YASKAWA SGD7S series Product Manual page 203

9.3 Troubleshooting Based on the Operation and Conditions of the Servomotor
Problem
Servomotor
Does Not
Start
Servomotor
Moves
Instanta-
neously,
and Then
Stops
Servomotor
Speed Is
Unstable
Servomotor
Moves with-
out a Refer-
ence Input
9-50
Possible Cause
A failure occurred in the SER-
VOPACK.
The polarity detection was
not executed.
There is a mistake in the Ser-
vomotor wiring.
There is a mistake in the wir-
ing of the encoder or Serial
Converter Unit.
There is a mistake in the lin-
ear encoder wiring.
The setting of Pn282 (Linear
Encoder Scale Pitch) is not
correct.
The count-up direction of the
linear encoder does not
match the forward direction
of the Moving Coil in the
motor.
Polarity detection was not
performed correctly.
There is a faulty connection
in the Servomotor wiring.
A failure occurred in the SER-
VOPACK.
The count-up direction of the
linear encoder does not
match the forward direction
of the Moving Coil in the
motor.
Polarity detection was not
performed correctly.
Confirmation
–
Check the setting of
Pn080 =n.X (Polar-
ity Sensor Selection).
Check the inputs to the
SV_ON (Servo ON) com-
mand.
Check the wiring.
Check the wiring.
Check the wiring.
Check the setting of
Pn282.
Check the directions.
Check to see if electrical
angle 2 (electrical angle
from polarity origin) at any
position is between ±10°.
The connector connec-
tions for the power line
(U, V, and W phases) and
the encoder or Serial
Converter Unit may be
unstable. Check the wir-
ing.
–
Check the directions.
Check to see if electrical
angle 2 (electrical angle
from polarity origin) at any
position is between ±10°.
Continued from previous page.
Correction Reference
Replace the SERVO-
–
PACK.
Correct the parameter
*
setting.
• If you are using an
incremental linear
encoder, send the
SV_ON command
from the host control-
*
ler.
• If you are using an
absolute linear
encoder, execute
polarity detection.
Wire the Servomotor
–
correctly.
Wire the Serial Con-
–
verter Unit correctly.
Wire the cable cor-
–
rectly.
Correct the setting of
*
Pn282.
Change the setting of
Pn080 = n.X
(Motor Phase
*
Sequence Selection).
Place the linear
encoder and motor in
the same direction.
Correct the settings for
the polarity detection-
–
related parameters.
Tighten any loose ter-
minals or connectors
–
and correct the wiring.
Replace the SERVO-
–
PACK.
Change the setting of
Pn080 = n.X
(Motor Phase
*
Sequence Selection).
Match the linear
encoder direction and
Servomotor direction.
Correct the settings for
the polarity detection-
–
related parameters.
Continued on next page.