Siemens SIMATIC ET 200S Manual page 304

Digital Electronic Modules
Principle
The following figure gives you another graphic illustration of the principle of flutter
monitoring.
Parameter for number of signal changes = 9
Parameter for monitoring window t = x
Process
signal
Detection
Diagnostics
Module diagnosis of incoming
flutter error
= report
Figure 12-2 The principle of flutter monitoring
12-8
3 x monitoring window t = 3x
Module diagnosis of
outgoing flutter error
= reset
ET 200S Distributed I/O System
EWA-4NEB780602402-09