Siemens 020-011 Manual De Usuario
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
OR logic operation in FBD:
In FBD, the OR operation is programmed trough graphic representation and looks like this:
5.7.3 Negation
In logic operations it is often necessary to poll whether a NO contact was NOT operated or whether a
NC contact was operated, and there is no voltage at the corresponding input for that reason. .
This is done by programming a Negation at the input of the AND or OR logic operation.
In FBD, the negation of an input is programmed at an AND logic operation with the following graphic
representation:
Voltage is applied to output %O 0.0 exactly when %I 0.0 is not wired
and %I 0.1 is wired.
=
%O 0.0
%I 0.1
%I 0.0
Inputs of the OR
logic operation.
There can be more
than 2 inputs here!
logic operation.
There can be more
than 2 inputs here!
Output to which
the assignment is
allocated!
the assignment is
allocated!
Graphic representation
of the OR logic
operation!
of the OR logic
operation!
Assignment of the
result of the logic
operation!
result of the logic
operation!
>
&
=
%O 0.0
%I 0.1
%I 0.0
Input of the AND
logic operation that is
to be negated!
logic operation that is
to be negated!
Graphic representation
of the negation!
of the negation!