Hello Found this site might help a few people suffering from hf  estop problems like i'm having at the moment as im useing a hf plasma http://www.randyray.com/tmc/rf_shielding.htm .
I will be doing a lot more grounding which hope fully will cure my problem but just out of curiousity on mach3 in the diagnostic page looking at the pin diagram, when my plasma cut out during a cutting process i see a quick green light flash on the 4th pin from top left
is this pin 4, This is what is triggering my estop any advice is welcome. Hopefully some rf filters and more grounding will help
Thanks in advance