Application 3.1 (Sil3/Cat.4/Ple) - Siemens Simatic S7-1500 Manual

Applications of the F-I/O module
5.4 Application 3: Safety mode SIL3/Cat.4/PLe
5.4.1

Application 3.1 (SIL3/Cat.4/PLe)

Wiring diagram – connecting a two-channel sensor via two channels
A two-channel sensor is connected to two inputs of the F-module for each process signal
(1oo2 evaluation).
Supply the sensors from two different internal sensor supplies.
Alternatively, two single-channel sensors can be connected via two channels. In this case,
the same process variable is acquired with two mechanically separate sensors.
The figure below shows an example of the pin assignment of the fail-safe digital input
module F-DI 16x24VDC with two-channel connection of one two-channel sensor or two
single-channel sensors.
①
Backplane bus interface
②
Microcontroller 1
Image 5-5 One two-channel sensor connected via two channels (top) or two single-channel sensors connected via two
channels (bottom); internal sensor supply
To achieve SIL3/Cat.4/PLe using this wiring, you must use a suitably qualified sensor.
42
WARNING
③
Microcontroller 2
④
Reverse polarity protection
Digital input module F-DI 16x24VDC (6ES7526-1BH00-0AB0)
Manual, 01/2016, A5E03858068-AA