Remote Emergency Stop Switch for Generator

[WGEC]

I have a few existing generator installations where I need to install a new remote E-Stop switch. A few are Kohler 40kw units with existing E-Stops on the genny itself. Those are easy because the circuit is simply a 2 wire normally closed, that I can extend into the building and terminate to the new switch in series.

Other sites have Generac units with NO existing E-Stop buttons. They have the typical OFF/Manual/AUTO selector switch, and I successfully installed the remote E-Stop button by breaking the wire that comes off of the Auto and Manual terminal on the switch, and running it through the NC contacts on the E Stop. I am wondering if this is the best way to do this?

Alternatively, should I break the control circuit before it enters the selector switch? I tested this, and it does shut down the genny.

What has me concerned is that there is actually a wire from the OFF position terminal on the selector switch, that terminates to a PCB and a terminal strip. So my E Stop button is not exactly duplicating the OFF position of the switch, rather just breaking the ON signal. Is this acceptable to do? What function does this OFF signal have?

Thanks in advance!

 

[ceb58]

I have a few existing generator installations where I need to install a new remote E-Stop switch. A few are Kohler 40kw units with existing E-Stops on the genny itself. Those are easy because the circuit is simply a 2 wire normally closed, that I can extend into the building and terminate to the new switch in series.

Other sites have Generac units with NO existing E-Stop buttons. They have the typical OFF/Manual/AUTO selector switch, and I successfully installed the remote E-Stop button by breaking the wire that comes off of the Auto and Manual terminal on the switch, and running it through the NC contacts on the E Stop. I am wondering if this is the best way to do this?

Alternatively, should I break the control circuit before it enters the selector switch? I tested this, and it does shut down the genny.

What has me concerned is that there is actually a wire from the OFF position terminal on the selector switch, that terminates to a PCB and a terminal strip. So my E Stop button is not exactly duplicating the OFF position of the switch, rather just breaking the ON signal. Is this acceptable to do? What function does this OFF signal have?

Thanks in advance!

What type panel do you have on the generators C,E,H or Nexus?

 

[WGEC]

I believe the Generacs had type C. I am not sure about the others.

 

[hillbilly1]

I wouldn't think it's the Nexus, because the on/off/auto is soldered to a circuit board. I had a job where the Nexus controller would not meet the required time delay. When switched to on, it would immediatley start, but had a long delay on auto. I was going to intercept the "on" control, and use the transfer switch start contact, but was unable to due to that design. Generac could not come up with a controller that would meet the minimum transfer time requirement, so we had to remove it and replace it with a Kohler. (customer supplied, so they were not very happy with Generac)

 

[ceb58]

I believe the Generacs had type C. I am not sure about the others.

My wiring diagrams do not show the E-stop but the units we have do have the E-stop on the control board. If my memory serves me right it is breaking wire #13 coming off of the fuse holder on the front of the panel. You could also break wire #56. That is the + wire feeding the start solenoid.

 

[WGEC]

Yes, I see that on the wiring diagram, thanks. Do you think there would be any issue with circuit length and voltage drop? I used 12 gauge stranded to the remote E Stop, about 100' there and 100' back. I'm not sure how much load would be on either of those wires, and think it's 12 or 24 volts DC.

 

[ceb58]

Yes, I see that on the wiring diagram, thanks. Do you think there would be any issue with circuit length and voltage drop? I used 12 gauge stranded to the remote E Stop, about 100' there and 100' back. I'm not sure how much load would be on either of those wires, and think it's 12 or 24 volts DC.

I dont think it would be an issue.