YASKAWA Sigma-7-Series Product Manual page 100

5.3 Troubleshooting Alarms
Alarm Number:
Alarm Name
A.840:
Encoder Data
Alarm
(Detected at the
encoder.)
A.850:
Encoder Over-
speed
(Detected at the
encoder when
the control power
supply is turned
ON.)
A.860:
Encoder Over-
heated
(Detected at the
encoder.)
5-20
Possible Cause
The encoder malfunc-
–
tioned.
The encoder malfunc-
–
tioned due to noise.
The Servomotor
-1
Check the motor speed
speed was 200 min
when the power supply
or higher when the
is turned ON.
control power supply
was turned ON.
A failure occurred in
–
the encoder.
A failure occurred in
–
the SERVOPACK.
The surrounding air
Measure the surround-
temperature around
ing air temperature
the Servomotor is too
around the Servomotor.
high.
The Servomotor load Use the accumulated
is greater than the load ratio to check the
rated load. load.
A failure occurred in
–
the encoder.
A failure occurred in
–
the SERVOPACK.
Confirmation
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the Servomotor
may be faulty. Replace the
Servomotor.
Correct the wiring around
the encoder by separating
the Encoder Cable from
the Servomotor Main Cir-
cuit Cable or by ground-
ing the encoder.
Reduce the Servomotor
speed to a value less than
200 min
the control power supply.
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the Servomotor
may be faulty. Replace the
Servomotor.
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the SERVOPACK
may be faulty. Replace the
SERVOPACK.
Reduce the surrounding
air temperature of the
Servomotor to 40°C or
less.
Operate the Servo Drive
so that the motor load
remains within the speci-
fied range.
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the Servomotor
may be faulty. Replace the
Servomotor.
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the SERVOPACK
may be faulty. Replace the
SERVOPACK.
Continued from previous page.
Correction Reference
–
–
–
-1
, and turn ON
–
–
–
*1
–
–
Continued on next page.