Spirax Sarco’s EP5 and PP5 control valve positioners operate on the balanced forced principle providing a tested solution for accurate control valve positioning. Both types are simple to commission and maintain with a low air consumption and 0,2 to 1,0 bar and 4-20 mA input signal options.
The positioners are used with linear pneumatic actuators; comparing the output signal from a pneumatic controller (or transducer) with the valve position feedback, and varying the pneumatic output signal to the actuator accordingly. The valve position is, therefore, guaranteed for any controller output signal and the effects of varying valve differential pressure, stem friction and diaphragm hysteresis are overcome. The positioners can also be used where the controller output signals are of too low a magnitude to be used directly with high pressure actuators. A mounting kit is supplied for fitment to either columns or yoke in accordance with NAMUR standard. Safety covers are also provided.
The positioners can be used with Spirax Sarco’s actuator types PN9000 and TN2000 series, if required an intrinsically safe version is available.