Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
13
Product overview
1
1.1
Introduction
In this chapter
The product overview provides information about
●
the integration of fail-safe signal modules in SIMATIC S7 fail-safe automation systems
●
available fail-safe signal modules
●
steps to take, starting with the selection and ending with the commissioning of fail-safe
modules.
1.2
Using Fail-Safe Signal Modules
Fail-safe automation system
Fail-safe automation systems (F-systems) are used in plants which are subject to more
stringent safety standards. F-systems are used to control processes and to force the plant
into a safe state after shutdown. That is, F-systems control processes which do not pose a
risk to human beings or to the environment when shut down immediately.
Fail-safe signal modules
Compared to standard modules of the S7-300 module family, the fail-safe signal modules
differ in terms of their internal dual-channel structure. The two integrated processors monitor
each other, automatically test the I/O circuits, and force the fail-safe signal module into safe
state when a fault/error has been detected. The F-CPU communicates with the fail-safe
signal module by means of the safety-oriented PROFIsafe bus profile.