Choosing the right pressure sensor for a specific application requires considering many factors, which are detailed below:
Select based on the characteristics of the measuring medium
corrosive media
When measuring the pressure of corrosive media such as acid, alkali, and salt solutions, pressure sensors made of corrosion-resistant materials should be selected, such as sensors with housings and diaphragms made of materials such as stainless steel 316L or Hastelloy.
For example, in monitoring acid-base neutralization reactions in chemical production, sensors made of ordinary materials are quickly corroded and damaged, while pressure sensors with Hastelloy housings and tantalum diaphragms can work stably for a long time.
viscous media
For viscous media such as glue, paint, and syrup, a diaphragm pressure sensor should be selected. Its diaphragm can effectively isolate viscous substances, preventing them from entering the sensor and affecting measurement accuracy or damaging the sensor.
For example, when measuring the pressure of syrup in food processing, using a diaphragm pressure sensor ensures accurate measurements and is easy to clean and maintain.
High temperature medium
To measure the pressure of high-temperature media, such as the pressure inside a furnace or boiler, a high-temperature resistant pressure sensor is required. Its internal sensitive element and housing must be able to withstand high temperatures.
Generally, pressure sensors using ceramic sensing elements and stainless steel housings can operate normally at temperatures up to 400°C, meeting the needs of most high-temperature scenarios.
Determined based on the measurement range
Low-voltage measurement scenarios
In vacuum coating processes for manufacturing microelectromechanical systems (MEMS), extremely low pressure needs to be measured. In such cases, a micro differential pressure sensor should be selected, which can accurately measure minute pressure changes of a few Pascals or even a fraction of a Pa.
Medium pressure measurement range
In ordinary industrial pipeline fluid pressure measurement, such as urban water supply pipeline pressure measurement, the pressure range is usually between 0.1MPa and 1MPa, and conventional pressure sensors can meet the requirements.
High voltage measurement applications
For example, in high-pressure hydraulic systems or deep-sea pressure measurement scenarios, the pressure may be as high as tens or even hundreds of megapascals, requiring the use of high-pressure sensors that can withstand and accurately measure such high pressures.
Select according to accuracy requirements
High precision requirements
In aerospace flight control systems, extremely high pressure measurement accuracy is required, necessitating the selection of pressure sensors with an accuracy class of 0.1% or even higher to ensure flight safety and control accuracy.
General accuracy requirements
In some common industrial production process control, such as the pressure forming process in building materials production, the requirements for pressure accuracy are relatively low. Pressure sensors with an accuracy level of 0.5% to 1% can usually meet the production needs.
Consider working environment conditions
Harsh environment
If used in harsh environments with high dust levels, such as mines and construction sites, choose a pressure sensor with a high protection rating, such as IP65 or higher, which can effectively prevent dust and water damage.
In addition, if flammable and explosive gases are present, explosion-proof pressure sensors must be selected. Intrinsically safe pressure sensors, for example, can work safely in hazardous environments.
Vibration and shock environments
On equipment subject to vibration, such as automotive engine test benches, pressure sensors with good vibration resistance should be selected. Their internal structure and installation method can withstand a certain degree of vibration and impact, reducing measurement errors.
Considering installation requirements and space constraints
Installation method
For pipeline installations, threaded or flanged pressure sensors are typically selected; in some special locations, such as confined spaces, compact welded or compression fitting pressure sensors may be necessary.
Space constraints
In small electronic devices such as smartphones, air pressure needs to be measured. Due to limited internal space, miniaturized pressure sensors must be selected, which are small in size but meet the performance requirements.
Based on signal output and compatibility
Signal output type
If subsequent equipment or systems can only receive analog signals, such as some traditional industrial control instrument panels, then a pressure sensor that outputs a 4-20mA analog current signal should be selected.
For pressure sensors that are connected to digital systems, such as automated control systems in smart factories, digital signals such as SPI and I2C can be selected for easy system integration and data transmission.
compatibility
Pressure sensors must be compatible with other equipment and software within the system, including power supplies, communication protocols, and data acquisition devices. In automated production lines, various devices need to work collaboratively, and pressure sensors must be highly compatible with PLCs, industrial computers, and other equipment to ensure the stable operation of the entire system.
