In modern technology and industrial applications, pressure sensors play an important role as important measurement tools. Among them, gauge pressure sensors, differential pressure sensors and absolute pressure sensors are the three core sensors in the field of pressure measurement due to their unique functions and wide range of applications. この論文では, we will discuss in depth the definitions, operating principles, measurement objects, application scenarios, and the differences between these three sensors.
目次
Gauge Pressure Sensor
Definition and Operation Principle
A gauge pressure sensor is a sensor that measures the relative pressure, i.e. the pressure value relative to atmospheric pressure. It usually consists of a sensing element (例えば. a strain gauge or piezoresistive element) and an electronic circuit that converts the pressure into a telecommunication signal. When external pressure is applied to the sensing element, the element undergoes a small deformation, resulting in a change in the resistance value, which is measured by the electronic circuit and converted into a telecommunication signal related to the pressure.
Operation Principle
Gauge pressure sensors are based on atmospheric pressure, and pressure readings are relative to the difference in atmospheric pressure. 例えば, if the sensor displays a value of 5 bar, then the actual pressure is 5 bar higher than the atmospheric pressure.
Measurement Objects and Applications
Usually used in applications where relative pressure is required, such as water pressure, ガス圧, liquid pressure, fluid control, level measurement etc. 例えば, in chemical plants, gauge pressure sensors can be used to measure pressure in pipelines to ensure that operations are carried out within safe limits. In automobiles, gauge pressure sensors are often used to measure tire pressure to provide drivers with information about the condition of their tires. In consumer electronics, gauge pressure sensors are used in areas such as pressure change monitoring, environmental adaptation, and health monitoring. They provide important functions such as altitude measurement, weather change alerts, airflow monitoring, 等々.
Features:
- Based on changes in atmospheric pressure.
- If atmospheric pressure changes, the gauge pressure sensor reading is unaffected.
- Suitable for common industrial applications such as gas systems, hydraulic systems.
差圧センサー
Definition and Operation Principle
Differential pressure sensor is a sensor that measures the pressure difference between two measurement chambers. It measures the pressure difference between two different points. It is not concerned with the pressure of these pressure points relative to the atmosphere, but only with the difference between them. It usually consists of two chambers connected to the medium to be measured, and the pressure is determined by measuring the pressure difference between the chambers. The principle of operation of the differential pressure sensor is based on the pressure to be measured directly on the diaphragm of the sensor, so that the diaphragm produces a micro-displacement proportional to the water pressure, which in turn causes a change in the value of the resistance, the electronic circuit detects this change and converts it into a standardized measurement signal corresponding to the pressure.
Operation Principle
Differential pressure sensor outputs a value for the relative differential pressure by simultaneously measuring the pressure at two points and calculating the difference between them. 例えば, at both ends of a pipeline, a differential pressure sensor can measure the pressure difference, which is commonly used for flow measurement and filter clogging detection.
Measurement Objects and Applications
Differential pressure sensors are widely used in flow measurement, liquid level measurement, gas analysis and other fields. In HVAC systems, differential pressure sensors are often used to measure the clogging of air filters so that they can be replaced in a timely manner. 加えて, differential pressure sensors are also used to measure the difference in exhaust gas pressure between the front and rear passages of a vehicle’s engine particle trap to determine the level of particle buildup in the trap, which in turn determines the trigger time for “regeneration” and the amount of additional fuel to be injected.
Features:
- Ideal for monitoring the pressure difference between two points.
- Used for flow calculations, wind speed measurements, 等.
- Compares the pressure difference between two points, ignoring the effect of atmospheric pressure.
絶対圧センサー
Definition and Operation Principle
An absolute pressure transducer is a transducer that measures pressure relative to a vacuum or absolute zero. Unlike gauge pressure sensors, absolute pressure sensors not only measure the pressure of the measured medium, but also take into account the gas pressure in the environment. Absolute pressure sensors work similarly to gauge pressure sensors, but their reference point is absolute vacuum or absolute zero rather than atmospheric pressure. Or the pressure of a completely pressure-free state. It is based on absolute zero pressure (vacuum) and is not affected by atmospheric pressure.
Operation Principle
The absolute pressure sensor measures the absolute pressure of a gas or liquid, and its reading always includes the effect of atmospheric pressure. Even if the atmospheric pressure changes, the reading of the absolute pressure sensor will reflect the absolute pressure.
Measurement objects and applications
Absolute pressure sensors are widely used in atmospheric pressure measurement, high-altitude meteorological observation, weather forecasting and other fields. 医療分野では, absolute pressure sensors are used to monitor the gas pressure in respirators. 加えて, absolute pressure sensors are also used to measure intake air pressure to optimize engine performance and fuel economy.
Features:
- Measures pressure compared to vacuum, taking into account changes in atmospheric pressure.
- The use of absolute pressure sensors is particularly important in specific environments, such as applications with high altitude variations.
- Used in high-end applications requiring precise pressure monitoring, such as aerospace, meteorological monitoring, vacuum technology.
Differences between the three types of sensors
1. Measurement Object:
- Gauge pressure sensors measure pressure relative to atmospheric pressure.
- Differential pressure sensors measure the pressure difference between two measurement chambers.
- Absolute pressure sensor to measure the pressure value relative to the vacuum.
2. Measurement principle:
- Surface pressure sensors use absolute pressure sensors and atmospheric pressure sensors to measure and calculate the surface pressure by calculating the difference between the absolute pressure and the atmospheric pressure.
- Differential pressure sensors use two pressure sensors to measure the pressure difference between two locations.
- Absolute pressure sensors use absolute pressure sensors to measure and subtract the atmospheric pressure from the measurement result to obtain the absolute pressure.
3. Measurement range:
- Gauge pressure sensors usually have a large measuring range and can measure both high and low pressures.
- Differential pressure sensors are usually used for smaller differential pressure measurement ranges.
- Absolute pressure sensors have a measurement range that depends on the specific application, but usually requires consideration of the vacuum condition.
4. Application Scenarios:
- Gauge pressure sensors are commonly used in industrial automation, automotive industry, medical equipment and other fields.
- Differential pressure sensors are widely used in flow measurement, liquid level measurement, gas analysis and other fields.
- Absolute pressure sensors are more focused on atmospheric pressure measurement, high altitude meteorological observation and other applications that require accurate pressure measurement.
結論
Gauge pressure sensors, differential pressure sensors and absolute pressure sensors are the three core sensors in the field of pressure measurement, each with their own unique functions and a wide range of applications. Through a deep understanding of their operating principles, measurement objects and application scenarios, we can better select and use these sensors to meet the measurement needs of different fields. As technology continues to develop, the performance and accuracy of these sensors will continue to improve, providing more reliable and accurate measurement data for industrial production and scientific research.
