Safety Mode - Siemens SIMATIC S7 F Manual

Safety Mechanisms
3.2

Safety Mode

The safety-related functions for fault detection and fault reaction are activated in
safety mode.
•
In the F-I/Os
•
In the Safety Program of the CPU
Safety Mode of the F-I/Os
When configuring the F-I/Os in HWCONFIG, you can use the "Safety Mode"
parameter to set standard mode or safety mode for them, if this feature is
supported:
•
To set standard mode, do not select the "Safety Mode" parameter.
•
To set safety mode, select the "Safety Mode" parameter.
You can find additional information on standard mode and safety mode in manual
/1/. (Please refer to the references in Appendix B.) You can find information on the
parameter assignment of the F-I/Os in the online help system and in the section
"Configuring, Parameter Assignment of F-I/Os".
Safety Mode of the Safety Program
The Safety Program usually runs on the CPU in safety mode. In other words, all
the safety mechanisms for fault detection and fault reaction are activated. It is not
possible to change the Safety Program during operation when it is in safety mode.
Safety mode of the Safety Program in the CPU can be switched off and on again to
allow changes to the Safety Program during RUN mode. You can switch safety
mode on and off for the Safety Program in the CPU in SIMATIC Manager by
choosing the Options > Edit Safety Program menu command. You can find
further information on changing the Safety Program in RUN mode in the chapters
entitled "Programming, Deactivating Safety Mode" and "Changing the Safety
Program in RUN Mode".
3-2
Fail-Safe Systems
A5E00085588-03