BAD CRASH

[dawizard]

I installed an mpu11 running mach3 on a bed mill over 1 year ago and it's been running fine up till now. While running a proven program the Z axis rammed into a part. For some unknown reason the mill skipped drilling 1 hole out of a 9 hole pattern, then when the program ended with g91,g28z0 it rammed the tool into the part at full rapid. My best guess would be corrupted data for some reason. Shouldn't the machine have locked up if that where the case. Why did it take off like it was possessed. Is this a problem with mach? I don't need a machine that I can't trust. Do I need to switch to another control software?

[AjaxTech]

It could have been cause by noise in the encoder lines for that axis and it put the system in a Runaway condition. I would check the encoder and the encoder signal wires for that axis.

[dawizard]

The encoder was purchased from ajax. The wiring is shielded with the shielding grounded on the motor side only. Noise was my first thought also, but have already double checked the encoder leads. The strange thing was it missing a hole but continuing to drill the remaining holes as if nothing happened. Out of a 9 hole pattern it skipped the 2nd hole. It was a proven program that had ran several parts before. I have been using nc's for 30 years and have never had a machine do that before. It has ran daily for over a year without any major problems and has ran without any problems since. I know mach3 can be a little buggy. Could a glitch from mach3 have caused both of the problems?

[Centroid_Tech]

Dawizard,

We always connect the encoder cable shield at the motion card side not the motor side but as long as your motors are properly grounded to chassis ground you should be ok.

Really cannot speak for the Mach3 software as it is not our software. If you want to try different control software you can opt to buy the Centroid software. It is very user friendly and has it's own conversational programming.

It can be ordered here: http://www.ajaxcnc.com/ajax-cnc-components/