As an execution unit, the electric actuator plays an important role in the electric unit combined instrument. It can coordinate with a variety of electric operators to promote the formation of disturbance-free switching mode, thereby realizing automatic adjustment. It has good application value in petrochemical, electric power and boiler system water supply.
There are three main control methods:
1. Analog control, input and output 4~20ma current.
2. Switching, divided into active and passive.
3. Protocol control method.
Main functions
1. Torque protection
It is used to prevent the actuator from over-torque during operation. This function protects both the valve and the actuator itself.
2. Limit protection
The actuator stops automatically when it runs to the closed and open limit positions.
3. Automatic phase sequence adjustment
The electric valve actuator automatically detects the phase sequence of the three-phase power supply connected to the power terminal, and determines which AC contactor to excite when the actuator is operated through appropriate logical operations. If there is no automatic phase sequence adjustment function, the valve may be damaged due to incorrect wiring phase sequence. Due to the automatic phase sequence adjustment function, the wiring of the actuator power supply can be done without considering the phase sequence.
4. Instantaneous reversal protection
When the actuator receives a command to move in the opposite direction, a time delay is automatically added to prevent unnecessary wear on the valve shaft and gearbox.
5. Power phase loss protection
The actuator adopts a method combining monitoring voltage and current to detect power phase loss when the motor is stationary and power phase loss during motor operation, thereby prohibiting the motor from running and avoiding motor overheating caused by phase loss operation.
