What are the control methods for electric actuators?
The valve controller is actually called the positioner, which is the brain of the valve. The position signal is collected by the feedback lever, the signal is processed, and the corresponding signal is output to the actuator.
The electric actuator in the actuator is the hand of the valve, receives the air pressure from the locator, then produces the displacement, through the displacement to control the opening of the valve.
Valve type is quite a lot, the working principle is not quite the same, generally to rotate the valve plate angle, lifting valve plate and other ways to achieve opening and closing control, when supporting the electric actuator should first choose the electric actuator according to the type of valve.
QOTO’s electric actuator is divided into: Multi-turn series electric actuator and quarter-turn series electric actuator According to the angle of rotating valve plate. If you want to Lifting type then the straight stroke series of electric actuators is also a good choice.
The pressure, diameter, temperature, applicable environment and media are also taken into account when selecting an electric actuator to match the valve.
In addition, QOTO’s electric actuators are available in several control options. It has on-site control, that is, when the “mode selector knob” is in the “site”, the “operating knob” or “infrared setter” can be used to control the opening or closing of the valve. Remote switch control, also called remote manual control. When the “mode selection knob” is “far away”, the switch quantity control has three inputs, namely valve opening, valve closing, stop/holding; the switch control can be controlled by “hold” or “jog” mode through external wiring. Remote current quantity control (also known as remote automatic control): When the “mode selection knob” is “far away”, the user can control the operation of the actuator through 4~20mA current quantity to achieve precise positioning of the valve. ESD Control: In an emergency, the ESD signal can override any field and remote signals, allowing the actuator to be forced to close or open. ESD can be selected to be active high or low, or to override the motor overheat or override mode in the stop position or to override the intermittent operation control.
Fieldbus control (also known as remote digital control): PT series actuators have the ability to accept fieldbus control. The actuator can realize the control requirements of Profibus-DP bus and Modbus bus. For this function, please specify when ordering. Two-wire control: The PT series actuators feature two-wire electric operation. It can realize the special control requirements of “with signal on, no signal off” and “with signal off, no signal on”. Intermittent operation control: Intermittent operation means that the operation of the actuator is not continuous. This operation is set for those that need to be moved during the opening or closing of the valve. Intermittent operation allows the actuator to perform the closing/opening action in a pulsating manner, which effectively increases the travel time to prevent hydraulic shock and fluid surge.