9. ERROR CODE LIST
9.1.9 Serial spindle alarms
Number Message Contents
749 S–SPINDLE LSI
A communication error occurred for the se-
rial spindle. The cause may be the discon-
nection of an cable or the interruption of the
power to the spindle amplifier.
(Note) Unlike spindle alarm No. 750, this
alarm occurs when a serial com-
munication alarm is detected after
the spindle amplifier is normally
750 SPINDLE SERIAL
LINK START FAULT
This alarm is generated when the spindle
control unit is not ready for starting correct-
ly when the power is turned on in the sys-
tem with the serial spindle.
The four reasons can be considered as fol-
1) An improperly connected optic cable,
or the spindle control unit’s power is
2) When the NC power was turned on un-
der alarm conditions other than SU–01
or AL–24 which are shown on the LED
display of the spindle control unit.
In this case, turn the spindle amplifier
power off once and perform startup
3) Other reasons (improper combination
This alarm does not occur after the
system including the spindle control
unit is activated.
4) The second spindle (when SP2, bit 4 of
parameter No. 3701, is 1) is in one of
the above conditions 1) to 3).
See diagnostic display No. 409 for details.
751 FIRST SPINDLE
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 num-
ber). Refer to Subsection 9.1.13. The
alarm number XX is the number indicated
on the spindle amplifier. The CNC holds
this number and displays on the screen.
752 SPINDLE MODE
This alarm is generated if the system does
not properly terminate a mode change.
The modes include the spindle position-
ing, rigid tapping, and spindle control
modes. The alarm is activated if the
spindle control unit does not respond cor-
rectly to the mode change command is-
sued by the NC.
754 SPINDLE ABNORMAL
Abnormal first spindle motor load has been