
B–63523EN–1/03
9. SPINDLE SPEED FUNCTION
1222
Number Message Contents
749 S–SPINDLE LSI ERROR It is serial communication error while system is executing after power
supply on. Following reasons can be considered.
1) Optical cable connection is fault or cable is not connected or cable
is cut.
2) MAIN CPU board or option 2 board is fault.
3) Spindle amp. printed board is fault.
4) The spindle amplifier is under an abnormal condition. (The SPM in-
dication is A, A1, A2, or the like, depending on the type of the ab-
normality.)
If this alarm occurs when CNC power supply is turned on or when
this alarm can not be cleared even if CNC is reset, turn off the power
supply also turn off the power supply in spindle side.
If the spindle amplifier is under an abnormal condition, check the
SPM indication (A, A1, A2, or the like). Then, refer to the FANUC
SERVO MOTOR ai series MAINTENANCE MANUAL (B–65285EN)
or FANUC SERVO MOTOR a series MAINTENANCE MANUAL
(B–65165E) to solve the problem.
750 SPINDLE SERIAL LINK START
FAULT
This alarm is generated when the spindle control unit is not ready for
starting correctly when the power is turned on in the system with the
serial spindle.
The four reasons can be considered as follows:
1) An improperly connected optic cable, or the spindle control unit’s
power is OFF.
2) When the NC power was turned on under 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 again.
3) Other reasons (improper combination of hardware)
This alarm does not occur after the system including the spindle con-
trol 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.
752 FIRST SPINDLE MODE CHANGE
FAULT
This alarm is generated if the system does not properly terminate a
mode change. The modes include the Cs contouring, spindle position-
ing, rigid tapping, and spindle control modes. The alarm is activated if
the spindle control unit does not respond correctly to the mode change
command issued by the NC.
754 SPINDLE–1 ABNORMAL TORQUE
ALM
Abnormal first spindle motor load has been detected.
762 SECOND SPINDLE MODE
CHANGE FAULT
Refer to alarm No. 752.(For 2nd axis)
764 SPINDLE–2 ABNORMAL TORQUE
ALM
Same as alarm No. 754 (for the second spindle)
772 SPINDLE–3 MODE CHANGE ER-
ROR
Same as alarm No. 752 (for the third spindle)
774 SPINDLE–3 ABNORMAL TORQUE
ALM
Same as alarm No. 754 (for the third spindle)
Alarm and message