• Continental Valve Limited

Pneumatic Positioner & Motion Transmitter

Continental Valve Limited offers Pneumatic Positioner and Motion Transmitter, Model-3046. Positioners are instruments for pneumatic control valves and defined by VDI/VDE direction 2177.
Positioners serve the following purposes: Compensation of undesirable disturbance forces acting upon the control valve particularly in the case of high differential pressures and large unbalanced trim areas; improved accuracy of the positioning; split range applications; reduction of the stroking time; linearising or fixation of defined flow characteristics; output of high actuation pressures, which develop a much higher force in the control valve than possible in the standard pressure range; assignment of direction of movement and action to the safety conditions of the control valve range; and splitting of the output pressure into two oppositely oriented control signals (double action).
Principles of operation: The CVL positioner 3046 operates on the principle of balanced forces. The pneumatically pre-set control signal is compared with the motion distances that is transmitted via a cam, by a spring mounted on the so-called comparator lever. This comparator lever bears the adjusting knobs for zero point and stroke range. If the forces are unequal output pressure will change until the forces acting on the spring are balanced again.
Particular characteristics: Simple and solid construction; single action or double action; optional bypass system; reversibility of action; high static and dynamic amplification; amplification adjustable; high air supply; max supply pressure 6 bar; pressure gauge for input and output pressure in housing in standard equipment; linear and non-linear transmission characteristic due to interchangeable cam; mounting on control valves in accordance with Namur-recommendation; and requires minimum service.