Siemens SIMATIC S7 Functional Safety Manual page 159

Note
Unused analog inputs should be shorted.
S7-1200 Functional Safety Manual
Manual, 02/2015, A5E03470344-AA
Pin X10
17 DI b.2
18 DI b.3
19 DI b.4
20 DI b.5
Technical specifications
A.2 Fail-Safe CPU technical specifications
X11 (gold)
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X12
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