How to choose a good sensor

Optički senzor temperature, Inteligentni sistem nadzora, Distribuirani proizvođač optičkih vlakana u Kini

There are many types of sensors, including commonly used thermal resistance sensors, fiber optic sensors, itd. FJINNO has independently developed fiber optic temperature sensors. Welcome to contact us.

The characteristics of sensors include:

1. Linear range

The linear range of a sensor refers to the range where the output is proportional to the input. In theory, within this range, sensitivity remains constant. The wider the linear range of the sensor, the larger its range and can ensure a certain measurement accuracy. When selecting a sensor, once the type of sensor is determined, the first thing to consider is whether its range meets the requirements. Međutim, in reality, 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 nonlinear errors can be approximated as linear, which will bring great convenience to the measurement.

2. Stability

The ability of a sensor to maintain its performance unchanged after a period of use is called stability. The factors that affect the long-term stability of sensors, in addition to the structure of the sensor itself, are mainly the environment in which the sensor is used. Stoga, in order for sensors to have good stability, they must have strong environmental adaptability.

3. Sensitivity selection

Usually, within the linear range of a sensor, 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 beneficial for signal processing. Međutim, it should be noted that the sensitivity of the sensor is high, and external noise unrelated to the measurement is also easily mixed in, which can be amplified by the amplification system and affect the measurement accuracy. Stoga, it is required that the sensor itself should have a high signal-to-noise ratio and minimize the introduction of interference signals from the outside world.

The sensitivity of sensors is directional. When the measured quantity is unidirectional and requires high directionality, sensors with low sensitivity in other directions should be selected; If the measured vector is a multidimensional vector, the smaller the cross sensitivity of the sensor, the better.

Determine the type of sensor based on the measurement object and measurement environment

To carry out a specific measurement work, the first thing to consider is what principle of sensor to use, which requires analyzing various factors before determining. Because even when measuring the same physical quantity, there are multiple principles of sensors to choose from. Which principle of sensor is more suitable needs to consider the following specific issues based on the characteristics of the measured quantity and the usage conditions of the sensor: the size of the range; The requirement of the measured position on the volume of the sensor; Is the measurement method contact or non-contact; Signal extraction method, wired or non-contact measurement; The source of the sensor, whether it is domestically produced or imported, whether the price is affordable, or self-developed.

After considering the above issues, we can determine which type of sensor to choose, and then consider the specific performance indicators of the sensor.

Frequency response characteristics

The frequency response characteristics of sensors determine the frequency range to be measured, and must maintain undistorted measurement conditions within the allowable frequency range. In fact, the response of sensors always has a certain delay, and it is hoped that the shorter the delay time, the better. The frequency response of sensors is high, resulting in a wide range of measurable signal frequencies. Međutim, due to the influence of structural characteristics, the inertia of mechanical systems is large, and sensors with low frequencies can measure signals with lower frequencies.