Hysteresis
- Menu: 4.5.3-4.1-4
- Index: 8577.13
Description
If the input value fluctuates around the limit of the cam window, then the switch result and consequently the state of the cam will also fluctuate. To obtain a stable switching signal, a hysteresis value can be assigned to the cam track. This value is used to define a hysteresis window (limit value ± hysteresis value) around the limits of the cam window. The hysteresis becomes active as soon as the limit of the cam window is reached. As long as the actual position is within the hysteresis window, the cam track is not evaluated again.
CW | Cam window |
HW | Hysteresis window |
Actual position | Direction of travel of the cam window | Result bit of the cam track | Description |
|---|---|---|---|
80 | Both directions | 0 | The value is outside the cam window. The switching signal of the cam track is not set. |
90 | Left → right | 0 | The value is outside the cam window. The switching signal of the cam track is not set. |
100 | Left → right | 1 | The value is the lower limit of the cam window. The switching signal of the cam track is set and the hysteresis becomes active. |
90 | Right → left | 1 | The value is within the hysteresis window that was already activated at actual position 100. The cam track is not evaluated again. The switching signal of the cam track remains set. |
140 | Left → right | 1 | The value is within the cam window. The hysteresis is no longer active. The switching signal of the cam track remains set. |
150 | Left → right | 1 | The value is the upper limit of the cam window. The switching signal of the cam track remains set. |
151 | Left → right | 0 | The cam window is left. The switching signal of the cam track is reset and the hysteresis becomes active. |
130 | Right → left | 0 | The value is within the cam window but the cam window is only activated from the left. This is why the cam track is not evaluated again and the switching signal of the cam track remains reset. |
161 | Both directions | 0 | The value is outside the cam window. The hysteresis is no longer active. The switching signal of the cam track is not set. |
NF | Cam window |
HW | Hysteresis window |
Actual position | Direction of travel of the cam window | Result bit of the cam track | Description |
|---|---|---|---|
80 | Both directions | 0 | The value is outside the cam window. The switching signal of the cam track is not set. |
90 | Left → right | 0 | The value is outside the cam window. The switching signal of the cam track is not set. |
100 | Both directions | 1 | The value is a limit of the cam window. The switching signal of the cam track is set and the hysteresis becomes active. |
90 | Right → left | 1 | The value is within the hysteresis window that was already activated at actual position 100. The cam track is not evaluated again. The switching signal of the cam track remains set. |
111 | Left → right | 1 | The hysteresis is deactivated but the value is within the cam window. The switching signal of the cam track remains set. |
99 | Right → left | 0 | The cam window is left. Since the hysteresis was deactivated, the switching signal of the cam track is reset. The hysteresis was reactivated at 100. |
101 | Left → right | 0 | The hysteresis remains active. The cam track is not evaluated again. The switching signal of the cam track remains reset. |
139 | Both directions | 1 | The hysteresis is left at 110. The value is within the cam window. The switching signal of the cam track is set. |
150 | Left → right | 1 | The value is the upper limit of the cam window. The hysteresis is no longer active. The switching signal of the cam track remains set. |
151 | Left → right | 0 | The cam window is left. The switching signal of the cam track is reset and the hysteresis becomes active. |
140 | Right → left | 0 | The hysteresis remains active. The switching signal of the cam track remains reset. |
161 | Both directions | 0 | The value is outside the cam window. The cam track is not evaluated. The hysteresis is deactivated. |
