Safe way to disable a VFD for tool changing


Hello All,

Just curious if there are any generally accepted ways to "hard" disable a VFD so you can safely perform a manual tool change?

My thoughts were to place a switch on the FWD and REV command inputs. I would disconnect these using the switch when I want to perform a tool change.

Any thoughts?

I've also heard that disconnecting the VFD main power and/or disconnecting the motors three wires was hard on the VFD electronics in the long run (both for different reasons).


MASSO Support
Staff member
Yes disconnecting power or motor is not a good idea. All VFD's have an enable input and this is what should be used to disable the VFD. You can simply wire this input via a switch and your VFD will be disabled. Its also a good idea to wire the same enable signal to the estop also so that in case of an emergency the spindle is stopped.