Continuous Operation To Torque Control Mode (Ct) - Mitsubishi Electric MELSERVO-J5 User Manual

Continuous operation to torque control mode (ct)

Restrictions
The following functions are not available in the continuous operation to torque control mode. Therefore, if an alarm occurs, the
servo motor will stop using the method DB or EDB, or coast.
• Base circuit shut-off delay time function
• Forced stop deceleration function
• Vertical axis freefall prevention function
• Auto tuning function
• Vibration suppression control 1, 2
• Slight vibration suppression control
• One-touch tuning
• Quick tuning function
Precautions
The relation between the setting value of the command torque and the servo motor torque generation direction can be
changed with the setting values of [Pr. PA14 Travel direction selection] and [Pr. PC29.3 Torque POL reflection selection].
The servo motor outputs the torque calculated by adding up the command torque and the value set in [Pr. PE47 Unbalanced
torque offset].
In the continuous operation to torque control mode, the response to the torque command is affected. Do not set servo
parameters as shown below.
• [Pr. PB12 Overshoot amount compensation] is set to a value other than "0".
• [Pr. PB24.1 PI-PID switching control selection] is set to "3".
Behavior
For details, refer to each controller manual.
■Parameter adjustment method
When using the continuous operation to torque control mode, adjust parameters using the following steps.
1.
Adjusting servo stability
Adjust servo stability so that the operation is performed normally without vibration in the position mode or speed mode.
2.
Setting the torque feedback gain
Restore the value of [Pr. PB03 Torque feedback loop gain] to the initial value.
3.
Adjusting the torque feedback gain
If the servo motor speed or torque fluctuates when a workpiece comes into contact with a target object, decrease the value of
[Pr. PB03]. Decreasing the value of [Pr. PB03] will help suppress fluctuation in servo motor speed or torque when a workpiece
comes into contact with a target object. However, doing so will decrease trackability to the command torque.
2 CONTROL MODE
91
2.2 Control mode [B]
2