Mitsubishi MELDAS HS Series User Manual

Chapter 8 Adjustment
8–18
8-3-4 Improvement of protrusion at quadrant changeover
The response delay (caused by non-sensitive band from friction, torsion, expansion/contraction,
backlash, etc.) caused when the machine advance direction reverses is compensated with the lost
motion compensation function.
With this, the protrusions that occur with the quadrant changeover in the DDB measurement method,
or the streaks that occur when the quadrant changes during circular cutting can be improved.
Circle cutting path before compensation Circle cutting path after compensation
(1) Lost motion compensation (LMC)
The lost motion compensation compensates the response delay during the reversal by adding the
torque command set with the parameters when the speed direction changes. There are two
methods for lost motion compensation. With the intelligent servomotor, type 2 is used as a
standard.
(The explanation for type 1 method is omitted because it is interchangeable with the old method.)
<Setting method>
1) Set the special servo function selection 1 (SSF1) bit 9. (The LMC type 2 will start).
2) Set the compensation amount with a stall % (rated current % for the general-purpose motor) unit
in the lost motion compensation 1 (LMC1). The LMC1 setting value will be used for
compensation in the positive and negative directions when LMC2 is 0.
3) If the compensation amount is to be changed in the direction to be compensated, set LMC2. The
compensation direction setting will be as shown below with the CW/CCW setting. If only one
direction is to be compensated, set the side not to be compensated as –1.
No. Abbrev. Parameter name Explanation
SV027 SSF1 The lost motion compensation starts with the following parameter. Special servo function
selection 1
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
aflt zrn2 ovs2 ovs1 lmc2 lmc1 vfct2 vfct1
bit No LMC LMC type 1 LMC type 2
Setting
prohibited.
8 lmc1 0 1 0 1
9 lmc2 0 0 1 1
No. Abbrev.
Parameter
name
Unit Explanation Setting range
SV016 LMC1 Lost motion
compensation 1
Stall % (rated
current %)
While measuring the quadrant protrusion amount, adjust with a
5% unit.
The ± direction setting value will be applied when LMC2 is set to
0.
–1 to 200
SV041 LMC2 Lost motion
compensation 2
Stall % (rated
current %)
Set 0 as a standard.
Set this when the compensation amount is to be changed
according to the direction.
–1 to 200
Compensation
Cutting
direction
Compensation
point
CW CCW
A X axis: LMC2 X axis: LMC1
B Y axis: LMC1 Y axis: LMC2
C X axis: LMC1 X axis: LMC2
D Y axis: LMC2 Y axis: LMC1
+Y
-Y
+X
-X
A
The X axis command direc-
tion changes from + to –.
D
The Y axis command direc-
tion changes from + to –.
B
The Y axis command direc-
tion changes from – to +.
C
The X axis command direc-
tion changes from – to +.

Mitsubishi MELDAS HS Series Specifications

General

Brand	Mitsubishi
Model	MELDAS HS Series
Category	Servo Drives
Language	English