Mitsubishi Electric MELSERVO-J4 Series Instruction Manual page 248

Adjustment procedure of 2 gain adjustment mode
Set the same value in [Pr. PB07 Model loop gain] for the axis used in 2 gain adjustment mode.
Step Operation
1 Set to the auto tuning mode.
2 During operation, increase the response level setting value in [Pr. PA09], and return the setting if
vibration occurs.
3 Check value of the model loop gain and the load to motor inertia ratio in advance.
4 Set the 2 gain adjustment mode 1 ([Pr. PA08]: _ _ _ 0).
5 When the load to motor inertia ratio is different from the design value, select the 2 gain adjustment
mode 2 ([Pr. PA08]: _ _ _ 4) and then set the load to motor inertia ratio manually in [Pr. PB06].
6 Set the model loop gain of all the axes to be interpolated to the same value. At that time, adjust to the
setting value of the axis, which has the smallest model loop gain.
7 Considering the interpolation characteristic and motor status, fine-adjust the model loop gain and
response level setting.
Parameter adjustment
[Pr. PB07 Model loop gain]
This parameter determines the response level of the position control loop. Increasing the value improves trackability to a
position command, but a too high value will make overshoot liable to occur at settling. The droop pulses value is determined
by the following expression.
Number of droop pulses [pulse] =
Position command frequency differs depending on the operation mode.
Rotary servo motor and direct drive motor:
Position command frequency
Servo motor speed [r/min]
=
60
Linear servo motor:
Position command frequency = Speed [mm/s]  Encoder resolution (travel distance per pulse)
6 NORMAL GAIN ADJUSTMENT
246
6.5 2 gain adjustment mode
Position command frequency [pulse/s]
Model loop gain setting
× Encoder resolution (number of pulses per servo motor revolution)
Description
Select the auto tuning mode 1.
Adjustment in auto tuning mode 1
Check the upper setting limits.
Select the 2 gain adjustment mode 1
(interpolation mode).
Check the load to motor inertia ratio.
Set model loop gain.
Fine adjustment