Key Parameters & Specifications Parameter / Feature Category Description Product Name Fisher™ 480 Series Pneumatic Valve Positioner Type Force-Balance, Pneumatic (I/P) Primary Function To accurately position a control valve stem in proportion to a pneumatic input signal. Input Signal Standard: 3-15 psi (0.2-1.0 bar) or 6-30 psi (0.4-2.0 bar). Other ranges are available. Output Signal (to Actuator) Supply pressure dependent. Provides the necessary air pressure to the actuator to achieve and hold the required valve position. Supply Pressure Typically up to 100 psig (7 bar) for the 48000 model. Other models may vary. Must be at least 3-5 psi above the input signal and actuator pressure requirements. Action Field-reversible between direct and reverse. • Direct: Input signal increase extends stem (for air-to-open valves). • Reverse: Input signal increase retracts stem (for air-to-close valves). Air Consumption Low, typically around 0.15 SCFM (4 standard liters/min) at steady state. Flow Capacity (Relay) High-capacity relay allows for rapid filling and exhausting of the actuator. Typical exhaust capacity is >1.0 SCFM (28 standard liters/min). Mounting Direct-mounted on the valve yoke, with a mechanical feedback linkage connected to the valve stem. Enclosure Generally, a weatherproof and corrosion-resistant aluminum enclosure. Approvals Suitable for use in hazardous areas due to its purely pneumatic nature. Typical Models 48000 (general purpose), 48001, 48002, etc., with variations for specific actuator types and linkages.
