9 Troubleshooting
9.1.2 Troubleshooting of Alarms
9-14
A.830:
Absolute Encoder
Battery Error
(The absolute encoder
battery voltage is lower
than the specified value.)
The battery connection is incor-
rect.
Check the battery connection.
Reconnect the battery.
The battery voltage is lower than
the specified value 2.7 V.
Measure the battery voltage.
Replace the battery.
A fault occurred in the multi-
winding drive unit.
−
The multi-winding drive unit may
be faulty. Replace the multi-wind-
ing drive unit.
A.840:
Encoder Data Error
(Detected on the encoder
side.)
An encoder malfunctioned.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the servomotor may be
faulty. Replace the servomotor.
Malfunction of encoder because
of noise interference, etc.
−
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.850:
Encoder Overspeed
(Detected when the con-
trol power supply was
turned ON.)
(Detected on the encoder
side.)
The servomotor speed is higher
than 200 min
-1
when the control
power supply was turned ON.
Check the motor rotating speed
(Un000) to confirm the servomotor
speed when the power is turned ON.
Reduce the servomotor speed to a
value less than 200 min
-1
, and turn
ON the control power supply.
An encoder fault occurred.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the servomotor may be
faulty. Replace the servomotor.
A fault occurred in the multi-
winding drive unit.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the multi-winding drive unit
may be faulty. Replace the multi-
winding drive unit.
A.860:
Encoder Overheated
(Only when an absolute
encoder is connected.)
(Detected on the encoder
side.)
The ambient operating tempera-
ture around the servomotor is too
high.
Measure the ambient operating tem-
perature around the servomotor.
The ambient operating temperature
must be 40
°
C or less.
The motor load is greater than the
rated load.
Check the accumulated load ratio
(Un009) to see the load.
The motor load must be within the
specified range.
An encoder fault occurred.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the servomotor may be
faulty. Replace the servomotor.
A fault occurred in the multi-
winding drive unit.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the multi-winding drive unit
may be faulty. Replace the multi-
winding drive unit.
A.b10:
Speed Reference A/D
Error
(Detected when the
servo is ON.)
A malfunction occurred in the
speed reference input section.
−
Clear and reset the alarm and restart
the operation.
A fault occurred in the SERVO-
PACK.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the SERVOPACK may be
faulty. Replace the SERVOPACK.
A.b11:
Speed Reference A/D
Data Error
A malfunction occurred in the
speed reference input section.
−
Clear and reset the alarm and restart
the operation.
A fault occurred in the SERVO-
PACK.
−
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the SERVOPACK may be
faulty. Replace the SERVOPACK.
(cont’d)
Alarm Number:
Alarm Name
(Alarm Description)
Cause
Investigative Actions
Corrective Actions