Fisher 4320 Pneumatic Valve Positioner

Technical Specifications

Model：4320 Brand：Fisher Product Type: Pneumatic valve positioner

Module Feature

Fisher 4320 is force-balance pneumatic positioner for linear and rotary actuators. It receives 3~15psi pneumatic signal and adjusts output air pressure to drive actuator for accurate valve positioning. It supports single-acting and double-acting configuration, zero/span adjustment and direct/reverse action switch. Low deadband and stable performance under vibration. Widely used in oil,gas,chemical and power plant globe and rotary control valves.

Working principle: Pneumatic force balance feedback control Onboard components: Nozzle-flapper assembly, pneumatic relay, feedback cam, pressure gauge ports, gaskets

LED indicators

Not equipped

Hardware self-diagnosis

Supply air pressure inspection, zero & span calibration, full stroke test, air tightness leakage test

Programming software

No dedicated software required

Pneumatic Parameters

Input signal:3~15psi pneumatic signal Supply air:20~150psi Application:Linear and rotary pneumatic actuators

Mechanical & Structure

Mounting:Direct mount on Fisher valve actuators Protection class:IP54

Environmental

Operating temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non-condensing Certification:CE,ATEX,IECEx Status:Fisher 4300 series pneumatic positioner

System compatibility

Compatible with Fisher 657,658,670 series pneumatic actuators and globe/rotary control valves for industrial process control system.

Function

4320 is pneumatic valve positioner manufactured by Fisher. It compares pneumatic setpoint signal with actual valve stem position and continuously adjusts output air pressure to eliminate position error. It realizes fast response and high repeatability for modulating control loop. It can be switched between direct and reverse action for different process requirements. It is widely used for industrial control valve positioning.

Installation

Follow lockout/tagout safety procedure before installation. Cut off instrument air supply. Mount positioner on valve actuator, connect instrument air tubing and 3-15psi signal pipeline. Perform zero and span calibration and full stroke test. Restore air supply and run valve function and leakage inspection.

Interface

1/4"NPT pneumatic ports, pressure gauge ports, mounting bracket, no LED indicators on 4320.

Diagnostic

Valve no movement: Loss of supply air or blocked signal pipeline. Poor positioning accuracy: Zero/span drift or cam wear. Air leakage: Damaged gasket or loose pipe fitting.

Product Brief

4320 Fisher pneumatic valve positioner,used for industrial linear/rotary control valve actuator positioning with 3-15psi pneumatic input signal,pneumatic positioner spare part.