YASKAWA SGD7S series Product Manual page 359

8.5 Estimating the Moment of Inertia
8.5.4 Operating Procedure
 Help Button
Click this button to display guidelines for setting the reference conditions. Make the fol-
lowing settings as required.
• Operate the motor to measure the load moment of inertia of the machine in comparison
• Set the operation mode, reference pattern (maximum acceleration rate, maximum
• Correct measurement of the moment of inertia ratio may not be possible depending on
 Reference Selection Area
Either select the reference pattern for estimation processing from the box, or set the val-
ues in the Detailed Setting Group. Generally speaking, the larger the maximum acceler-
ation rate is, the more accurate the moment of inertia estimation will be.
Set the maximum acceleration range within the possible range of movement considering
the gear ratio, e.g., the pulley diameters or ball screw pitch.
 Confirm Button
Click this button to display the Reference Confirmation Dialog Box.
 Detailed Setting Area
You can change the settings by moving the bars or directly inputting the settings to cre-
ate the required reference pattern.
 Next Button
Click this button to display the Reference Transmission Dialog Box.
 Cancel Button
Click this button to return to the Tuning Dialog Box.
Information
6.
Click the Next Button.
The Reference Transmission Dialog Box will be displayed.
8-20
with the rotor moment of inertia.
speed, and maximum travel distance), and speed loop-related parameters.
the settings. Set suitable settings using the measurement results as reference.
 The travel distance is the distance for one operation in the forward or reverse direction.
During multiple operations, the operation starting position may move in one direction or the
other. Confirm the possible operating range for each measurement or operation.
 Depending on the parameter settings and the moment of inertia of the machine, overshoot-
ing and undershooting may occur and may cause the maximum speed setting to be
exceeded temporarily. Allow sufficient leeway in the settings.
When Measurement Is Not Correct
Estimating the moment of inertia ratio cannot be performed correctly if the torque limit is
activated. Adjust the limits or reduce the acceleration rate in the reference selection so
that the torque limit is not activated.
CAUTION