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CM50 Boundless Control - Rapid relay switching

Dear Experts,

Good day!

Recently I have posted a query regarding CM50 controllers.

Now, as I tune each one them, one CM50 is giving me some headache.

I am implementing a boundless control for a loop. Other loops I have tuned are doing fine exept this one. The relays for open and close command are rapidly switching.

I have configured sets of PID parameters even copying known working ones from other loops just to know what is wrong. Only when I increase values in the travel time, the rapid switching decreases but the controller action is to OPEN only the valve even if it is very far from the setpoint and needs to close already.

Also, the deadband is very puzzling to me because when I input none (0), the controller does not respond at all.

Can somebody here give me some useful tips or advise on how to implement this boundless control?

Thank you very much. Hoping for your responses.

ry_fern