How to use a multimeter to perform a simple test on the pressure sensor

　　Pressure sensors are a type of pressure instrument . They are usually tested after they are produced. Some customers are used to testing the pressure sensors themselves, but they usually do not have systematic devices for testing. They usually use a multimeter for simple testing. How to use a multimeter for simple testing?

　　Multimeter to detect pressure sensor

　　Using a multimeter to test the pressure sensor can only perform simple tests, and the test results are for reference only. There are roughly three tests that can be performed: bridge circuit test, which mainly tests whether the sensor circuit is correct, generally a Wheatstone full bridge circuit, using the ohm range of the multimeter to measure the impedance between the input terminals and the impedance between the output terminals. These two impedances are the input and output impedances of the pressure sensor.

　　If the impedance is infinite, the bridge is disconnected, indicating that there is a problem with the sensor or the pin definition is not correct. To detect the zero point, use the voltage range of the multimeter to detect the zero point output of the sensor without applying pressure. This output is generally a voltage of mV level. If it exceeds the technical indicators of the sensor, it means that the zero point deviation of the sensor is out of range.

　　The method of pressure test is: power the sensor, blow the air hole of the pressure sensor with your mouth, and use the voltage range of the multimeter to detect the voltage change at the output end of the sensor. If the relative sensitivity of the pressure sensor is large, the change will be obvious. If there is no change at all, you need to use a gas pressure source to apply pressure.

　　The above methods can basically detect the general condition of a pressure sensor. If accurate detection is required, a standard pressure source is needed to apply pressure to the sensor and calibrate the sensor according to the pressure and the change in the output signal. If conditions permit, temperature detection of related parameters can be performed.

　　In short, the detection of pressure sensors is a responsible task. A multimeter can be used for general detection, which is applicable in many cases. However, if the pressure sensor is required to be used in a strict environment, a systematic detection must be carried out.