Output limit on PID function block

[Anonimo]

Hello to all, I test the PID Manager function block and it’s work fine. I am having problem with limiting PID output to in range 0-100.

If error is negative the PID output value must stop to 0, when the error becomes positive it must start form 0 to 100. Could I do that in some way ?

[Sergio Bertana]

The PID output is limited to ±100% inside the FB. Normally in the PID regulations it’s necessary to have a regulation that’s work bidirectionally to correct the error when it’s negative or near to “0”.

If your requirements are to manage a one quadrant regulation, you can discard the output values less than 0. Obviously the internal I and D errors increasing if the error remains negative for a time, so it’s necessary to disable the PID regulation (Or only the I and D corrections) after a time that the error remains negative.

[Anonimo]

Hello, thank you for answer and help. My first idea was to limit PID output and somehow disable increasing negative value, now you give me a clear answer.

I hoped that there was limits inside the FB but this is also fine.

[Autore]

Post