I have now been able to run my home built CNC router. I am learning to use Mach 3 and the machine. I loaded the Roadrunner.tap g-code that came with Mach 3 into the machine and without the router powered the program went through the program without issue. I put some material in the machine and set the soft limits to the material and started the program with the router running. About 1/5 of the way through the code the program stops and the reset button is flashing with a message saying "External Estop Requested". None of the limit switches have been triggered. I can turn the router off and can reset the program. Within seconds of turning the router back on the reset light flashes with the same message. This is with no movement of any of the axis.
The diagnostic screen indicates that the e stop switches are not activiated. I can manually trigger the estop ligh ton the diagnostic screen by manipulating any of the switches.
The power cord for the router is no where near any of the wires for the z axis or limit switches, so I don't think it is electrical interference causing the problem. However, since the problem only occurs when the router is powered, I suspect it has to be electrical noise. I have also checked all of the electical controls and none are elevated in temperature.
Does anyone have any suggestions on how to get around the problem?