Siemens SIMATIC ET 200S Installation And Operating Manual page 120

Fail-Safe Modules
7.5 4/8 F-DI VDC24V PROFIsafe Digital Electronic Module
Figure 7-23
Warning
To achieve AK6/SIL3/Category 3 using this wiring, you must use a sensor qualified for this
class.
Assignable Parameters for Use Case 2.1
Set the parameter "evaluation of sensors" to "1oo2 evaluation" for the corresponding sensor
and the parameter "type of sensor interconnection" to "1-channel" . The discrepancy time is
permanently preset to 10 ms and cannot be changed.
You can activate or deactivate the "short-circuit test" parameter. However, you must
deactivate the short-circuit test as soon as one or more fail-safe digital inputs are externally
supplied. Otherwise the "short circuit" diagnosis may be reported.
7-60
Wiring Diagram EM 4/8 F-DI DC24V - One Channel of a Sensor Connected to Two
Inputs, External Power Supply
Hardware Installation and Operating Manual, 07/2005, A5E00103686-04
ET 200S Distributed I/O System - Fail-Safe Modules