A pressure sensor is a device for pressure measurement of gases or liquids. Pressure is an expression of the force required to stop a fluid from expanding, and is usually stated in terms of force per unit area. A pressure sensor usually acts as a transducer; it generates a signal as a function of the pressure imposed. For the purposes of this article, such a signal is electrical.
What is the working principle of a pressure sensor? A pressure sensor works by converting pressure into an analogue electrical signal.
The demand for pressure measuring instruments increased during the steam age. When pressure sensing technologies were first manufactured they were mechanical and used Bourdon tube gauges to move a needle and give a visual indication of pressure. Nowadays we measure pressure electronically using pressure transducers and pressure switches.
Static Pressure
Pressure can be defined as force per unit area that a fluid exerts on its surroundings. The basic physics of static Pressure (P), is calculated as force (F) divided by area (A).
P=F/ A
The Force can be generated by liquids, gases, vapours or solid bodies.
The most commonly used pressure units are;
Pa – [Pascal] in 1 Pa = 1 (N/m²)
Bar – [Bar] in 1 bar = 105
psi: (pound (-force) per square inch)
Working Principle of a Pressure Sensor
What does the pressure sensor work? Pressure transducers have a sensing element of constant area and respond to force applied to this area by fluid pressure. The force applied will deflect the diaphragm inside the pressure transducer. The deflection of the internal diaphragm is measured and converted into an electrical output. This allows the pressure to be monitored by microprocessors, programmable controllers and computers along with similar electronic instruments.
Most Pressure transducers are designed to produce linear output with applied pressure.
What are pressure sensors used for? Pressure sensors are used in a range of industrial application, including the automotive industry, medical applicaion, aviation and the marine industry, to name a few.