Setra’s Model 239 series of pressure transducers are specifically designed for very low pressure applications that require high accuracy. Setra’s variable capacitance sensor is designed to be simple and reliable. A stainless steel diaphragm and an insulated electrode form a variable capacitor. As pressure increases or decreases, the capacitance changes. This change in capacitance is detected and converted to a linear D.C. electric signal by Setra’s unique electronic circuit. The Model 239 provides a high level voltage output. The C239 provides a 4-20 mA current output. High positive overpressure protection is achieved by the sensor electrode acting as a stop for the diaphragm. The high level output signals, excellent long term stability and fast dynamic response make these transducers ideal for a wide range of industrial, laboratory and aerospace applications.