What is the function and characteristics of differential pressure sensor
Differential pressure sensor, as the name implies, is a sensor, but it is used to transmit pressure difference, so it is called differential pressure sensor. Generally speaking, its function is mainly to measure the difference between two different pressures, and it is displayed through the sensor. The differential pressure sensor is often used to measure the pressure at the front and rear ends of a certain part of a device. poor value.
Characteristics of Differential Pressure Sensors
◇High performance price ratio
◇All stainless steel structure design, small size and light weight, easy to install
◇Stable and reliable performance
◇Differential pressure range: 0~10kPa.. .2 MPa
◇Static pressure resistance up to 20MPa
Typical Applications of Differential Pressure Sensors
It is used to measure the exhaust gas pressure difference between the front and rear channels of the automobile engine exhaust particulate filter (DPF).
In order to meet the requirements of emission standards, the usual method is to place a trap in the exhaust part of the vehicle to trap tiny particles in the exhaust gas. The disadvantage of this method is that the exhaust gas discharge channels gradually become clogged with the accumulation of trapped particles. The way to remove these accumulated particles is to increase the temperature of the exhaust gas by injecting additional fuel somewhere in the passage or directly in the exhaust gas. In the presence of a catalyst in the trap, the temperature of the exhaust gas is high enough to burn and gasify the accumulated particles. This cleaning process is known as the "regeneration" process. There is a problem in this process. Too frequent "regeneration" process will increase fuel consumption; if the interval is too long, it will reduce engine performance. Therefore, it is very important to choose a reasonable "regeneration" trigger time.
The differential pressure sensor sends the pressure difference signal to the ECU, and the ECU judges the degree of accumulation of particles in the trap based on the pressure difference, and determines the triggering time of "regeneration" and the amount of additional fuel injected. At the same time, the ECU can also adjust the temperature of the exhaust gas by controlling the EGR valve. In addition, differential pressure sensors can also be used to measure gas flow, liquid level, etc. The method of measuring gas flow, through the difference between the pressure of the flow tube and the atmospheric pressure, the static pressure of the flow tube is obtained, and the square root of the static pressure is proportional to the flow, so as to obtain the flow. The liquid level measurement method is to measure the pressure difference value of the high and low liquid level, and then convert the liquid level height according to the liquid density.
