VFD on/off switch questions

Jim, yes you are correct, it is a push -on push-off single phase switch. Does that make a difference as to what MKSJ suggested? If not, I will configure and try out in the morning...

And, MKSJ, if S2 connects to the off button line terminal, is it necessary to connect both the off and on load terminals to com?

Oops, killswitch - just read you post. I think that answers my question. I should go get some three strand wire.

Electrical is fascinating, but not mystrong suit - obviously.

Thanks much!
-Glenn
 
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You are use a single maintained switch in a 3 wire configuration, which would need another momentary switch to make it run. The diagram above might also work, but is not correct for 3 wire. If you are only using the grinder in one direction, then I would use 2 wire control. This means when input 1 (Positive terminal) is connected to the COM (Negative terminal) it completes the circuit and the VFD will run forward, break the connection and it stops. You only need 2 wires, no ground, it is all low voltage DC and almost no current.
View attachment 246074View attachment 246075
When using 2 wire control you need to make the following program changes:
00-02 is set to 1: External Run Stop
03-00 is set to 0: Forward/Stop Command
03-01 is set to 1: Reverse/Stop Command
I’m not understanding the line and the load is this not just a digital input to the drive? I don’t know what drive he has but wouldn’t he need a separate switch to switch forward and reverse? Or would he hit start once for forward and hit it again if he’s wanting to reverse it? Normally on a drive you would give the drive an enable with the start button and give it a Designation of forward or reverse with a forward and reverse switch
 
Well, you would use just one pair of contacts and use the two wire configuration per mkjs.

You would also want to provide another switch for For/Rev.
 
S2 is not used unless you wanted to run the grinder in reverse, which I assume you would not do. So with two wire connect the com to S1 and it will continue to run until you break the connection. If you want reverse, connect com to S2 only and it will run in reverse until the connection is broken. You do not connect both S1 and S2 at the same time to com terminal, the VFD will not run.
 
Hi all, this application is a Baldor pedestal grinder. So just one forward rotation, and one speed. So don't expect to need a for/reverse switch- just a large, easily accessible on/off to replace the tiny micro switch on the VFD.

Glenn
 
S2 is not used unless you wanted to run the grinder in reverse, which I assume you would not do. So with two wire connect the com to S1 and it will continue to run until you break the connection. If you want reverse, connect com to S2 only and it will run in reverse until the connection is broken. You do not connect both S1 and S2 at the same time to com terminal, the VFD will not run.
I get that on the two wire set up he can’t apply voltage to both S1 and S2 at the same time. So if he’s going to change it to the two wire won’t he need a jumper here? Or no?

F6C1FC52-CBAF-4465-8C0E-A9DD2179E0A2.jpeg
 
Well, set up the VFD and parameters per MKSJ photo and post. Switch still doesn't work. :apologize: So still stuck..

-g
 
S2 is not used unless you wanted to run the grinder in reverse, which I assume you would not do. So with two wire connect the com to S1 and it will continue to run until you break the connection. If you want reverse, connect com to S2 only and it will run in reverse until the connection is broken. You do not connect both S1 and S2 at the same time to com terminal, the VFD will not run.

I forgot we were working with a grinder here. :eek:
 
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