66
9.17.4
Position Overflow
For ROTAX® servo motor types and Third Party Rotative
Motors, which are operated e. g. as rotary tables always in
the same direction of rotation, it can occur that the
encoder position reaches very high positive or negative
values
In order to ensure that the position can be continuously
incremented in positive or negative direction, a controlled
overflow mechanism is integrated in XENAX® servo
controller.
The maximum position values correspond to
2
31
-
1 = 2’147’483’647 inc in positive direction and
-2
31
=-
2’147’483’648 inc in negative direction.
The overflow takes place between these two values.
2’147’483’647 <>
-
2’147’483’648
Example: positive overflow
Actual Position: 2’147’483’646 inc
Relative Motion: 10 inc
Motion:
Start
position: 2’147’483’646 inc
2’147’483’647 inc
-
2’147’483’648 inc
-
2’147’483’647 inc
…
Target position: -
2’147’483’640 inc
Example: negative overflow
Actual Position: -
2’147’483’648 inc
Relative Motion: -20 inc
Motion:
Start position:
-
2’147’483’648 inc
2’147’483’647 inc
…
Target position:
2’147’483’629 inc
2
31
-1
inc
-2
31
inc
+1 inc
2
31
-1
inc
-2
31
inc
-1 inc
