Chapter 9 Unbalanced Torque Offset; Setting Unbalanced Torque Offset; Automatic Setting; Manual Setting - Mitsubishi Electric MR-J5 User Manual

9
UNBALANCED TORQUE OFFSET
For a vertical axis, the effects of gravity cause unbalanced torque. Therefore, the vertical axis may fall slightly immediately
after servo-on. To prevent the vertical axis from falling, the unbalanced torque of a machine can be set as an unbalanced
torque offset to cancel the unbalanced torque. For machines where unbalanced torque does not occur, setting the unbalanced
torque offset is unnecessary.
9.1

Setting unbalanced torque offset

Set the unbalanced torque offset using the following procedure.

Automatic setting

1.
Servo parameter setting
Set [Pr. PE41.6 Unbalanced torque offset setting selection] to "1" (automatic setting).
2.
Estimating friction
Complete friction estimation for both the forward and reverse rotations.
For the procedure of friction estimation, refer to "Vibration estimation function" in the following manual.
MR-J5 User's Manual (Function)
Once friction estimation is complete for both the forward and reverse rotations, the value of [Pr. PE47 Unbalanced torque
offset] will be set automatically according to the estimated friction value.

Manual setting

1.
Servo parameter setting
Set [Pr. PE41.6 Unbalanced torque offset setting selection] to "0" (manual setting).
2.
Measure the torque
Use MR Configurator2 to measure the torque in the forward direction feed and reverse direction feed.
3.
Setting an unbalanced torque offset
Calculate unbalanced torque from the measurement result of the torque, then set the unbalanced torque value in [Pr. PE47
Unbalanced torque offset].
Unbalanced torque [%] =
9 UNBALANCED TORQUE OFFSET
108
9.1 Setting unbalanced torque offset
(Torque in forward direction feed [%]) + (Torque in reverse direction feed [%])
2