Siemens SINAMICS S120 Manual page 59

Emergency Stop
If, while the motor is rotating, switch -S1 is actuated, then safety function STO is
activated. After selecting STO, the converter safely switches off the torque of the
connected motor.
Protective door
Switch -S2 simulates a protective door. As long as switch -S2 is not actuated (high-
level), the protective door is closed. In this particular case, the drive can be
operated at any speed (precondition, -S3 is not actuated. If switch -S2 is actuated
(low signal), then this corresponds to the protective door being opened. Safety
function SLS with SLS level 1 is selected. After a configurable time has elapsed,
the speed is safely monitored against a limit value (in this case, 750 rpm). For an
active SLS level, the corresponding stop response STOP C is initiated when this
limit value is exceeded. This means that the drive is braked along the OFF3 ramp,
and after a configurable delay time has elapsed, standstill (zero speed) is
monitored using the SOS safety function. In this particular case, the drive remains
in the closed-loop controlled mode. Safety messages C01714 and C30714 are
output.
Light barrier
Switch -S3 simulates a light barrier. As long as switch -S3 is not actuated (high-
level), the light barrier is not interrupted. In this particular case, the drive can be
operated at any speed (precondition, -S2 is not actuated. If switch -S3 is actuated
(low signal), then this corresponds to the light barrier being interrupted. Safety
function SLS with SLS level 1 is selected. However, here the limit value of SLS
level 1 is reduced by the F-CPU to 40%. After a configurable time has elapsed, the
speed is safely monitored against a limit value (in this case, 300 rpm). For an
active SLS level, the corresponding stop response STOP C is initiated when this
limit value is exceeded. This means that the drive is braked along the OFF3 ramp,
and after a configurable delay time has elapsed, standstill (zero speed) is
monitored using the SOS safety function. In this particular case, the drive remains
in the closed-loop controlled mode. Safety messages C01714 and C30714 are
output. Switch -S3 always has priority over -S2, i.e. when switches -S2 and
-S3 are simultaneously actuated, the SLS speed is limited to 300 rpm.
Reintegrating/acknowledging safety faults
The drives have to be reintegrated after power OFF/ON. All of the safety fault
messages are acknowledged by pressing -S4, and signal lamp -S4 is turned on.
The signal lamp goes dark if the specified SSM limit is exceeded.
Test stop
A test stop can be carried out using button -S8.
PROFIsafe SLS Override
Version 1.0, Entry ID: 81682475
7 Operating the application
59