Siemens S7-300 Installation And Operating Manual page 15

Optional applications for fail-safe signal modules
S7-300 fail-safe signal modules support applications for:
● S7-300 automation systems (centrally in S7-300; distributed in ET 200M)
● S7-400 automation systems (distributed in ET 200M)
Note
To use the HART function of the SM 336, F-AI 6 x 0/4 ... 20 mA HART analog module
requires distributed implementation in ET 200M.
F-System with fail-safe signal modules
The figure below shows an example configuration of an
fail-safe signal modules/modules in S7-300, ET 200M, and ET 200S.
Figure 1-1
Operation in standard mode
Except for the SM 326; DO 8 x DC 24V/2A PM, the SM 326; F-DO 10 x DC 24V/2A PP and
the SM 336; F-AI 6 x 0/4 ... 20 mA HART, you can operate all other fail-safe signal modules
in standard mode with more stringent diagnostics requirements. When operated in standard
mode, the fail-safe signal modules respond similar to standard S7-300 I/O modules.
Operation in safety mode
You can implement the fail-safe signal modules for operation in safety mode. Configure
safety mode in
panel of the fail-safe signal module. The "SAFE" LED is lit when safety mode is active at the
signal module.
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
Fail-safe S7 Distributed Safety automation system
HW Config STEP 7
of
1.2 Using Fail-Safe Signal Modules
S7 Distributed Safety
and using the address selector switch on the rear
Product overview
F-system with
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