Siemens SIMATIC ET 200SP Equipment Manual page 41

Figure 5-3 A two-channel sensor connected via two channels, internal and external sensor supply
To achieve SIL3/Cat.3/PLe using this wiring, you must use a suitably qualified sensor.
Wiring diagram - connecting two one-channel sensors equivalent via two channels
Per process signal, two one-channel sensors, which record the same process value, are
connected equivalent via two channels to two inputs of the F-module (1oo2 evaluation).
Any sensor supply of the module can be assigned to each input.
You can also supply the sensors by means of an external sensor supply.
Digital input module F-DI 8x24VDC HF (6ES7136-6BA01-0CA0)
Equipment Manual, 10/2021, A5E50578307-AA
WARNING
Applications of the F-I/O module
5.3 Application 2: Safety mode SIL3/Cat.3/PLe
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