Connecting Global Data - Siemens SIMATIC S7-1200 Safety Programming Manualline

3 Methods for Safety Programming
3.8 Accessing global data
Recommendation

Connect global data (inputs, outputs, data blocks) at the highest block
hierarchy level (Main Safety).

Use the block interfaces to pass signals to lower levels.
Advantages

Modular block concept

Reuse of program parts in other projects without modifications

Reduces programming errors

Makes the overall program easier readable as the general function of a block
can already be estimated from the interfaces.
Figure 3-9: Connecting global data
Safety Programming Guideline
Entry ID: 109750255, V1.0, 10/2017
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