Siemens SIMATIC S7-1200 - Page 305

Basic instructions
8.8 Program control operations
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
305
Adding inputs, deleting inputs, and specifying comparison types
When the LAD or FBD SWITCH box is first placed in your program there are two comparison
inputs. You can assign comparison types and add inputs/jump destinations, as shown below.
Click a
comparison operator inside the box and select a new operator
from the drop
-down list.
Click the create icon inside the box (to the left of the last DEST p
a-
rameter) to add new comparison
-destination parameters.
•
Right-click on an input stub and select the "Insert input" command.
•
Right-click on an input stub and select the "Delete" command.
Table 8- 135 SWITCH box data type selection and allowed comparison operations
Data type
Comparison
Operator syntax
Byte, Word, DWord
Equal
==
Not equal
<>
SInt, Int, DInt, USInt, UInt,
UDInt, Real, LReal, Time, TOD,
Date
Equal
==
Not equal
<>
Greater than or equal
>=
Less than or equal <=
Greater than
>
Less than
<
SWITCH box placement rules
● No LAD/FBD instruction connection in front of the compare input is allowed.
● There is no ENO output, so only one SWITCH instruction is allowed in a network and the
SWITCH instruction must be the last operation in a network.