YASKAWA SGD7S-1R9D Product Manual page 288

8.6 Autotuning without Host Reference
8.6.5 Troubleshooting Problems in Autotuning without a Host Reference
 When an Error Occurs during Execution of Autotuning without a Host
Reference
The gain adjustments
were not successfully
completed.
An error occurred during
calculation of the
moment of inertia.
Positioning was not
completed within
approximately 10 sec-
onds after position
adjustment was com-
pleted.
 When an Error Occurs during Calculation of Moment of Inertia
The SERVOPACK started calculating the moment of
inertia but the calculation was not completed.
The moment of inertia fluctuated greatly and did not
converge within 10 tries.
Low-frequency vibration was detected.
The torque limit was reached.
Speed control changed to proportional control
during calculation of the moment of inertia.
 Adjustment Results Are Not Satisfactory for Position Control
You may be able to improve the adjustment results by changing the settings of the positioning
completed width (Pn522) and position reference unit (position user unit (2701 hex)).
If satisfactory results are still not possible, adjust the overshoot detection level (Pn561). That
may improve the adjustment results.
• Pn561 = 100% (default setting)
This will allow tuning with overshooting that is equivalent to the positioning completed width.
• Pn561 = 0%
This will allow tuning to be performed without overshooting within the positioning completed
width, but the positioning completed width may be extended.
Pn561
(2561
hex)
8-30
Error
Machine vibration occurs or the posi-
tioning completion signal is not stable
when the Servomotor stops.
Refer to the following section for troubleshooting information.

When an Error Occurs during Calculation of Moment of Inertia on page 8-30
The positioning completed width is too
narrow or proportional control is being
used.
Possible Cause
Overshoot Detection Level
Setting Range Setting Unit
0 to 100
Possible Cause
• Increase the setting of the speed loop gain (Pn100).
• Increase the stroke (travel distance).
Set Pn103 (Moment of Inertia Ratio) from the machine
specifications and specify not estimating the moment
of inertia.
Double the setting of moment of inertia calculation
starting level (Pn324).
• If you are using the torque limit, increase the torque
limit.
• Double the setting of moment of inertia calculation
starting level (Pn324).
Use PI control when calculating the moment of inertia.
Default Setting
1% 100
Corrective Action
• Increase the setting of the positioning
completed width (Pn522).
• Change the mode from 2 to 3.
• If machine vibration occurs, suppress
the vibration with the anti-resonance
control function and the vibration sup-
pression function.
Increase the setting of the positioning
completed width (Pn522).
Corrective Action
Speed Position
When Enabled Classification
Immediately
Torque
Setup