Siemens SIRIUS 3RK3 - Operation; Response Times; Notes and Definitions

Operation
6
6.1 Response times
6.1.1 Notes and de󹪝nitions
Reaction time (in error-free operation)
The reaction time is the time until a system responds at the output after a change of an input
variable, i.e. the time between the event and the action, e.g. terminal to terminal or sensor to
actuator for operational switching.
The reaction time in error-free operation is calculated to de󹪝ne the process in the system. This
time is not suitable for the determination of safety clearances in the system.
Fault reaction time (reaction time in the event of a fault)
The fault reaction time is the time between detecting a hazardous fault in a system and that
system entering the safe state.
The fault reaction time of the MSS 3RK3 depends on whether a safety-related output is
controlled through one channel or two.
Veri󹪝cation of reaction times in the case of safety circuits
When safety equipment is commissioned, steps must be taken to verify that it will shut down
within a maximum permissible time after the safety function has been requested.
To provide this veri󹪝cation, you must determine the reaction times of the application you have
con󹪝gured.
WARNING
Hazardous system state
Can Cause Death, Serious Injury, or Property Damage.
Note that the calculation of the reaction times a󹪜ects the level of safety and in󹪞uences the
overall design of the system.
Note
Field bus signals
If 󹪝eld bus signals are logically combined, runtime synchronism must be considered. It is the
responsibility of the manufacturer to ensure that the system or machine is functioning properly
as a whole.
SIRIUS 3RK3 Modular Safety System
Equipment Manual, 07/2020, NEB926253002000/RS-AC/006 171