CTU up counter symbol
Also called CTU, Count up counter
An up counter: each rising edge on CU adds one to the count CV, and Q goes true when CV reaches the preset PV. R resets the count.
IEC 61131-3What the CTU up counter symbol means
An up counter: each rising edge on CU adds one to the count CV, and Q goes true when CV reaches the preset PV. R resets the count.
How it is drawn
IEC 61131-3 ladder diagram
CTU function block. A box marked CTU with inputs CU, R and PV and outputs Q and CV.
LD SVGWhere you see it
Counting parts, cycles or events, and acting after a set number.
Related symbols
Frequently asked questions
What does the CTU up counter symbol look like?
A box marked CTU with inputs CU, R and PV and outputs Q and CV.
Where is a CTU up counter used?
Counting parts, cycles or events, and acting after a set number.
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