YASKAWA JUSP-MD D01A Series User Manual page 305

9 Troubleshooting
9.1.2 Troubleshooting of Alarms
Alarm Number:
Alarm Name
(Alarm Description)
A.C10:
Servo Overrun
Detected
(Detected when the
servomotor power is
ON.)
A.C80:
Absolute Encoder
Clear Error and
Multi-turn Limit Set-
ting Error
A.C90:
Encoder
Communications Error
A.C91:
Encoder
Communications
Position Data Error
9-16
Cause
The order of phases U, V, and W
in the servomotor wiring is incor-
rect.
An encoder fault occurred.
A fault occurred in the multi-
winding drive unit, SERVO-
PACK, or converter.
An encoder fault occurred.
A fault occurred in the multi-
winding drive unit.
Contact fault of connector or
incorrect wiring for encoder
cable.
Cable disconnection for encoder
cable or short-circuit.
Or, incorrect cable impedance.
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.
Malfunction caused by noise
interference.
A fault occurred in the multi-
winding drive unit.
Noise interference occurred on
the I/O signal line because the
encoder cable is bent and the
sheath is damaged.
The encoder cable is bundled
with a high-current line or near a
high-current line.
The FG potential varies because
of influence from machines on
the servomotor side, such as the
welder.
Investigative Actions
Check the motor wiring.
−
−
−
−
Check the connector contact status
for encoder cable.
Check the encoder cable.
Check the operating environment.
−
−
Check the encoder cable and con-
nector.
Check the cable layout for encoder
cable.
Check the cable layout for encoder
cable.
(cont'd)
Corrective Actions
Confirm that the servomotor is cor-
rectly wired.
If the alarm still occurs after turning
the control power supply OFF and
ON again even though the servomo-
tor is correctly wired, the servomo-
tor may be faulty. Replace the
servomotor.
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the multi-winding drive
unit, SERVOPACK or converter
may be faulty. Replace the multi-
winding drive unit, SERVOPACK,
or converter.
Turn the control power supply OFF
and ON again. If the alarm still
occurs, the servomotor may be
faulty. Replace the servomotor.
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.
Re-insert the connector and confirm
that the encoder is correctly wired.
Use the cable with the specified rat-
ing.
Improve the operating environmen-
tal conditions, and replace the cable.
If the alarm still occurs, replace the
multi-winding drive unit.
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.
Connect the servomotor to another
multi-winding drive unit, and turn
ON the control power supply. If no
alarm occurs, the multi-winding
drive unit may be faulty. Replace
the multi-winding drive unit.
Confirm that there is no problem
with the cable layout.
Confirm that there is no surge volt-
age on the cable.
Properly ground the machines to
separate from the encoder FG.