Siemens Sinamics G120 CU240E Operating Instructions Manual page 198

Functions
5.12 Safety-related applications
Controlling the safety functions
The safety functions in the frequency inverter can be controlled via fail-safe digital inputs as
well as over safe bus communication PROFIsafe via PROFIBUS or PROFINET in
conjunction with a fail-safe CPU.
Safe feedback from the frequency converter
When fail-safe functions are used, feedback is generally required as to whether or not the
drive is in a safe state.
With the SLS function, for example, this is the case if the frequency inverter has decelerated
the motor to below the speed monitoring limit. This safe state is signaled by the frequency
inverter via fail-safe channels. On the basis of this, a higher-level controller can trigger
further actions (e.g. enable a protective door).
Fail-safe feedback signals from the frequency inverter are realized using PROFIsafe.
198
Frequency inverter
Operating Instructions, 08.10. 2008, t.b.d.