Fanuc Troubleshooting Alarm SP0976 SP0978 SP0979

Fanuc Series 15i 150i

Fanuc Alarm SP0976 SP0978 SP0979

Fanuc Alarm SP0976 (Serial Spindle Communication Control Error)
Fanuc Alarm SP0978 (Serial Spindle Communication Control Error)
Fanuc Alarm SP0979 (Serial Spindle Communication Control Error)

An abnormality occurred during the control of communication between the CNC and a serial spindle.

Cause and Action

If an alarm other than AL–24 is issued for the serial spindle amplifier, turn off the spindle amplifier, then turn on the CNC again.
In all other cases, check whether the serial spindle is connected.
(1) Is the serial spindle amplifier powered?
(2) Is the cable to the serial spindle attached to the correct connector?
(3) Is the cable to the serial spindle broken?
If the above checks do not reveal any abnormality, the printed circuit board in the CNC or the spindle amplifier may be defective.