Siemens SIMATIC S7 F Manual page 143

Programming
What to Remember When You Simulate Safety Programs
Safety Note – Simulation Warning
!
This is not a substitute for a function test!
If the simulation takes place on a programming device or ES with a physical online
connection to the CPU, you must not deactivate safety mode and you must not
have access rights by means of the CPU password.
The driver blocks do not access the I/O.
Input signals of F input modules can be modified in the process input image (PII) of
PLCSim.
Communication between CPUs cannot be simulated.
Fail-Safe Systems
A5E00085588-03
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