Omron NX-SL series

3 - 13
3 Safety Standard Function Blocks
NX-series Safety Control Unit Instructions Reference Manual (Z931)
3
SF_SR
SF_SR
This FB retains the value of a SAFEBOOL variable.
It gives priority to the Set input if both the Set input and Reset input are TRUE.
• This instruction forms a self-holding output that gives priority to setting. The following table shows the
relationship between the inputs and outputs.
The following figure shows a programming example and timing chart.
Instruction Name FB/FUN Graphic expression
SF_SR Set-Priority Keep FB
Variables
Input Variables
Variable Name Data type Valid range Default Description
SET1 Set SAFEBOOL TRUE or FALSE FALSE Set input (Given priority.)
RESET Reset BOOL TRUE or FALSE FALSE Reset input
Output Variables
Variable Name Data type Valid range Default Description
Q1 Keep SAFEBOOL TRUE or FALSE FALSE Keep output
Function
Value of SET1 Value of RESET Value of Q1
TRUE TRUE TRUE
TRUE FALSE TRUE
FALSE TRUE FALSE
FALSE FALSE Not changed.
SF_SR
SET1
RESET
Q1
Set1=A
Reset=B
Q1=abc
TRUE
FALSE
TRUE
FALSE
TRUE
FALSE