The environmental factors affecting sensors mainly include the following:
High-temperature environments can cause problems such as melting of coating materials, opening of solder joints, and structural changes in the internal stress of the elastic body of the sensor. For sensors operating in high-temperature environments, high-temperature resistant sensors are often used; in addition, heat insulation, water cooling, or air cooling devices must be added.
Dust and humidity can cause short circuits in sensors. In these environmental conditions, sensors with high sealing performance should be selected. Different sensors have different sealing methods, and their sealing performance varies greatly. Common sealing methods include sealant filling or coating; mechanical fastening with rubber gaskets; welding (argon arc welding, plasma beam welding) and vacuum nitrogen filling. From the perspective of sealing effect, welding sealing is the best, while sealant filling and coating is the worst. For sensors working in clean and dry indoor environments, sensors with adhesive sealing can be selected, while for sensors working in humid and dusty environments, diaphragm heat-shrink sealing or diaphragm welding sealing, and vacuum nitrogen-filled sensors should be selected.
In highly corrosive environments, such as humid and acidic environments, which can cause damage to the elastic body or short circuits in the sensor, sensors with a sprayed plastic or stainless steel outer casing, good corrosion resistance, and good sealing performance should be selected.
Electromagnetic fields can cause chaotic signals in the sensor output. In this case, the shielding performance of the sensor should be strictly checked to see if it has good anti-electromagnetic interference capabilities.
Flammable and explosive environments not only cause complete damage to the sensor but also pose a great threat to other equipment and personal safety. Therefore, sensors working in flammable and explosive environments require higher explosion-proof performance: in flammable and explosive environments, explosion-proof sensors must be used. The sealed outer casing of such sensors must consider not only its sealing performance but also its explosion-proof strength, as well as the waterproof, moisture-proof, and explosion-proof properties of the cable leads.