Siemens SIMATIC STEP 7 V5.2 Getting Started page 26

Creating a Program in OB1
4.2 Programming OB1 in Ladder Logic
In the following section, you will program a series circuit, a parallel circuit, and the
set / reset memory function in Ladder Logic (LAD).
Programming a Series Circuit in Ladder Logic
4-4
If necessary, set LAD as the
programming language in the View
menu.
Click in the title area of OB1 and enter
"Cyclically processed main program,"
for example.
Select the current path for your first
element.
Click the button in the toolbar and
insert a normally open contact.
In the same way, insert a second
normally open contact.
Insert a coil at the right-hand end of
the current path.
The addresses of the normally open
contacts and the coil are still missing in
the series circuit.
Check whether symbolic
representation is activated.
STEP 7 Getting Started
A5E00171228-01