Signal conversion formula
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For a control valve, 4 mA corresponds to an opening degree of 0, and 20 mA corresponds to an opening degree of 100. So what value in mA does an opening degree of 80 correspond to? Please provide the conversion formula. Thank you. Shouldn’t this type of valve be called a direct-acting valve?
Whether the direct and reverse actions apply to the actuator or to the valve determines different starting points and thus different conclusions. When discussing the direct and reverse actions in a circuit, the valve is considered to have direct action; when discussing the actuator, it is considered to have reverse action. Assuming x represents the ma value: (x-4)/(20-4) = (80-0)/(100-0)
Parabola: quickly compute it; the results vary depending on different percentage values
It’s a very basic question; there are many of them on the website
It’s a very basic question; there’s plenty of information available on the website
The difference between direct-acting and reverse-acting valves is that when the signal increases, the valve stem moves downward in the case of a direct-acting valve; it moves upward in the case of a reverse-acting valve. (x-4)/(20-4)=80%
Very detailed: 4, 8, 12, 16, 20 mA; 0%, 25%, 50%, 75%, 100%; 0, 25, 50, 75, 100 units
Regardless of the action/reaction effect, the signal and opening degree correspond to 4–20 milliamps for values ranging from 0–100%, following a linear equation of the first degree
I agree. Parabolas, quick opening – the calculation methods for different percentages are all different; the calculation method used on the sixth floor above is linear!
16x0.8+4=16.8mA The valve is normally open!