Siemens S7-300 Operating Instructions Manual page 21

Brake cam track
In order to use track 2 as a brake cam track, interconnect digital input I0.
A positive edge of the I0 signal sets the track flag bit.
The track flag bit is reset again when:
● there is no longer a "1" signal at I0 and afterwards
● the controller has detected a negative edge at the track 2 result signal.
In the example, the track flag bit is reset by a negative edge at cam 3 or 4.
FM 352 electronic cam controller
Operating Instructions, 05/2011, A5E01071724-03
Figure 3-3 Setting a brake cam track
Cam control basics
3.2 Tracks and track result
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