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timerplcst

How do you let define the delay time for a timer in ST?

I'm trying to write a program in ST to let the user define the Bakelength time (in hours) for a TON timer.

I have this currently but when I compile the code, the program throws up an 'illegal constant' error. How would I change this syntax? Any help would be much appreciated!!!

TON_1(IN:= true,PT:= t#(BakeLength)h);
Solution

  • The annotation with T# is just to define constant values in your source code like T#100s.

    If Bakelength is already a variable of type TIME you can just write

    TON_1(IN:= true,PT:= BakeLength);

    If Bakelength is another type e.g. LREAL you have to convert the value to a TIME variable. Numeric DataTypes are always interpreted as milliseconds if you convert to TIME. Therefore if Bakelength is in hours you have to multiplicate with 3600000.

    TON_1(IN:= true,PT:= LREAL_TO_TIME(Bakelength * 3600000));