What's new
What's new

Hurco BMC 4020/HT Axis X faults


Aug 30, 2017
Hi All,

I'm working again on a Hurco BMC 4020/HT milling machine, but now there are some AXIS X faults:

- When I am running "CALIBRATE MACHINE" function for the first time after powering up, it shows me a message "UNEXPECTED LIMIT SWITCH DETECTED ON AXIS X". To "solve" the problem I have to run "RESET SERVOS AND SPINDLE" function and run "CALIBRATE MACHINE" function again. The toolmaker that runs this milling machine every day is complaining that this not supposed to happen.

- Many times during milling process, machine is showing "FOLLOWING ERROR ON AXIS X" and stops in a FAULT condition. This was not happening before.

Inside electrical cabinet there are some SIEMENS SIMODRIVE 611 drives, some of them with no HMI. I'm quite concerned about "playing around" with some of those closed loop control parameters to try fixing those issues. They were working fine since a long time ago and I'm not sure that there is a problem there.

Have anyone had this type of issues before?
I do not know, again, where to look now.
I'd appreciate if anybody could give some advise to me where I'm supposed to look for.

Thanks in advance,