
9 Troubleshooting
9.1.2 Troubleshooting of Alarms
9-16
A.bF2:
System Alarm 2
A SERVOPACK fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the SERVO-
PACK may be faulty. Replace the
SERVOPACK.
A.bF3
:
System Alarm 3
A SERVOPACK fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the SERVO-
PACK may be faulty. Replace the
SERVOPACK.
A.bF4:
System Alarm 4
A SERVOPACK fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the SERVO-
PACK may be faulty. Replace the
SERVOPACK.
A.C10:
Servo Overrun
Detected
(Detected when the
servomotor power is
ON.)
The order of phases U, V, and W
in the servomotor wiring is incor-
rect.
Check the motor wiring.
Confirm that the servomotor is cor-
rectly wired.
An encoder fault occurred.
−
If the alarm still occurs after turning
the power OFF and then ON again,
even though the servomotor is cor-
rectly wired, the servomotor may be
faulty. Replace the servomotor.
A SERVOPACK fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the SERVO-
PACK may be faulty. Replace the
SERVOPACK.
A.C80:
Absolute Encoder
Clear Error and
Multi-turn Limit Set-
ting Error
An encoder fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the servomotor
may be faulty. Replace the servo-
motor.
A SERVOPACK fault occurred.
−
Turn the power supply to the SER-
VOPACK OFF and ON again. If the
alarm still occurs, the SERVO-
PACK may be faulty. Replace the
SERVOPACK.
A.C90:
Encoder
Communications Error
Contact fault of connector or
incorrect wiring for encoder
cable.
Check the connector contact status
for encoder cable.
Re-insert the connector and confirm
that the encoder is correctly wired.
Cable disconnection for encoder
cable or short-circuit.
Or, incorrect cable impedance.
Check the encoder cable.
Use the cable with the specified rat-
ing.
Corrosion caused by improper
temperature, humidity, or gas,
short-circuit caused by intrusion
of water drops or cutting oil, or
connector contact fault caused by
vibration.
Check the operating environment.
Improve the operating environmen-
tal conditions, and replace the cable.
If the alarm still occurs, replace the
SERVOPACK.
Malfunction caused by noise
interference.
−
Correct the wiring around the
encoder by separating the encoder
cable from the servomotor main cir-
cuit cable or by checking the
grounding and other wiring.
A SERVOPACK fault occurred.
−
Connect the servomotor to another
SERVOPACK, and turn ON the
control power. If no alarm occurs,
the SERVOPACK may be faulty.
Replace the SERVOPACK.
(cont’d)
Alarm Number:
Alarm Name
Cause
Investigative Actions
Corrective Actions