Siemens SIMATIC ET 200SP Equipment Manual page 49

Wiring diagram - connecting two one-channel sensors non-equivalent via two channels
Per process signal, two one-channel sensors, which record the same process value, are
connected non-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.
Figure 5-8
To achieve SIL3/Cat.4/PLe using this wiring, you must use a qualified sensor.
Digital input module F-DI 8x24VDC HF (6ES7136-6BA01-0CA0)
Equipment Manual, 10/2021, A5E50578307-AA
Two one-channel sensors connected via two channels non-equivalent, internal sensor
supply and two one-channel sensors connected via two channels non-equivalent,
external sensor supply.
WARNING
Applications of the F-I/O module
5.4 Application 3: Safety mode SIL3/Cat.4/PLe
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