I have a setup of 3 200 liter unitanks and a chiller. Everything runs smooth but after haveing just started my 2nd batch there seems to be a need for some adjustment of the PID settings.
This batch was a little too warm when I transferred to the unitank (23,5 vs a Target of 20)
The cooling has now resulted in a ~5 degree undershoot of the temp. What puzzles me is that the controller seemed to continue to add periods of cooling even after the temperature was below target (see first screenshot). I only have cooling added to the tank, no heating.
I’ve also inserted a screenshot of the PID graph for the couple of hours around the time where it drops below target.
Can you please advice what I should adjust?
As a side note, the system is brilliant at keeping a stable temperature or reducing the temperature slowly using a temperature profile