Pantech Instruments manufactures Microcontroller Based Valve Positioner, Model 883. Pantech Instruments is the manufacturer and exporter of Process Control Instruments. Microcontroller Based Valve Positioner is designed to control output going to servo valve, with or without the process controller. It is a panel mounted Control Valve Driving Station, which accepts 4 - 20mA signals from controller and a feedback signal from control valve. The voltages for feedback signal are derived from the Microcontroller Based Valve Positioner itself. The Microcontroller Based Valve Positioner generates up or down pulses to operate motorized control valve based on the difference between controller output and feedback from control valve. The specially designed circuit drives the instrument in Manual mode, in case of input or feedback failure and locks the valve in its last position. Variable dead band of 0.5 percent to 5.0 percent prevents the valve from hunting. Microcontroller Based Valve Positioner is also available while delaying the movement of valve by preset time once it is settled. The instrument has an overriding facility through the valve can be driven up or down manually. The Microcontroller Based Valve Positioner displays valve opening in percentage through 4-digit red LED display.
