SR set-dominant bistable symbol
Also called SR, Set dominant latch, Flip-flop
A latch where set wins: Q1 goes true on S1 and false on R, and if both are true, Q1 stays true.
IEC 61131-3What the SR set-dominant bistable symbol means
A latch where set wins: Q1 goes true on S1 and false on R, and if both are true, Q1 stays true.
How it is drawn
IEC 61131-3 ladder diagram
SR function block. A box marked SR with inputs S1 and R and output Q1.
LD SVGWhere you see it
Latches where the set must win, such as holding a run request.
Related symbols
Frequently asked questions
What does the SR set-dominant bistable symbol look like?
A box marked SR with inputs S1 and R and output Q1.
Where is a SR set-dominant bistable used?
Latches where the set must win, such as holding a run request.
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