Firstly, the type of sensor should be determined according to the difference between the measured object and the measured environment.
Before the specific measurement, we should first consider what kind of sensors should be used for combustible gas detectors, and we need to comprehensively consider various factors before determining. Because, even when measuring the same physical quantity, there are many kinds of sensors to choose from, and which principle sensor is more suitable needs to be considered according to the measured characteristics and the use conditions of the sensor. It is suggested that the following specific problems should be considered in industrial mining network: the size of measurement range; Requirements of the measured position on the sensor volume; Whether the measurement method is contact or non-contact; Signal extraction method, wired or non-contact measurement; The source of the sensor is domestic or imported, and the price is affordable or self-developed. After considering the above problems, we can determine which type of sensor to choose, and then consider the specific performance indicators of the sensor.
Secondly, the choice of sensor sensitivity is also very important.
Generally speaking, within the linear range of the sensor, the higher the sensor sensitivity of the toxic gas detector, 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 beneficial to signal processing. However, Cangzhou Guhai safety protection experts remind you that the sensitivity of the sensor is high, and external noise unrelated to the measurement is easy to be mixed in, and it will be amplified by the amplification system, which will affect the measurement accuracy. Therefore, the sensor itself is required to have a high signal-to-noise ratio and try to reduce the interference signals introduced by the outside world. The sensitivity of the sensor is directional. When the measurement is unidirectional and requires high directivity, sensors with low sensitivity in other directions should be selected; If the measured vector is a multi-dimensional vector, the smaller the cross sensitivity of the sensor, the better.
Thirdly, the frequency response characteristics of the sensor should be considered.
The frequency response characteristics of the sensor determine the frequency range to be measured, and the measurement conditions must remain undistorted within the allowable frequency range. In fact, there is always a certain delay in the response of the sensor, and it is hoped that the shorter the delay time, the better. The higher the frequency response of the sensor, the wider the frequency range of the measurable signal. However, due to the influence of structural characteristics, the inertia of mechanical system is large, and the frequency of measurable signal is low because of the low frequency of sensor. In dynamic measurement, the response characteristics should be based on the characteristics of the signal (steady state, transient state, random, etc.). ) to avoid too many mistakes.
Finally, the linear range of the sensor is also an important link that we need to consider.
The linear range of the sensor refers to the range in which the output is proportional to the input. Theoretically, within this range, the sensitivity remains unchanged. The wider the linear range of the sensor is, the larger its range will be, and a certain measurement accuracy can be guaranteed. When selecting a sensor, after determining the type of the sensor, we should first look at whether its range meets the requirements. But in fact, no sensor can guarantee absolute linearity, and its linearity is relative. When the required measurement accuracy is low, in a certain range, the sensor with small nonlinear error can be approximately regarded as linear, which will bring great convenience to the measurement.
How to choose a better combustible gas sensor? I suggest that you choose the most effective sensor by considering the four factors: measuring object and measuring environment, sensitivity, frequency response characteristics and linear range.