YASKAWA SGD7S-R70A20A023F40B Product Manual page 116

5.1 FT40 Specification
5.1.3 Troubleshooting Alarms
Alarm Number:
Alarm Name
A.C51:
Overtravel
Detected during
Polarity Detection
A.C52:
Polarity Detec-
tion Not Com-
pleted
A.C53:
Out of Range of
Motion for Polar-
ity Detection
A.C54:
Polarity Detec-
tion Failure 2
A.C80:
Encoder Clear
Error or Multiturn
Limit Setting Error
5-28
Possible Cause
The overtravel signal
Check the overtravel
was detected during
position.
polarity detection.
The servo was turned
ON when using an
absolute linear
encoder, Pn587 was
–

set to n. 0 (Do
not detect polarity),
and the polarity had
not been detected.
The travel distance
exceeded the setting
of Pn48E (Polarity
–
Detection Range) in
the middle of detec-
tion.
An external force was
applied to the Servo- –
motor.
A failure occurred in
–
the encoder.
A failure occurred in
–
the SERVOPACK.
Confirmation
Wire the overtravel sig-
nals. Execute polarity
detection at a position
where an overtravel sig-
nal would not be
detected.
When using an absolute
linear encoder, set Pn587

to n.
ity)
Increase the setting of
Pn48E (Polarity Detection
Range). Or, increase the
setting of Pn481 (Polarity
Detection Speed Loop
Gain).
Increase the setting of
Pn495 (Polarity Detection
Confirmation Force Refer-
ence).
Increase the setting of
Pn498 (Polarity Detection
Allowable Error Range).
Increasing the allowable
error will also increase the
motor temperature.
Turn the power supply to
the SERVOPACK OFF and
ON again. If an alarm still
occurs, the Servomotor or
linear encoder may be
faulty. Replace the Servo-
motor or linear encoder.
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
–
1 (Detect polar-
–
–
–
–
Continued on next page.