YASKAWA SGD7S-1R9D Product Manual page 538

15.4 Troubleshooting Based on the Operation and Conditions of the Servomotor
Problem
Absolute
Encoder
Position
Deviation
Error (The
position
that was
saved in the
host con-
troller when
the power
was turned
OFF is dif-
ferent from
the posi-
tion when
the power
was next
turned ON.)
15-58
Possible Cause
The encoder was subjected
to excessive vibration or
shock.
A failure occurred in the
encoder.
A failure occurred in the SER-
VOPACK.
Host controller multiturn data
or absolute encoder position
data reading error
Confirmation
Turn OFF the Servo Sys-
tem. Check to see if
vibration from the
machine occurred.
Check the Servomotor
installation (mounting sur-
face precision, securing
state, and alignment).
Check the linear encoder
installation (mounting sur-
face precision and secur-
ing method).
–
–
Check the error detec-
tion section of the host
controller.
Check to see if the host
controller is executing
data parity checks.
Check for noise interfer-
ence in the cable
between the SERVO-
PACK and the host con-
troller.
Continued from previous page.
Correction Reference
Reduce machine vibra-
tion. Improve the
mounting state of the
–
Servomotor or linear
encoder.
Turn OFF the Servo
System. Replace the
–
Servomotor or linear
encoder.
Turn OFF the Servo
System. Replace the
–
SERVOPACK.
Correct the error detec-
tion section of the host
–
controller.
Perform parity checks
for the multiturn data or
–
absolute encoder posi-
tion data.
Implement counter-
measures against noise
and then perform parity
checks again for the
–
multiturn data or abso-
lute encoder position
data.
Continued on next page.