Siemens SIMATIC 6DL1 136-6AA00-0PH1 - Requirements Placed on Sensors for Fail-Safe Modules

6.9 Requirements placed on sensors for fail-safe modules
De󹪝nition
There are certain requirements for the safety-related use of sensors, which are brie󹪞y described
below.
General sensor requirements
For safety-related use of sensors, you must observe the following important warning:
WARNING
Sensor requirements
Note that a signi󹪝cant responsibility for safety of instrumentation lies with the sensors. Also
keep in mind that sensors generally do not have proof-test intervals of 20 years according to
IEC 61508:2010 without a signi󹪝cant loss of safety.
The probability of dangerous faults or the rate of dangerous faults of a safety function must
adhere to an SIL-dependent upper limit.
You will 󹪝nd the values achieved by the F-modules in their technical speci󹪝cations.
To achieve the respective safety class, correspondingly quali󹪝ed sensors are required.
(FAIW-010)
Additional sensor requirements
WARNING
Safe reaction of the safety program in case of sensor error
With the fail-safe analog input modules, the a󹪜ected input is passivated and the substitute
value is forwarded to the F-CPU after errors have been detected. You therefore need to take care
that the safe reaction of the safety program is achieved with the substitute value.
(FAIW-011)
Applications of the F-I/O module
6.9 Requirements placed on sensors for fail-safe modules
F-AI 8xI 2-/4-wire HART HA
Equipment Manual, 09/2021, A5E50557845-AA 57