Mitsubishi Electric MR-J4 Instruction Manual page 325

7. SPECIAL ADJUSTMENT FUNCTIONS
(d) Adjusting the lost motion compensation
When protrusions still occur, the compensation is insufficient. Increase the lost motion compensation
by approximately 0.5% until the protrusions are eliminated. When notches occur, the compensation
is excessive. Decrease the lost motion compensation by approximately 0.5% until the notches are
eliminated. Different values can be set as the compensation for each of when the forward rotation
(CCW) switches to the reverse rotation (CW) and when the reverse rotation (CW) switches to the
forward rotation (CCW).
(e) Adjusting the lost motion compensation timing
When the machine has low rigidity, the speed loop gain is set lower than the standard setting value,
or the servo motor is rotating at high speed, quadrant projections may occur behind the quadrant
change points. In this case, you can suppress the quadrant projections by delaying the lost motion
compensation timing with [Pr. PE49 Lost motion compensation timing]. Increase the setting value of
[Pr. PE49] from 0 by approximately 0.5 ms to adjust the compensation timing.
(f) Adjusting the lost motion compensation non-sensitive band
When the lost motion is compensated twice around a quadrant change point, set [Pr. PE50 Lost
motion compensation non-sensitive band]. Increase the setting value so that the lost motion is not
compensated twice. Setting [Pr. PE50] may changes the compensation timing. Adjust the lost motion
compensation timing of (e).
Travel
direction
The locus before compensation
Travel
direction
Before timing delay compensation
Travel
direction
Before timing delay compensation
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Compensation
The locus after compensation
Compensation
After timing delay compensation
Compensation
After timing delay compensation