Mercedes-Benz Air Conditioning Pressure Sensor 2038211592

Pressure sensor is the most commonly used sensor in industrial practice, which is widely used in various industrial automatic control environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automatic control, aerospace, military industry, petrochemical, oil wells, electric power, ships, machine tools, pipelines and many other industries. And in different environments, different types of pressure sensors need to be used to avoid errors.

Working principles of different pressure sensors

1. Piezoresistive force sensor: Resistance strain gauge is one of the main components of piezoresistive strain sensor. The working principle of metal resistance strain gauge is the phenomenon that the strain resistance adsorbed on the base material changes with mechanical deformation, commonly known as resistance strain effect.

2. Ceramic pressure sensor: The ceramic pressure sensor is based on piezoresistive effect, and the pressure directly acts on the front surface of the ceramic diaphragm, resulting in slight deformation of the diaphragm. Thick film resistors are printed on the back of the ceramic diaphragm and connected to form a Wheatstone bridge. Due to piezoresistive effect of the piezoresistive resistor, the bridge generates a highly linear voltage signal proportional to the pressure and also proportional to the excitation voltage. The standard signal is calibrated as 2.0/3.0/3.3 mv/according to different pressure ranges.

3. Diffused silicon pressure sensor: The working principle of diffused silicon pressure sensor is also based on piezoresistive effect. By using piezoresistive effect principle, the pressure of the measured medium directly acts on the diaphragm (stainless steel or ceramic) of the sensor, causing the diaphragm to generate micro-displacement proportional to the pressure of the medium, so that the resistance value of the sensor changes. This change is detected by electronic circuit, and a standard measurement signal corresponding to this pressure is converted and output.

4. Sapphire pressure sensor: Based on the working principle of strain resistance, silicon-sapphire is used as a semiconductor sensitive element, which has unparalleled measurement characteristics. Therefore, the semiconductor sensor made of silicon-sapphire is insensitive to temperature change and has good working characteristics even at high temperature. Sapphire has strong radiation resistance; In addition, the silicon-sapphire semiconductor sensor has no p-n drift.

5. Piezoelectric pressure sensor: Piezoelectric effect is the main working principle of piezoelectric sensor. Piezoelectric sensor can not be used for static measurement, because the charge after external force is preserved only when the loop has infinite input impedance. This is not the case in practice, so it is decided that the piezoelectric sensor can only measure dynamic stress.