Siemens SIMATIC S5 Manual page 118

IP 265
Set/Reset operations (S/R..)
Set/Reset operation
Set/Reset operation for latching signal output
(reset dominant) "S":
The language element has one Set input (S), one
Reset input (R) and one output (Q). The Reset input
is dominant.
Example: If inputs I 0.0 and I 0.1 are both "1", the
operation is reset dominant. Output
Q 0.5 is "0".
Set/Reset operation for latching signal output
(set dominant) "R":
The language element has one Set input (S), one
Reset input (R) and one output (Q). The Set input is
dominant.
Example: If inputs I 0.0 and I 0.1 are both "1", the
operation is set dominant. Output Q 0.5
is "1".
Note
The Set/Reset operations are not assigned a flag number in the IP 265 user program.
Possible options for Set/Reset operations:
• Each input can be inverted.
• Outputs can be inverted when the output of the relevant language element leads immediately to
the output bar of the control system flowchart.
• Each of the two Set/Reset operations can be converted into its opposite operation or into a
binary logic operation.
EWA 4NEB 812 6130-02a
Table 9-3. "Set/Reset operations"
Programming the IP 265 with COM 265
CSF (example)
I 0.0
S
I 0.1
R Q
I 0.1
R
I 0.0
S Q
Q 0.5
Q 0.5
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