YASKAWA SGD7S Product Manual page 528

Problem Possible Cause
There is a SERVOPACK
pulse counting error due to
noise.
Absolute
Encoder
The encoder was subjected
Position
to excessive vibration or
Deviation
shock.
Error (The
position
that was
saved in the
host con-
A failure occurred in the
troller when
encoder.
the power
A failure occurred in the
was turned
SERVOPACK.
OFF is dif-
ferent from
the posi-
tion when
the power
was next
Host Controller Multiturn
turned ON.)
Data or Absolute Encoder
Position Data Reading Error
12.4 Troubleshooting Based on the Operation and Conditions of the Servomotor
Confirmation
Check to see if there is
noise interference on the
I/O signal line from the
encoder or Serial Con-
verter Unit.
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
Implement counter-
measures against noise
for the encoder or
–
Serial Converter Unit
wiring.
Reduce machine vibra-
tion. Improve the
mounting state of the
–
Servomotor or linear
encoder.
Replace the Servomo-
–
tor or linear encoder.
Replace the SERVO-
–
PACK.
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.
12
12-59