Siemens SIRIUS ACT 3SU1 System Manual page 568

Application examples
16.1 Examples of EMERGENCY STOP shutdown applications
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 contactors
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.
Safety-related components
Note
In addition to the safety-related components, operation of an AS-i network requires an AS-i
master and an AS-i power supply.
568
Emergency stop device
3SU1
Modular Safety System
3RK3
SIRIUS ACT 3SU1 pushbuttons and signaling devices
System Manual, 08/2018, A5E03457306020A/RS-AK/010
Contactor
2 x 3RT20