Will this diagram work and provide a safe limit shutdown?
Limit switches are NC. The VFD switch may be an opto-isolated switch that engages free run stop. The idea is that the circuit goes high when any of the limits are overrun as the ground is open. This sends a high to the drivers disable and BoB limit inputs. The momentary limit override switch allows the drivers to engage and drive off the limit, and will illuminate when the circuit goes high. The BoB is a CNC4PC C50; the VFD is an Hitachi WJ200; drivers are Gecko G203V. I was going to use separate home switches in series on a different input pin.
An alternative (addition) to the diagram is to wire the Estop in series and use the dedicated E-stop input pin. I think I like this idea better, but I'm not sure. I would have to hold the limit override in that case to reset/move the machine. Also, my Estop switch is not latching, so I would need to buy a new one or build a latching circuit.
Note that I may do something different with the VFD as I have not yet figured out how I want to control the spindle (Modbus or analog PWM, or even manual otherwise).
Thanks.