Siemens SIMOTION Function Manual page 33

The activation/deactivation times of the TO outputCam are dynamically compensated by
means of the derivative-action times. In this way, output cams are dynamically shifted
depending on the actual velocity.
For example, a valve that should open at 200°, with an activation time of 0.5 s
● Must be controlled at 195° at a velocity of 10°.
● Must be controlled at 190° at a velocity of 20°.
This dynamic shift takes place automatically by means of the Output Cam TO.
Settings for the activation and deactivation times can contain positive or negative values.
A negative activation time must be entered if the output cam is to be switched before the
programmed start of the output cam.
Figure 3-17
Note
The time of output for the output cam in the controller is relevant for calculation of the dynamic
adjustment. If velocity changes up to signal output, these changes are no longer taken into
account.
Dead times, e.g. PROFIBUS DP communication times, output delay times on digital outputs,
etc., are taken into account in the actuation time.
Long actuation times exceeding one modulo cycle may lead to heavy fluctuation of the
switching position of actual value output cams (actual value curve). Here, setpoint output
cams should be used or the actuation time should be considerably less than one modulo
cycle.
The system takes into account the specified actuation times when the output cams are
calculated and managed. The switching positions of the output cams are calculated taking into
account the activation time and deactivation time in relation to the present velocity. If, allowing
for actuation times, the output cam was switched, then the system deems this operation to
have occurred, and it does not switch the output cam again even if any subsequent current
velocity changes occur.
Output Cams and Measuring Inputs
Function Manual, 04/2014
Switching behavior at varying actuation times
Output Cam TO - Part I
3.2 Output cam TO basics
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