YASKAWA SGD7S - Page 528

12.4 Troubleshooting Based on the Operation and Conditions of the Servomotor
12-59
12
Maintenance
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.)
There is a SERVOPACK
pulse counting error due to
noise.
Check to see if there is
noise interference on the
I/O signal line from the
encoder or Serial Con-
verter Unit.
Implement counter-
measures against noise
for the encoder or
Serial Converter Unit
wiring.
–
The encoder was subjected
to excessive vibration or
shock.
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).
Reduce machine vibra-
tion. Improve the
mounting state of the
Servomotor or linear
encoder.
–
A failure occurred in the
encoder.
–
Replace the Servomo-
tor or linear encoder.
–
A failure occurred in the
SERVOPACK.
–
Replace the SERVO-
PACK.
–
Host Controller Multiturn
Data or Absolute Encoder
Position Data Reading Error
Check the error detec-
tion section of the host
controller.
Correct the error detec-
tion section of the host
controller.
–
Check to see if the host
controller is executing
data parity checks.
Perform parity checks
for the multiturn data or
absolute encoder posi-
tion data.
–
Check for noise interfer-
ence in the cable
between the SERVO-
PACK and the host con-
troller.
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.
Continued from previous page.
Problem Possible Cause Confirmation Correction Reference