The Fisher 846 transducer converts an electrical output signal from a controller to a pneumatic signal necessary to operate a control valve actuator or pneumatic positioner. Using electronic feedback, the transducer can correct for error-producing effects, such as variations in supply pressure and downstream leakage.
- The low-mass pilot stage, mechanically damped deflector bar, and rugged construction provide stable performance in vibration.
- Large diameter nozzles, free-flow pilot stage design, and large internal pneumatic supply passages provide excellent tolerance to reducing the effects of contaminant build-up and erosion.
- The electronic feedback control network monitors the pneumatic output signal, detects any input-output deviations and corrects them.
- Major mechanical and electrical components are incorporated into a single field-replaceable master module.
- With Stroke Port, a constant bleed from the pilot stage vents through a hole in the module cover. Covering the hole increases the transducer output to confirm the proper operation of the pilot and booster stages and stroke the actuator.