Types of pressure systems
There are numerous different types of pressure sensing devices, with names that can be confusing to the uninformed and uninitiated. All of these terms are specific to variable capacitive sensing technologies, which handle the detection and measurement of fluid pressure through the change in voltage across a capacitor. Variable capacitance is used in applications that need an extremely high degree of accuracy, like engine test stands and pressure decay leak detection. The most common terms are sensors, transducers, transmitters, and switches, which we will explore in this blog.
A pressure sensor is any device that measures pressure and converts it into an electrical signal. It is an all-encompassing term that includes pressure transducers, transmitters, and switches, which we will define next. All transducers, transmitters, and switches are sensors, but not all sensors are transducers, transmitters, and switches.
Pressure transducers and transmitters are functionally similar. A pressure transducer is an electromechanical device that translates pressure values into voltages across a high-impedance load (5,000 ohms or greater). A transmitter, meanwhile, translates pressure valves into currents (usually between 4 and 20 mA) across a low-impedance load. In general, transmitters are preferred for long-range transmission (thousands of feet or more). Neither transmitters nor transducers control or change pressure, however. They are used purely to measure pressure and communicate changes via electronic or visual means.
Finally, a pressure switch will trigger at a specific set pressure. This pressure can be either high or low, and can engage or disengage a circuit. Pressure switches are unlike transducers and transmitters in that they can affect the pressure they detect. Pressure switches are commonly used in vehicles to indicate low engine oil pressure, and in gas compressors with an automatic shut-off mechanism.
At NSN Parts Now, owned and operated by ASAP Semiconductor, we can help you find all the pressure capacitance devices for the aerospace, civil aviation, and defense industries. We’re always available and ready to help you find all the parts and equipment you need, 24/7-365. For a quick and competitive quote, email us at sales@nsnpartsnow.com or call us at +1-714-705-4780.
