paddy-dee Posted April 17, 2019 Report Share Posted April 17, 2019 Hello forumHave there a question about the PID controller. I use two PID controllers (auto tune) in master slave mode (cascade) to heat and cool. I switch with the BIT "action; 0 = Reverse (Heating), 1 = Direct (Cooling)" to heat or cool.My problem is the controller output:The controller is cool, the setpoint is not quite reached yet and the contoller output has eg a value of 20%. Now the actual value falls below the setpoint. So I switch the PID controller to "heat up". Now the controller output still has 20% at the output. When switching from cooling to heating, the controller output is not reset, also not recalculated for heating.Is there a way to reset the controller? So that he recalculates the controller output?I'm doing an ugly detour right now! I change the proportional band to 0.1% for one second and then back to the effective value. The controller output is calculated "new" again.Works, but I do not like it that way. Quote Link to comment Share on other sites More sharing options...
Gabriel Franco Posted April 17, 2019 Report Share Posted April 17, 2019 After you switch cooling/heating bit, you need to re-configure PID. Quote Link to comment Share on other sites More sharing options...
paddy-dee Posted April 18, 2019 Author Report Share Posted April 18, 2019 Dear Gabriel Thank you so much for this quick and perfect reply !!! Kind regards Patrick Quote Link to comment Share on other sites More sharing options...
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