The DKJ-4100 D and DKJ series electric actuators are position servo mechanisms driven by a two-phase AC servo motor. When a signal is input to the position controller, it is compared with the position signal. When the deviation exceeds the specified dead zone, the controller generates a power output and drives the servo motor to rotate, causing the output shaft of the reducer to turn in a direction that reduces the deviation until the deviation is smaller than the dead zone. At this point, the output shaft stabilizes at the angle corresponding to the input signal. Since the motor is equipped with a braking structure, it can reliably ensure rapid braking after power-off, thereby limiting the output shaft's inertia and overcoming the effects of load reactive torque, effectively improving system stability. Through the DFD electric manipulator, the actuator can switch between manual control, automatic control, and manual remote operation without interference. By connecting a DC milliammeter in the system's position feedback loop, the output current of the position transmitter can be measured, which indirectly indicates the valve opening.