Pressure sensors are instruments equipped with pressure sensitive elements used in determining the actual amount of pressure that is applied. They utilize different principles to do this. The collected information is often translated into electrical output signals. More specifically, pressure sensors are used to measure the pressure of liquids or gases. They typically function as transducers, which mean they are equipped with pressure-sensitive elements.
Pressure sensors are known by many names. They are also called as pressure transmitters, pressure transducers, pressure indicators, pressure senders, manometers, and piezometers. They come in different designs and vary according to cost, performance, technology, and application suitability.
Some pressure sensors can capture extremely high-speed pressure changes, like when calculating combustion pressure in a gas turbine. Pressure sensors can function as pressure switches as well, as in the case of a water pump that’s controlled by a pressure switch so it can release water.
Pressure sensors display pressure in different units, the most common of which are Pounds per Square (PSI), Bar, and Pascal. Typical signals used by pressure sensors are 0-5 Volts and 4-20 milliamps.
There are different types of pressure that are measured using pressure sensors. The three that are commonly used are absolute pressure, gauge pressure, and differential pressure.
- Absolute pressure is the type that is calculated against absolute vacuum. It is ideal for pressure readings that are lower than atmospheric pressure.
- When using atmospheric pressure as reference for measuring, the suitable sensor type is gauge pressure. Atmospheric pressure value is usually placed at 14.7 PSI. A negative pressure goes below atmospheric pressure, and positive pressure goes above atmospheric pressure.
- Differential pressure refers to the difference between a referenced pressure and measured pressure.
Pressure sensors are used for various applications and industries. Some examples are pressure sensing, flow sensing, altitude sensing, depth sensing, steam systems, leak testing, level measurement, and filters.