I have a Faunc 0-MD Mill (Lilian CNC 400) that was just starting a milling cycle and during the G53 Z0., the Z-axis halted suddenly and an alarm 339 Alarm for the Z-Axis SPC was generated. I power cycled the mill, but when I home the Z-axis, it decelerates when the limit switch dog is hit (as it should) and then slowly continues past Z=0.000 and then eventually generates the 530 Z+ over-travel alarm when it travels over the dog -- it seems like the homing signal for Z=0 has been lost.
I checked the encoder cable and the connector was a few threads loose, so I tightened it, power cycled, and still have the same problem.
The 760-762 parameters are all 1000 0100, so the SRFLG (serial pulse coder connected) and the BZAL (do zero reference return) request is set which seems to indicate that all is normal. Parameters 770-772 are all 0 indicating no faults.
This system has the semi-closed loop servos (Model Alpha C6/2000; Part: A06B-0126-B077) which uses the serial pulse coder and type-B axis controller (serial pulse coder connects to the servo amplifier over JF3) and there is just one cable (JS3A) to the axis controller (AXE).
I'll double check the servo tuning screens in the morning and see if I can make sense of the reference position adjustment (section 5.3 of the 61395 maintenance manual), but would really appreciate any insights that people may have!
Thanks,
Eric
Same alarm for different axis in case people are searching for this: 319 (X-axis), 329 (Y-axis), 339 (Z-axis)