Function Block - Off timer.
IN : BOOL
Timer command
PT : TIME Programmed time
RST : BOOL Reset (TOFR only)
Q : BOOL
Timer elapsed output
signal
ET :
TIME Elapsed
time
The timer starts on a falling pulse of IN input. It stops when the elapsed time is equal to the programmed time. A rising pulse of IN input resets the timer to 0. The output signal is set to TRUE on when the IN input rises to TRUE, reset to FALSE when programmed time is elapsed..
TOFR is same as TOF but has an extra input for resetting the timer
In LD language, the input rung is the IN command. The output rung is Q the output signal.
(* MyTimer is a declared instance of TOF
function block *)
MyTimer (IN, PT);
Q := MyTimer.Q;
ET := MyTimer.ET;
(* MyTimer is a declared instance of TOF
function block *)
Op1: CAL MyTimer (IN, PT)
LD MyTimer.Q
ST Q
LD MyTimer.ET
ST ET