Startup Testing; Connection Of Actuators - Siemens SIRIUS 3SK1 Manual

4.3.12

Startup testing

The sensor or protection equipment must be opened and closed again after the supply
voltage is restored before the enables for the 3SK1 safety relay can be switched through.
Startup testing ensures that any errors in the sensors are detected (again), because safety
relays lose their ability to store errors at zero voltage.
Unauthorized manipulation of the protection equipment can also be detected through startup
testing.
The plant operator decides whether startup testing should be performed (risk assessment).
No general statements apply.
Note
In the delivery state of 3SK1 safety relays, startup testing is deactivated.
4.3.13

Connection of actuators

Note
To achieve the Performance Level / Safety Integrity Level given in the following examples,
the actuators shown must be monitored in the feedback circuit of the corresponding safety
relay.
Note
For capacitive and inductive loads, we recommend an adequate protective circuit. In this
way, electromagnetic interference can be suppressed and contact service life increased.
You can find more information in the SIRIUS Innovations - SIRIUS 3RT2
Contactors/Contactor Assemblies manual
(http://support.automation.siemens.com/WW/view/en/60306557)
3SK1 safety relays
Manual, 04/2013, A5E02526190021A/RS-AA/01
Safety systems - General information
4.3 Basic terminology
37