Yaskawa Sigma II Series DC Power Input SGMAJ User Manual
Page 288

10.1 Troubleshooting
10-7
10
A.51
Overspeed
(Detected when 
the feedback 
speed is the max-
imum motor 
speed
Occurred when the 
control power sup-
ply was turned ON. 
A SERVOPACK board fault occurred.
Replace the SERVOPACK.
Occurred when 
servo was ON. 
The order of phases U, V, and W in the servomotor 
wiring is incorrect.
Correct the servomotor wiring.
The encoder wiring is incorrect.
Correct the encoder wiring.
Malfunction occurred due to noise interference in 
the encoder wiring.
Take measures against noise for the encoder wir-
ing.
A SERVOPACK fault occurred.
Replace the SERVOPACK.
Occurred when the 
servomotor started 
running or in a 
high-speed rotation.
The order of phases U, V, and W in the servomotor 
wiring is incorrect.
Correct the servomotor wiring.
The encoder wiring is incorrect.
Correct the encoder wiring.
Malfunction occurred due to noise interference in 
the encoder wiring.
Take measures against noise for the encoder wir-
ing.
The position or speed reference input is too large.
Reduce the reference value.
The setting of the reference input gain is incorrect.
Correct the reference input gain setting.
A SERVOPACK board fault occurred.
Replace the SERVOPACK.
A.71
A.72
A.71: High Load
A.72: Low Load
Occurred when the 
control power sup-
ply was turned ON. 
A SERVOPACK board fault occurred.
Replace the SERVOPACK.
Occurred when the 
servo was ON.
The servomotor wiring is incorrect or the connection 
is faulty.
Correct the servomotor wiring.
The encoder wiring is incorrect or the connection is 
faulty. 
Correct the encoder wiring.
A SERVOPACK fault occurred.
Replace the SERVOPACK.
Occurred when the 
servomotor did not 
run by the refer-
ence input.
The servomotor wiring is incorrect or the connection 
is faulty.
Correct the servomotor wiring.
The encoder wiring is incorrect or the connection is 
faulty.
Correct the encoder wiring.
The starting torque exceeds the maximum torque.
Reconsider the load and operation conditions, or 
reconsider the servomotor capacity.
A SERVOPACK fault occurred.
Replace the SERVOPACK.
Occurred during 
normal operation. 
The actual torque exceeds the rated torque or the 
starting torque largely exceeds the rated torque.
Reconsider the load and operation conditions, or 
reconsider the servomotor capacity.
Temperature in the SERVOPACK panel is high.
Reduce the in-panel temperature to 40
°C or less.
A SERVOPACK fault occurred.
Replace the SERVOPACK.
A.73
Dynamic Brake 
Overload
Occurred when the 
control power sup-
ply was turned ON. 
A SERVOPACK board fault occurred.
Replace the SERVOPACK.
Occurred when the 
servomotor was 
running and in a sta-
tus other than servo 
OFF. 
A SERVOPACK board fault occurred.
Replace the SERVOPACK.
Occurred when the 
servomotor was 
running in servo 
OFF status.
The rotating energy at a DB stop exceeds the DB 
resistance capacity.
cReduce the motor speed,
dReduce the load moment of inertia, or 
eReduce the number of times of the DB stop 
operation.
A SERVOPACK fault occurred.
Replace the SERVOPACK.
Table 10.3 Alarm Display and Troubleshooting (cont’d)
Alarm
Display
Alarm Name
Situation at Alarm
Occurrence
Cause
Corrective Actions
