A pressure sensor (also known as a pressure transducer) is a device that can detect pressure signals and convert them into usable electrical signals in a defined manner. It typically consists of a pressure-sensitive element and a signal processing unit.
The core components are the sensing element and the conversion element, with the sensing part usually made of pressure-sensitive materials. When external pressure is applied to the sensor, the sensing element deforms, and this deformation is converted by the conversion unit into a corresponding electrical signal, completing the process of translating physical pressure into an electrical output. Many distributors offer a wide range of electronic components to cater to diverse application needs, like 425-00-00-872
Working Principle and Types of Pressure Sensors
Depending on the measurement principle, pressure sensors can be categorized into various types.
The piezoresistive pressure sensor is one of the most common. It works by detecting changes in resistance when the sensing element is under pressure, and the pressure value is calculated by measuring this change.
Capacitive pressure sensors measure pressure by detecting changes in capacitance caused by the applied pressure.
Piezoelectric pressure sensors use piezoelectric materials that generate an electric charge when compressed, making them suitable for dynamic measurements due to their fast response and high sensitivity.
Fiber optic pressure sensors measure pressure by detecting changes in light signals caused by pressure-induced deformation of the optical fiber; they offer strong resistance to electromagnetic interference, high measurement accuracy, and long transmission distances.
There are also magnetoelectric pressure sensors that measure pressure by detecting changes in the magnetic field caused by pressure, featuring simple structure, wide measurement range, and strong anti-interference capability.
Classification of Pressure Sensors
In practical applications, pressure sensors can be divided by the type of pressure they measure: gauge pressure sensors, differential pressure sensors, and absolute pressure sensors. They can also be classified by working principle and material into types such as resistive, inductive, resonant, and voltage-type pressure sensors, which include strain gauge types, piezoresistive types, variable inductance types, and diaphragm box types.
Application Fields of Pressure Sensors
Pressure sensors are widely used for automated monitoring and control in industrial production and daily life, making them one of the most common sensors in the industrial sector.
For example, in hydraulic systems, they are used for force closed-loop control. In safety control systems, they help improve the accuracy of compressors by monitoring pipeline pressure. In injection molding, pressure sensors can be installed in nozzles, hot runners, or mold cavities to measure plastic pressure in real time during injection, filling, holding, and cooling. In mining safety, different types of mining pressure sensors are used to monitor underground pressure and ensure production safety.
Key Points for Selecting a Pressure Sensor
When selecting a pressure sensor, it is important to consider factors such as measuring range, accuracy, lateral force resistance, packaging, output signal type, and the working environment. The actual measured pressure must fall within the sensor’s range, and it is advisable to reserve a margin of 10%–30% to avoid overload, which could damage the sensor or shorten its lifespan. Generally, for the same model, the smaller the measuring range, the higher the measurement accuracy.
Main Performance Parameters of Pressure Sensors
Key performance parameters include rated pressure range, maximum pressure capacity, burst pressure, linearity, pressure hysteresis, operating temperature range, zero-point temperature coefficient, full-scale temperature coefficient, protection rating, and power supply requirements.
Future Development Trends
In recent years, with advancements in semiconductor and MEMS technologies, pressure sensors have been evolving toward miniaturization, low power consumption, high reliability, and high precision. The application of multi-sensor information fusion is also pushing pressure sensors toward greater intelligence. As a core tool in modern measurement and control systems, pressure sensors play an indispensable role in various fields, including industry, transportation, energy, and aerospace. Understanding their working principles and applications is crucial for selecting the right product and using it effectively.