Fisher Controls EMERSON Valve Positioner 3582. Fisher 3582 pneumatic valve positioners are used with diaphragm-actuated, sliding-stem control valve assemblies. This pneumatic valve positioner receives a pneumatic input signal from a control device and modulates the supply pressure to the control valve actuator, providing an accurate valve stem position that is proportional to the pneumatic input signal. BRAND NEW, BOX OPENED FOR DETAILED PICTURES. Any questions, please don't hesitate contacting us.