Fanuc alarm: 751 - FIRST SPINDLE ALARM DETECTION(AL-XX)

This alarm indicates in the NC that an alarm is generated in the spindle
unit of the system with the serial spindle. The alarm is displayed in form
AL-XX (XX is a number). Refer to 2.3 or 2.4 Alarms displayed on
spindle servo unit .The alarm number XX is the number indicated on
the spindle amplifier. The CNC holds this number and displays on the
screen.