Siemens SIMATIC STEP 7 V5.2 Getting Started page 35

Programming an OR Function in Function Block Diagram
STEP 7 Getting Started
A5E00171228-01
Creating a Program in OB1
Insert a new network.
Select the input area again for the OR
function.
Insert an OR box (≥1) and an
assignment (=).
The addresses are still missing in the
OR function. Proceed in the same way
as for the AND function.
Enter "Key_3" for the upper input,
"Key_4" for the lower input, and
"Red_Light" for the assignment.
Save the block.
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