Siemens SIMATIC PCS 7 Operating Instructions Manual page 22

Flutter monitoring
The flutter monitoring detects signal changes that are unusual in process engineering, for
example when an input signal fluctuates too often between "0" and "1". Flutter monitoring
can be configured for each digital input.
The following figure shows a graphical representation of the principle of flutter monitoring.
● Trigger condition
When the number of configured signal changes is equal to the number of signal changes
of the process signal within the configured monitoring time. After expiry of the monitoring
time, this is restarted with the next signal change.
● Reset condition
The monitoring is reset if there is no signal change within the three-fold monitoring time.
● Error message
Exception_Event FLUTTER_SUPPRESS (group message) signals beginning and end
time of the flutter monitoring.
AddFEM Sequence of Event
Operating Instructions, 03/2016, A5E00075541X-06
Functions of the AddFEM SoE
4.1 Front-end function SoE
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