Elektropneumatischer Umformer mit analogem Ausgang

摘要

An electro-pneumatic pressure transducer is provided with a valve body assembly having a supply chamber, an exhaust chamber and an intake assembly to provide a source of fluid to the transducer. The transducer also has an output assembly directing the fluid to a pneumatic actuator. The valve body further includes a supply valve assembly and an exhaust valve assembly having bender elements adjustably mounted to the valve body with respect to nozzles. A manifold structure is included for fluidly connecting the supply valve, the exhaust valve and the output assemblies. A pressure sensor is used to measure the pressure in the valve body and is responsive to increases or decreases of the pneumatic pressure in the valve body. A monitor is used to monitor the power source and to generate a failure mode signal when the power source fails to supply a predeternined level of power. A control, responsive signal generated by the sensor and the monitor, is included to move the bender elements to achieve a specified fluid pressure in the transducer. An independent fail-safe condition is also provided in the transducer to depressurize the transducer when power is absent for a predetermined period of time.