I have my cnc machine running on a g540. Connected to input 4 is my touch plate which connects with a single wire to an aluminum block.

I have had no issues with the setup until today, all of a sudden Mach 3 will not sense the touching of the router bit to the block.

I have checked the wire and it is fine, If I measure the voltage between the block and the router bit, it measures 11.5v. All other input pins work properly with the proximity sensors.

I have changed out the g540 with a spare unit and that did not seem to change anything either.

I am looking for some input on this situation? Could I have accidentally hit something in Mach3?

Thank you for any help.

BenG
Kansas City