TOF off-delay timer symbol
Also called TOF, Off delay timer, Timer off delay
An off-delay timer: Q goes true as soon as IN is true, and stays true for the preset PT after IN goes false.
IEC 61131-3What the TOF off-delay timer symbol means
An off-delay timer: Q goes true as soon as IN is true, and stays true for the preset PT after IN goes false.
How it is drawn
IEC 61131-3 ladder diagram
TOF function block. A box marked TOF with inputs IN and PT and outputs Q and ET.
LD SVGWhere you see it
Keeping something running for a while after its command stops: a cooling fan, a lubrication pump, a light.
Related symbols
Frequently asked questions
What does the TOF off-delay timer symbol look like?
A box marked TOF with inputs IN and PT and outputs Q and ET.
Where is a TOF off-delay timer used?
Keeping something running for a while after its command stops: a cooling fan, a lubrication pump, a light.
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