What is the principle of sensor type selection?
How should we choose sensor types and principles in our work?
1.Selection based on sensitivity
Generally, in the linear range of the sensor, it is desirable that the higher the sensitivity of the sensor, the better. Because only when the sensitivity is high, the value of the output signal corresponding to the measured change is relatively large, which is conducive to signal processing. However, it should be noted that the sensitivity of the sensor is high, and external noise that is not related to the measurement is also easily mixed in, and it is also amplified by the amplification system, which affects the measurement accuracy. Therefore, the sensor itself is required to have a high signal-to-noise ratio to minimize interference signals introduced from the outside. The sensitivity of the sensor is directional. When the measured is a single vector, and its directivity requirements are high, you should choose a sensor with low sensitivity in other directions; if the measured is a multi-dimensional vector, the smaller the cross-sensitivity of the sensor, the better.
2.According to the stability of the sensor
The ability of a sensor to maintain its performance after a period of time is called stability. In addition to the structure of the sensor itself, the factors affecting the long-term stability of the sensor are mainly the environment in which the sensor is used. Therefore, to make the sensor have good stability, the sensor must have strong environmental adaptability. Before selecting a sensor, it should investigate its use environment, and choose the appropriate sensor according to the specific use environment, or take appropriate measures to reduce the environmental impact.
3. Judging the frequency response characteristics
The frequency response characteristic of the sensor determines the frequency range to be measured, and it must remain undistorted within the allowable frequency range. In fact, there is always a certain delay in the response of the sensor. It is hoped that the shorter the delay time, the better. The higher the frequency response of the sensor, the wider the range of measurable signal frequencies. In dynamic measurement, the response characteristics of the signal (stable, transient, random, etc.) should be used to avoid excessive errors.
4.According to the linear range of the sensor
The linear range of the sensor is the range where the output is proportional to the input. In theory, within this range, the sensitivity remains constant. The wider the linear range of the sensor, the larger its range, and it can guarantee a certain measurement accuracy. When selecting a sensor, when the type of sensor is determined, first of all, it depends on whether its range meets the requirements. But in fact, no sensor can guarantee absolute linearity, and its linearity is also relative. When the required measurement accuracy is relatively low, within a certain range, sensors with small non-linear errors can be approximated as linear, which will bring great convenience to the measurement.
5. Determine the type according to the measurement object and measurement environment
To carry out a specific measurement, we must first consider what kind of sensor to use. This requires analysis of many factors before it can be determined. Because, even when measuring the same physical quantity, there are multiple principles of sensors to choose from, which one is more suitable, you need to consider the following specific issues according to the characteristics of the measurement and the conditions of use of the sensor: the size of the range; Requirement of the measured position on the volume of the sensor; the measurement method is contact or non-contact; the method of signal extraction, wired or non-contact measurement; the sensor, domestic or imported, whether the price can be afforded, or developed by ourselves. After considering the above issues, we can determine what type of sensor to choose, and then consider the specific performance indicators of the sensor.
6, the accuracy of the sensor can not be ignored
Accuracy is an important performance indicator of the sensor, and it is an important link related to the measurement accuracy of the entire measurement system. The higher the accuracy of the sensor, the more expensive it is. Therefore, as long as the accuracy of the sensor meets the accuracy requirements of the entire measurement system, it does not have to be selected too high. In this way, you can choose the cheaper and simpler sensor of Atlas air compressor among many sensors that meet the same measurement purpose. If the measurement purpose is qualitative analysis, a sensor with high repetition accuracy can be used, and it is not suitable to use a high absolute value accuracy. If it is for quantitative analysis, accurate measurement values must be obtained, and a sensor with an accuracy level that can meet the requirements is required.
If you want to know more, our website has product specifications for sensor， you can go to ALLICDATA ELECTRONICS LIMITED to get more information