
APPENDIX
B–63124EN/01
G. ALARM LIST
703
9) Servo alarms
Number Message Contents
400 SERVO ALARM: n–TH AXIS OVER-
LOAD
The n–th axis (axis 1 to 8) overload signal is on. Refer to diagnosis dis-
play No. 201 for details.
401 SERVO ALARM: n–TH AXIS VRDY
OFF
The n–th axis (axis 1 to 8) servo amplifier READY signal (DRDY) went
off.
404 SERVO ALARM: n–TH AXIS VRDY
ON
Even though the n–th axis (axis 1 to 8) READY signal (MCON) went off,
the servo amplifier READY signal (DRDY) is still on. Or, when the power
was turned on, DRDY went on even though MCON was off.
Check that the servo interface module and servo amp are connected.
405 SERVO ALARM: (ZERO POINT RE-
TURN FAULT)
Position control system fault. Due to an NC or servo system fault in the
reference position return, there is the possibility that reference position
return could not be executed correctly. Try again from the manual refer-
ence position return.
407 SERVO ALARM: EXCESS ERROR The difference in synchronous axis position deviation exceeded the set
value.
410 SERVO ALARM: n–TH AXIS – EX-
CESS ERROR
The position deviation value when the n–th axis (axis 1 to 8) stops is
larger than the set value.
Note) Limit value must be set to parameter No.1829 for each axis.
411 SERVO ALARM: n–TH AXIS – EX-
CESS ERROR
The position deviation value when the n–th axis (axis 1 to 8) moves is
larger than the set value.
Note) Limit value must be set to parameter No.1828 for each axis.
413 SERVO ALARM: n–th AXIS – LSI
OVERFLOW
The contents of the error register for the n–th axis (axis 1 to 8) are be-
yond the range of –2
31
to 2
31
. This error usually occurs as the result of
an improperly set parameters.
414 SERVO ALARM: n–TH AXIS –
DETECTION RELATED ERROR
N–th axis (axis 1 to 8) digital servo system fault. Refer to diagnosis dis-
play No. 200 and No.204 for details.
415 SERVO ALARM: n–TH AXIS – EX-
CESS SHIFT
A speed higher than 511875 units/s was attempted to be set in the n–th
axis (axis 1 to 8). This error occurs as the result of improperly set CMR.
416 SERVO ALARM: n–TH AXIS – DIS-
CONNECTION
Position detection system fault in the n–th axis (axis 1 to 8) pulse coder
(disconnection alarm). Refer to diagnosis display No. 201 for details.
417 SERVO ALARM: n–TH AXIS – PA-
RAMETER INCORRECT
This alarm occurs when the n–th axis (axis 1 to 8) is in one of the condi-
tions listed below. (Digital servo system alarm)
1) The value set in Parameter No. 2020 (motor form) is out of the
specified limit.
2) A proper value (111 or –111) is not set in parameter No.2022
(motor revolution direction).
3) Illegal data (a value below 0, etc.) was set in parameter No. 2023
(number of speed feedback pulses per motor revolution).
4) Illegal data (a value below 0, etc.) was set in parameter No. 2024
(number of position feedback pulses per motor revolution).
5) Parameters No. 2084 and No. 2085 (flexible field gear rate) have
not been set.
6) A value outside the limit of {1 to the number of control axes} or
a non–continuous value (Parameter 1023 (servo axis number) con
tains a value out of the range from 1 to the number of axes, or an
isolated value (for example, 4 not prceded by 3).was set in parame
ter No. 1023 (servo axisnumber).
420 SERVO ALARM: n AXIS SYNC
TORQUE
(M series)
During simple synchronous control, the difference between the torque
commands for the master and slave axes exceeded the value set in pa-
rameter No. 2031.
421 SERVO ALARM: n AXIS EXCESS
ER (D)
The difference between the errors in the semi–closed loop and closed
loop has become excessive during dual position feedback. Check the
values of the dual position conversion coefficients in parameters No.
2078 and 2079.