How to measure the quality of sensors by professional third-party testing institutions

Date：2024-03-28 16:37:08 Views：179

Sensors are an indispensable part of modern technology, widely used in various fields such as automotive, aerospace, medical, industrial manufacturing, etc. However, as sensors are used for an extended period of time, they may malfunction or be damaged, leading to inaccurate or complete data failure. Therefore, how to measure the quality of sensors has become particularly important.

There are various types of sensors, including temperature sensors, pressure sensors, acceleration sensors, optical sensors, etc. Each sensor has its unique properties and working principle, so the testing methods are also different. The following are some common testing methods that can be used to measure the quality of sensors:

1. Fault symptom phenomenon judgment method

Based on the symptoms of faults and using experience to determine, it is the most intuitive and simple method to solve vehicle faults and determine the quality of sensors. But it has two drawbacks: first, it takes a long time to accumulate experience and cannot reach a high level in a short period of time; Secondly, the accuracy of the judgment results is low, and there is a high possibility of misjudgment.

2. Decoding detection method

Decoders are usually divided into original decoders and non original decoders. Reading and clearing fault codes is the main function of the decoder, so it is easy to determine the approximate direction and location of the fault, providing direction for sensor detection and troubleshooting.

3. Test light detection method

There are self-made testing lamps and specialized testing lamps for testing; It can come with or without a power supply. A self-made test light can be made by connecting a 300~500 Ω resistor in series with an external light-emitting diode (LED).

4. Multimeter detection method

When using a multimeter in cars, except for manual code adjustment and fault code reading in the early days, which required the use of a pointer type multimeter, it is generally not recommended to use a pointer type multimeter. Even when testing certain components, especially semiconductor components and related ECU circuits, it is emphasized that a digital multimeter must be used.

5. Oscilloscope detection method

Oscilloscope is mainly used to display the voltage waveforms of input and output signals in the control system, for maintenance personnel to analyze and judge faults in the electronic control system based on the waveforms. The oscilloscope has a faster display speed than general electronic devices and is the only detection instrument that can display instantaneous waveforms. It is an important equipment in fault diagnosis of electronic control systems.

6. Simulation method

The simulation method is used to simulate the input signal of a car computer using a sensor simulation tester when the sensor is disconnected and other lines are connected normally, replacing the sensor's operation. Based on the disappearance or existence of the fault phenomenon, the method is used to determine the quality of the sensor.

7. Alternative method

The replacement method is a method of testing and replacing suspicious sensors to find faults, also known as the replacement method. The substitution method can determine the location of the fault or narrow down the scope of the fault, but it may not necessarily determine the cause of the fault. When repairing sensors, it is best to use sensors of the same model, year, model, and specification to temporarily replace the sensors in question.

In summary, measuring the quality of sensors requires the use of multiple testing methods to ensure their accuracy and reliability. If the sensor malfunctions or is damaged, timely replacement or repair is necessary to avoid any impact on the system and potential safety hazards.