YASKAWA SGD7S series Product Manual page 526

12.3 Warning Displays
12.3.2 Troubleshooting Warnings
Warning Number:
Warning Name
A.901:
Position Deviation
Overflow Alarm at
Servo ON
A.910:
Overload (warning
before an A.710 or
A.720 alarm occurs)
A.911:
Vibration
12-50
Possible Cause Confirmation
The position devi-
ation exceeded
the parameter set-
tings (Pn526 ×
–
Pn528/100) when
the servo was
turned ON.
The wiring is not
correct or there is
a faulty contact in Check the wiring.
the motor or
encoder wiring.
Operation was
performed that
Check the motor over-
exceeded the
load characteristics and
overload protec-
Run command.
tion characteris-
tics.
An excessive load
was applied
during operation
Check the operation
because the Ser-
reference and motor
vomotor was not
speed.
driven because of
mechanical prob-
lems.
The overload
Check that the overload
warning level
warning level (Pn52B) is
(Pn52B) is not
suitable.
suitable.
A failure occurred
in the SERVO- –
PACK.
Check for abnormal
Abnormal vibra-
motor noise, and check
tion was detected
the speed and torque
during motor
waveforms during oper-
operation.
ation.
The setting of
Pn103 (Moment of
Inertia Ratio) is Check the moment of
greater than the inertia ratio or mass
actual moment of ratio.
inertia or was
greatly changed.
The vibration
Check that the vibration
detection level
detection level (Pn312
(Pn312 or Pn384)
or Pn384) is suitable.
is not suitable.
Continued from previous page.
Correction
Set the position deviation to
be cleared while the servo is
OFF.
Optimize the setting of
Pn528 (Position Deviation
Overflow Warning Level at
Servo ON).
Make sure that the Servo-
motor and encoder are cor-
rectly wired.
Reconsider the load and
operating conditions. Or,
increase the motor capacity.
Remove the mechanical
problem.
Set a suitable overload
warning level (Pn52B).
The SERVOPACK may be
faulty. Replace the SERVO-
PACK.
Reduce the motor speed.
Or, reduce the servo gain
with custom tuning.
Set Pn103 (Moment of Iner-
tia Ratio) to an appropriate
value.
Set a suitable vibration
detection level (Pn312 or
Pn384).
Continued on next page.
Reference
page 8-10
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–
–
page 5-44
–
page 8-42
page 8-16
page 6-98