Electro-pneumatic transducer 546

Fisher 546, 546S, and 546NS transducers receive a direct-current input signal and use a torque motor, nozzle-flapper, and pneumatic relay to convert the signal to a proportional pneumatic output signal. Nozzle pressure, which operates the relay, is also piped to the torque motor feedback bellows. This provides a comparison between input signal and nozzle pressure and corrects errors in nozzle pressure. Key Features High natural frequency of torque motor moving parts results in negligible vibration influence. Meets typical seismic requirements for nuclear service. Screw driver adjustments for span and zero are conveniently located and have arrows indicating rotation to increase settings. No additional are parts required to reverse action. Integrated pneumatic relay is mounted outside case and can be removed without disturbing electrical or pressure connections or impairing explosion safety.