F_TRIG falling edge symbol
Also called F_TRIG, Falling edge detector, OSF
A falling edge detector: Q is true for one scan when CLK changes from 1 to 0.
IEC 61131-3What the F_TRIG falling edge symbol means
A falling edge detector: Q is true for one scan when CLK changes from 1 to 0.
How it is drawn
IEC 61131-3 ladder diagram
F_TRIG function block. A box marked F_TRIG with input CLK and output Q.
LD SVGWhere you see it
Acting once when a signal drops: a motor stopped, a part has left a sensor.
Related symbols
Frequently asked questions
What does the F_TRIG falling edge symbol look like?
A box marked F_TRIG with input CLK and output Q.
Where is a F_TRIG falling edge used?
Acting once when a signal drops: a motor stopped, a part has left a sensor.
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