Specifications

Examples and tips
PROGRAMMING MANUAL 241
Revision 5.0
Example 6
fig. 24
The mechanical system consists of a ball screw. It uses a servo motor with a
17-bit absolute encoder. The mechanical gear ratio of the gearbox is 1:3.
The screw pitch of the ball screw is 10mm per revolution. The total travel
distance of the ball screw is 540 mm. The mechanical measurement units
must be mm.
With the same procedure as in example 1, we have:
Therefore:
One solution is:
The calculation of the multiturn limit setting parameter Pn205 is not needed
in this case because the ball screw is a system with a fixed (limited) axis. It is
enough to set this value large enough to have the overflow of the counter out
of the effective position. Also, because of the axis is finite, it is not important
to set the REP_OPTION parameter, because REP_DIST must be set large
enough so it is outside of the maximum effective position (540 mm). One
solution is: REP_DIST = 1000 and REP_OPTION = 0.
With these setting, executing MOVE(17) moves the ball screw 17 mm in
forward direction.
17-bit absolute
encoder
M
1:3 Gear
10mm
540mm
Pn202
Pn203
UNITS =
2
17
encoder_counts
1 motor_revolution
1 ballscrew_revolution
3 motor_revolution
10mm
1 ballscrew_revolution
10
2
17
3 encoder_counts
=
mm
=
.
.
..
.
.
Pn202
Pn203
UNITS
17
= 2
10
3
17
= 2
2 5
3
16
= 2
5
3
.
UNITS = 2 = 65536
16
Pn202 = 3
Pn203 = 5