YASKAWA SGD7S-1R9D Product Manual page 508

15.2 Alarm Displays
15.2.2 Troubleshooting Alarms
Alarm Code:
Alarm Name
A.C20:
Phase Detection
Error
A.C21:
Polarity Sensor
Error
C22 hex:
Phase Informa-
tion Disagree-
ment
15-28
Possible Cause
Check the voltage of
The linear encoder
the linear encoder sig-
signal level is too low.
nal.
Check the setting of
The count-up direc-
Pn080 = n.X
tion of the linear
(Motor Phase Sequence
encoder does not
Selection). Check the
match the forward
installation orientation
direction of the Mov-
for the linear encoder
ing Coil in the motor.
and Moving Coil.
The polarity sensor
signal is being –
affected by noise.
The setting of Pn282 Check the setting of
(Linear Encoder Scale Pn282 (Linear Encoder
Pitch) is not correct. Scale Pitch).
The polarity sensor is
protruding from the Check the polarity sen-
Magnetic Way of the sor.
motor.
The polarity sensor is Check the wiring of the
not wired correctly. polarity sensor.
The polarity sensor
–
failed.
The SERVOPACK
phase information is
different from the lin- –
ear encoder phase
information.
Confirmation
Fine-tune the mounting of
the scale head. Or,
replace the linear
encoder.
Change the setting of
Pn080 = n.X.
Correctly reinstall the lin-
ear encoder or Moving
Coil.
Correct the FG wiring.
Implement countermea-
sures against noise for the
polarity sensor wiring.
Check the specifications
of the linear encoder and
set a correct value.
Correctly reinstall the
Moving Coil or Magnetic
Way of the motor.
Correct the wiring of the
polarity sensor.
Replace the polarity sen-
sor.
Perform polarity detec-
tion.
Continued from previous page.
Correction Reference
–
page 5-20
–
page 5-15
–
–
–
page 5-25
Continued on next page.