The set temperature for heating water with steam on-site is 30°C; after adjusting the steam control valve to 100% opening, it is set to 30°C
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The set temperature for heating water with steam on-site is 30°C; the steam control valve was opened to 100% to reach this temperature and then immediately closed completely. Shouldn’t the control valve be opened and closed gradually? It seems there is no regulation at all; presumably, when the set temperature is approached, the steam control valve gradually closes to allow the temperature to rise slowly. Once the set temperature is reached, the temperature should remain within a certain range, and the steam control valve should also adjust within that range, rather than opening or closing suddenly. Could it be that the control valve isn’t properly set?
The electric control valve used only has two control modes: on and off.
Is it possible that the pneumatic control valve uses PID control, but actually only PI control is employed, with the derivative term missing?
Is it possible that the pneumatic control valve uses PID control, but actually only PI control is employed, with the derivative term missing?
Does the valve have a positioner? Is it possible to set valve positions other than 0 and 100? It’s not possible to operate in automatic mode; switch to manual control. Determine which valve position is more stable, and then adjust the differential calculation algorithm to use automatic mode and reduce fluctuations
A soda mixer can be used directly; the temperature can be adjusted easily, and internally, a thermosensitive element is generally used to control the flow of steam.
Suggested adjustments for temperature control PID settings: P: 20-60, I: 180-600, D: 30-180
Should one first determine which valve opening level is more stable, and then adjust the differential setting? The minimum valve position should be set above 0 and below 100, trying to get as close as possible to the identified stable opening level in order to reduce fluctuations?