Hysteresis
Slight movements of the encoder can result in the position value fluctuating around a certain position. If a start or end position is within the fluctuation range, the corresponding cam and the digital output are switched on and off correspondingly often without using a hysteresis, depending on the effective direction of the cam. The hysteresis prevents these unwanted switching operations.
The hysteresis is a position tolerance within which the position values may vary without changing the switching state of the cam.
Behavior when hysteresis is activated:
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The configured hysteresis width is in effect for all cams.
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The hysteresis range extends in the positive and negative directions around the detected direction reversal point. The hysteresis range thus extends over double the configured hysteresis. The hysteresis limit points represent the hysteresis range spanned by the firmware.
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Changes in direction recognized within the hysteresis are ignored and the switching status of cams is not changed.
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After the hysteresis range is exited, the output is set according to the cam settings.
|
① |
Actual position |
|
② |
Effective position |
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③ |
Effective hysteresis |
The following example shows the effects of the hysteresis on the switching behavior of the cam with positive effective direction. The hysteresis keeps the output stable when the encoder value signals a small direction reversal.
|
① |
Hysteresis range |
|
② |
Encoder value |