In almost every type of system or application where gases or liquids are present, there would be strategic places where the pressure of those gases or liquids has to be measured. With this specific type of measurement, a low pressure sensor is often the best choice as it can record even slight variations in pressure with the required degree of accuracy based on the application.
For example, a simple tire pressure gauge is a form of a low pressure sensor that measures the air pressure in the tire in relationship to the atmospheric pressure. They are a simple read the gauge type of sensor without the need for electronics, but they are accurate to the degree required for safe operation of vehicles.
The Electronic Component
For more advanced and complex measurements within a system, or when readings are required on a continual or frequent basis, the simple pressure sensor can be developed to read the pressure and convert it to an electrical signal. This forms the basis of managing and controlling these systems, as all actions can be automated based on these readings.
Depending on the type of pressure sensor different components such as strain gauge technology, piezoelectric or variable capacitance, can be used to create the change that is registered by the sensor and converted into an electric signal. This electric signal, either voltage or current, is then read by the system and converted into a digital readout to be visually displayed or relayed into a computer system or printer for constant monitoring.
Considerations
As with any other type of component, it is essential to match the low pressure sensor design and capacity to the specific application. It is possible to easily overload a pressure sensor which will result in failure of the system to provide accurate readings.
Liquids are most problematic for this overload concern. A pressure change known as a water hammer phenomenon can easily occur. This is more common in high pressure systems, but to a lesser degree, it can happen in any system.
As the liquid is moving through the system and a valve is suddenly closed, the pressure changes in the line and the water can hit the pressure sensor with additional force. This creates a sudden and dramatic increase in pressure that can affect the future operation of the sensor. If this is repeated often the pressure sensor, particularly if not protected, will become less effective over time.
