There are three main types of pressure sensors: gauge pressure sensors, absolute pressure sensors, and differential pressure sensors.
- Gauge pressure sensors measure the pressure relative to the atmospheric pressure. This means that the zero point for a gauge pressure sensor is the atmospheric pressure. Gauge pressure sensors are commonly used to measure the pressure of gases and liquids in closed systems. For example, gauge pressure sensors are used in car tires, hydraulic systems, and air conditioners.
- Absolute pressure sensors measure the pressure relative to a vacuum. This means that the zero point for an absolute pressure sensor is a perfect vacuum. Absolute pressure sensors are commonly used to measure the pressure of gases and liquids in open systems. For example, absolute pressure sensors are used in weather balloons, scuba diving equipment, and vacuum pumps.
- Differential pressure sensors measure the difference in pressure between two points. This means that the zero point for a differential pressure sensor is the average of the two pressures being measured. Differential pressure sensors are commonly used to measure the flow rate of fluids, the pressure drop across a filter, and the pressure difference between two chambers in a machine.
In field automation, pressure sensors are used in a variety of applications, including:
- Level measurement: Pressure sensors can be used to measure the level of liquids or solids in tanks or vessels.
- Flow measurement: Pressure sensors can be used to measure the flow rate of fluids through pipes or channels.
- Pressure control: Pressure sensors can be used to control the pressure of gases or liquids in a system.
- Safety monitoring: Pressure sensors can be used to monitor the pressure of gases or liquids in a system and to warn of potential hazards.
- Quality control: Pressure sensors can be used to monitor the quality of products or processes.
The specific type of pressure sensor used in a particular application will depend on the specific requirements of the application.
Here are some additional details about gauge pressure sensors, absolute pressure sensors, and sealed gauge pressure sensors:
- Gauge pressure sensors are the most common type of pressure sensor. They are relatively inexpensive and easy to use. However, they are not as accurate as absolute pressure sensors.
- Absolute pressure sensors are more accurate than gauge pressure sensors. However, they are also more expensive and complex.
- Sealed gauge pressure sensors are a type of gauge pressure sensor that has a sealed reference chamber. This means that the sensor is not affected by changes in atmospheric pressure. Sealed gauge pressure sensors are often used in applications where the atmospheric pressure is not constant, such as in high-altitude environments.
