Hi,

using Codesys 2.3
I can't get how to reuse a pulse timer.
Attached is a simple project with one SFC program, which tries to use a TP timer declared as TP1 global.

It works only once after a PLC reset.

If I set TP1.IN from an action(TransA -> Step1A), the first time it works.
TP is started, .ET increases etc.
The next time I set .IN, nothing happens as .ET is already equal to .PT
I can't reset .ET to 0, it doesn't reset automatically, so how am I supposed to reuse the timer?

If I set TP1.IN from an ENTRY action(TransB -> Step1B), TP1.Q becomes true forever and TP1.ET stays at 0.

It should be obvious already that I'm a complete newbie.
How all this works and how to reuse a timer?

Thanks.

tp2.pro [28.9 KiB]

please ignore, I've found what's wrong.
Instead of TP1.IN:=FALSE; I should have used TP1(IN :=FALSE);
Not so obvious at first sight

Sorry I hope you don't mind if I explain the difference between the two calls for people who might be wondering.

TP1.IN:=FALSE; this sets the variable but never jumps to the instance of the timer TP1 in memory to reload the algorithm.

TP1(IN:=FALSE); this sets the variable and jumps to the instance of the timer TP1 in memory and calls/runs the algorithm.

EXAMPLE:

PROGRAM PLC_PRG
var
 Timer :TON;
end_var
Timer(IN := TRUE, PT:= T#5s);
Timer.PT := T#10s;
end_Program

The outcome of the timer will be Timer.Q := TRUE after 5 sec not 10 sec.