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3 MAJOR POSITIONING CONTROL
3.1 Outline of Major Positioning Controls
Positioning control method when the control unit is set to "degree"
■
Absolute system (When the software stroke limit is invalid)
Positioning is carried out in the nearest direction to the designated address, using the current value as a reference. (This is
called "shortcut control".)
Ex.
1) Positioning is carried out in a clockwise direction when the current value is moved from 315
to 45
.
2) Positioning is carried out in a counterclockwise direction when the current value is moved from 45
to 315
.
To designate the positioning direction (not carrying out the shortcut control), the shortcut control is invalidated and positioning
in a designated direction is carried out by the "[Cd.40] ABS direction in degrees".
This function can perform only when the software stroke limit is invalid. When the software stroke limit is valid, the error
"Illegal setting of ABS direction in unit of degree" (error code: 19A5H) occurs and positioning is not started.
To designate the movement direction in the ABS control, a "1" or "2" is written to the "[Cd.40] ABS direction in degrees" of the
buffer memory (initial value: 0).
The value written to the "[Cd.40] ABS direction in degrees" becomes valid only when the positioning control is started.
In the continuous positioning control and continuous path control, the operation is continued with the setting set at the time of
start even if the setting is changed during the operation.
n: Axis No. - 1
■
Absolute system (When the software stroke limit is valid)
The positioning is carried out in a clockwise/counterclockwise direction depending on the software stroke limit range setting
method.
Because of this, positioning with "shortcut control" may not be possible.
Ex.
When the current value is moved from 0
to 315
, positioning is carried out in the clockwise direction if the software stroke
limit lower limit value is 0
and the upper limit value is 345
.
Positioning addresses are within a range of 0
to 359.99999
.
Use the incremental system to carry out positioning of one rotation or more.
Name
Function
Buffer memory address
Initial
value
[Cd.40]
ABS direction
in degrees
The ABS movement direction in the
unit of degree is designated.
0: Shortcut (direction setting invalid)
1: ABS
clockwise
2: ABS
counterclockwise
4350+100n
0
315
°
45
°
2) Moved from 45° to 315°
315
°
45
°
1) Moved from 315° to 45°
0
°
345.00000
°
315.00000
°
Positioning carried out in the clockwise direction.
Summary of Contents for RD77MS16
Page 1: ...MELSEC iQ R Simple Motion Module User s Manual Application RD77MS2 RD77MS4 RD77MS8 RD77MS16 ...
Page 2: ......
Page 316: ...314 9 COMMON FUNCTIONS 9 4 External Input Signal Select Function Program example ...
Page 317: ...9 COMMON FUNCTIONS 9 4 External Input Signal Select Function 315 9 ...
Page 575: ...13 PROGRAMMING 13 4 Positioning Program Examples 573 13 Error reset program Axis stop program ...
Page 643: ......