Siemens SIMATIC STEP 7 V5.2 Getting Started page 47

Programming an Engine to Switch On and Off
STEP 7 Getting Started
A5E00171228-01
Creating a Program with Function Blocks and Data Blocks
Local block variables are indicated with a # sign
and are only valid in the block.
Global variables appear in quotation marks.
These are defined in the symbol table and are
valid for the entire program.
Insert an SR function in Network 1
using the Program Elements catalog
(Bit Logic folder).
Add an AND box at input S (Set), and
an OR box at input R (Reset).
Check whether symbolic
representation is activated.
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