User Manual
  Application examples 
  13.1 Examples of EMERGENCY STOP shutdown applications 
SIRIUS ACT 3SU1 pushbuttons and signaling devices 
System Manual, 02/2015, A5E03457306020A/RS-AB/002 
267 
Configuration 
Figure 13-2  Emergency stop shutdown via AS-i to SIL 3 or PL e with a Modular Safety System 
Operating principle 
The Modular Safety System monitors each of the 
two
-channel emergency stop devices connected to 
AS
-i. When one of the emergency stop devices is 
actuated, the Modular Safety System opens the 
enabling circuits and switches the power conta
c
tors 
off in a safety
-related way. If the emergency stop 
device is unlatched and the feedback circuit is 
closed, the Start button can be used to switch on 
again.










