What is the working principle of the electro-hydraulic linked ball valve? 8.1 Local Control Turn the black selector switch on the local controller to the ‘Local’ position. Local control can also be operated using a remote controller. 2.1.1 Opening the Valve Turn the black three-position rotary switch on the controller to the ‘Local’ position, then turn the red switch to the ‘Open’ position. The motor runs and drives the oil pump to generate high-pressure oil. The high-pressure oil enters the rodless chamber of the cylinder, and the solenoid valve YV is powered at the same time, driving the gear transmission mechanism to rotate counterclockwise. The actuator opens at a preset speed until it automatically stops at the fully open position. Note: If the rotary switch stays in the open position for more than 3 seconds, the ‘Open Valve’ knob automatically locks. At this point, even if you release the ‘Open Valve’ knob, the valve continues to open to the fully open position and the motor stops automatically. To stop in the middle, turn the red three-position rotary switch to the ‘Stop’ position. 2.1.2 Closing the Valve Turn the black three-position rotary switch on the controller to the ‘Local’ position, then turn the red switch to the ‘Close’ position. The motor runs and drives the oil pump to generate high-pressure oil. The high-pressure oil enters the cylinder rod chamber, driving the gear transmission mechanism clockwise. The actuator closes the valve at a preset speed until it automatically stops at the fully closed position. Note: If the rotary switch stays in the closed position for more than 3 seconds, the ‘Close Valve’ knob automatically locks. At this point, even if you release the ‘Close Valve’ knob, the valve continues to close to the fully closed position and the motor stops automatically. To stop in the middle, turn the red three-position rotary switch to the ‘Stop’ position. 2.1.3 Stop During opening or closing, turn the black knob to the ‘Stop’ position. Both the oil pump and solenoid valve lose power, and the valve stops at any intermediate position.