Description - The 3582 Series pneumatic valve positioners and the Type 3582i electro-pneumatic valve positioners, are used with diaphragm-actuated, sliding-stem control valve assemblies. The pneumatic valve positioners receive a pneumatic input signal from a control device and modulate the supply pressure to the control valve actuator, providing an accurate valve stem position that is proportional to the pneumatic input signal. For use on Fisher control valves.