positions. IF it was me I'd install two switches like the first switch Stacy showed. Like he said you would have to make sure both are in the off Position before selecting appropriate motor Position.
Click to expand...
I think that's what ill do, that seems like the easiest path.
 
I use plugs to connect the motors to the switch, that way if I need to change the motor I don't have to open up the switch and rewire it again,
 
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