How can I add timer function?

[skyhj105]

Hi. I have a question.

I made a labview program which can do PID contoll.

But I don`t know how can add timer function.

1.When temperature is higher than set point, Timer have to be started.

2.After time which I set in timer, PID have to be off

3.But temperature is measuring and all temperature which is measured at all process should be plotted in one graph at real time.

How can I add this function in my labview?

[skyhj105]

Solved

[GerdW]

Hi sky,

don't you think it would help other people when you would share the solution instead of writing just "solved"?

😉

[skyhj105]

I`m sorry. But I`m not solve it by not a labview but other instrument.

So, I think that It can`t be help other. As a result, I wrote like that.

If you mind, I`m so sorry.

[GerdW]

Hi sky,

you also could solve the problem in LabVIEW, maybe utilizing ElapsedTime function.

Please keep in mind the suggestions you already got in your other thread on sequence frames, misuse of BytesAtPort function, repeated opening and closing serial ports…

[skyhj105]

Ok. Thank you for ur advice.

[RTSLVU]

I just looked at your LabVIEW and have to say there is no wonder you had to use an external hardware soultion, your code has so many things wrong with it you should scrap the whole thing and start over.

Here's a couple points.

1. Don't open and close the VISA session every time you need to read or write to the serial port.
2. Open all VISA sessions ONCE at the beginning of your program and pass the VISA reference throughout your program
3. Close all VISA sessions ONCE at the end of your program, make that the last thing you do before exit.
4. Lose the Flat Sequence Structures, use a proper program architecture like a State Machine. 
5. Using a State Machine makes it trivial to add functions like timers, waits, and loop to different states depending on readings.