The brake’s safety values must guarantee that the safety level of the overall safety
function is PL e.
6.4.5
Safe SLS request signal
The safe signal source and the transmission path must comply with category 4, PL e. If
an external signal is not used, the function must be deactivated in the logic.
The dual-channel inputs for the
SLS Request
signal must always be set to High (24 V DC)
if there is no request for the speed to be limited or if an external signal is not used. If
safely limited speed has been requested, both inputs must be switched to Low (0 V).
Both channels for the safe SLS Request signal must change their status at the same
time, whereby the maximum permitted difference in time is 1 s.
6.4.6
Signal for emergency stop pushbutton
The Flexi Soft safety controller provides a dual-channel input signal for an SF200 emer‐
gency stop pushbutton.
Depending on the transport system being used within the application, a pushbutton
can be mounted directly on the vehicle and near to the rails. The signal path must
always correspond to category 4.
NOTE
The operating entity must press the emergency stop pushbutton at least every
six months to test that it is working properly. The device used for shutting down in an
emergency must meet the requirements of IEC 60947-5-5.
6.4.7
Signal for restart interlock
Manual reset
When a protective device requests a stop command, the stop status must apply until a
manual reset has been performed. A separate reset device (e.g., a pushbutton) must
be relied upon to perform this manual reset and must be in a position that allows for
the results of a restart to be overseen.
It must be possible for a falling signal edge, triggered by the reset device, to be
detected during processing. It should only be possible to reset when all safety functions
and protective devices are fully functional and active.
The reset device signal forms part of the safety functions. This means that it must have
one of the following properties:
•
Discrete wiring with the safety logic
•
Transmission via a safety bus system
Restarting must not bring about any movements or hazardous situations. The applica‐
tion is only permitted to accept a separate start command after a reset.
Starting and restarting
An automated restart must only be performed if there is no risk of a hazardous situa‐
tion.
ELECTRICAL INSTALLATION
6
8020941/12O9/2019-08-05 | SICK
O P E R A T I N G I N S T R U C T I O N S | Safe Linear Positioning
31
Subject to change without notice
