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[ATR142-ABC] Dual Action Heating-Cooling with PID

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user497
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[ATR142-ABC] Dual Action Heating-Cooling with PID

Post by user497 »

Ciao!

Can You help us with one question:

We are using dual action heating-cooling mode with PID control with ATR142-ABC.
Problem: Heating is very slow process, it is going up till 210 ( Set point = 210C ) and already closing it and giving cooling output signal! Then it reach 211C and as it is already in cooling output, it goes down, after that the T is going down, and reaching 208, it begin to turn of cooling and start to open heating output again, after some while it is already fully open with heating output and process have to go up, but it is still falling down till 202-204C (reason is cooling output time that was open before). And just after some minutes it is going up till 210C.

Is there some possibility to change some parameters, that cooling does not open so fast, or maybe better, that it does not close the heating output for 100% ? (Maybe some overshoot possibilitys or cooling, that it can start cooling at 214? With the same setpoint?

Grazie!
Pixsys tecnico 1
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Re: Dual Action Heating-Cooling with PID.

Post by Pixsys tecnico 1 »

What type of cooling fluid do you use?
You have to set it in the "coof" parameter and then recalculate the PID parameters using the auto-tune function. Leave the "oudb" parameter to "0" to avoid overlapping between the two actions.
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