DE49_A Differential Pressure Transmitter

The differential pressure transmitter DE49 allows the measurement of under-pressure, over-pressure and differential pressure in liquid and gaseous media. Fields of application include tankers and fuelling systems. The DE49 is suitable as an electrical device for operation in potentially explosive areas. The multifunctional differential pressure transmitter with 2-conductor technology allows the measurement of under-pressure, over-pressure and differential pressure in liquid and gaseous media. The basis is a piezoresistive pressure sensor that is attached to a base with glass openings on the inside of a metal case. The pressures that are to be compared are fed to the inner and outer side of the sensor membrane via a pressure transfer liquid. The separating membranes transfer the medium pressure to the pressure transfer liquid. Piezo resistors are diffused into the silicone membrane. The force resulting from the differential pressure changes acts on the membrane and changes the resistance. This is measured and processed by the analysis electronics. The measured value is shown on the LC display and illustrated as an analogue 4-20 mA signal in the supply circuit.