Siemens 020-011 User Manual
Industry Sector, IA&DT
SCE Training Curriculum
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TIA Portal Module 020-011, Edition 04/2014
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SCE_EN _020-011_R1404_Startup Programming with SIMATIC S7-1500
5.7.2 OR Logic Operation
Example of an OR logic operation:
A lamp is to be lit when one or both of two switches is operated as NO contact.
Circuit diagram:
Explanation:
The lamp is lit exactly when one or both switches are operated; i.e., if switch S1 or S2 is operated, lamp
P1 is on.
PLC wiring:
To implement this logic in a PLC program, both switches have to be connected to the inputs of the PLC,
of course. Here, S1 is wired to input %I 0.0 and S2 to input %I 0.1.
In addition, lamp P1 has to be connected to an output; for example, %O 0.0.
of course. Here, S1 is wired to input %I 0.0 and S2 to input %I 0.1.
In addition, lamp P1 has to be connected to an output; for example, %O 0.0.
M
24V
M
S1
S2
P1
24V
PLC
Inputs
Switch S1
Switch S2
%I 0.0
%O 0.0
Outputs
Lamp P1 is to be lit
when switch S1 or
S2 is operated.
when switch S1 or
S2 is operated.
24V
%I 0.1
24V