There are two types of electric butterfly valves: common type and intelligent type. Ordinary type, when the motor is connected, the valve will open or close, depending on the positive and negative rotation of the motor; For intelligent type such as AC380V, after AC380V is supplied to it, the motor does not move and the internal control circuit board can work. When 4-20mA current is input to it, corresponding actions shall be taken. Close at 4mA and open at 20mA. And there is 4-20mA analog quantity feedback signal to reflect its valve opening.
