multiple PID blocks

[jpsimoes]

Hello,

I'm trying to use two PID blocks in a VI to implement two cascaded PI controllers.
When I set the gains in one of the blocks it also changes the gains of the other block. I can't use two PIDs even if I make two SAVE AS of the original block for the different PIs!
Is there any solution for this?

Thank you,
João

[altenbach]

You stumbled into the Forum feedback board by mistake.

What is a "PID block"? Depending on the answer, your post belongs into the LabVIEW board: http://forums.ni.com/ni/board?board.id=170 or one of the hardware boards.

[tst]

And while you're posting your question, it would be good if you post your code as well (File>>Save with Options>>Development Distribution). It would make it much easier.

As a shot at guessing the answer - the PID VIs supplied with the control toolkit are reentrant - they can be used multiple times in parallel to achieve different results. If you wrote a VI that wraps them, you should make it reentrant as well. Go to File>>VI Properties>>Execution and check Reentrant Execution. This will mean each time you place the VI on the diagram a new copy will be "created in memory", so they can have different data. Read the help on this for some more details.

[jpsimoes]

Hi!

I'm sorry for posting in the wrong forum.

Attached I send my VI. Even with the reentranted option checked the problems remains.

Thanks for the help!