During Simulation Of Input Channels The Simulation Value Is Always Available On The Block's Output - Siemens SIMATIC S7 F Manual

Programming
Safety Note – During simulation of Input Channels the Simulation value is
!
always available on the block's output.
In the event of an error with digital or analog input channels, if SIM ON=TRUE then
simulation values are placed on the block's output instead of the substitute values.
Error Handling and Diagnostics
You can find information on the diagnostic outputs of the F driver blocks under:
•
Error Handling of Driver Blocks
•
Error Information at the Outputs of the Driver Blocks
5-22
Fail-Safe Systems
A5E00085588-03