English 
engine oil pressure sensor working principle
Engine oil pressure sensor working principle: The sensor is installed next to the high-pressure common rail pipe, and the diesel oil flows to the common rail pressure sensor through the small hole on the common rail pipe to reach the diaphragm inside the sensor. Inside the sensor, a semiconductor element converts the pressure signal into an electrical signal. The signal generated by the sensor is amplified and sent to the detection circuit of ECU.
When the pressure in the common rail tube changes the shape of the diaphragm (when the pressure is 150MPa, the pressure is 1mm), the resistance layer connected to the diaphragm also changes, and the changed resistance value changes the output voltage of the 5v Wheatstone bridge. After being processed by the amplification circuit, the signal voltage changes between 0-5V, which is the pressure value in the common rail tube.Automobile air conditioner pressure switch: The pressure switch of automobile air conditioner is a pressure protection device set for the normal operation of the refrigeration system, including high voltage switch and low voltage switch.
1)High voltage switch
When the refrigeration system does not work properly or the refrigerant is added too much, the pressure in the air conditioning pipe will be too high, and the high pressure of the system will cause the condenser and high-pressure pipe to burst, the compressor exhaust valve and the electromagnetic clutch to be damaged, etc. When the system pressure reaches the upper limit, the high pressure switch will cut off the working circuit of the electromagnetic clutch, stop the compressor, and make the cooling fan of the condenser run at a high speed, reducing the pressure and temperature of the condenser. The high pressure switch is usually installed at the inlet of the liquid storage drying tank or the condenser.
2) Low voltage switch
The low pressure switch is installed on the liquid storage drying tank through threaded connection, which is used to sense the pressure on the high pressure side. When the pressure of the refrigerant discharged from the compressor is lower than 0.4 MPa or the temperature is lower (lower than 10 degrees), the low pressure switch will disconnect the circuit of the electromagnetic clutch to reduce the fuel consumption. The role of energy conservation.Conclusion: In addition to the several automobile pressure sensors listed above, there are many sensors used in other systems, such as collision system, electronic detection system, etc. Its main function is basically to convert pressure into voltage signal and output it to the control unit ECU.
Get a Quote / Info