Today, Wuxi Rihuan Sensor Technology Co., Ltd. will introduce to you the core guide for sensor selection and a comprehensive analysis of common issues. 

In the current era of rapid development in industrial automation, the Internet of Things, and intelligent devices, sensors, as the "window for perceiving the world", have become indispensable core components in various intelligent systems. From quality control in industrial production lines, environmental monitoring in smart homes, to obstacle detection in self-driving cars, the precise operation of sensors directly determines the operational efficiency and reliability of the systems. However, issues such as the principles and characteristics of sensors, selection logic, and practical applications often confuse beginners. This article will systematically explain the key points of sensor technology through question-and-answer format, helping users master the correct usage methods and avoid common misunderstandings. 

I. Basic Understanding: Definition and Working Principle of Sensors

Question: What is a sensor? What is its basic working principle? Answer: A sensor is a device that can sense a specified measured quantity and convert it into an available output signal according to a specific rule. The core working principle can be summarized as two steps: Firstly, through the sensitive element, changes in the measured physical quantity (such as temperature, pressure, light intensity, humidity, displacement, etc.) are captured. Then, with the aid of the conversion element, these physical quantity signals are converted into electrical signals or other forms that are convenient for transmission and processing, ultimately achieving precise perception of the measured object.

II. Key to Selection: How to Choose the Appropriate Sensor?

Question: When faced with numerous types of sensors, how should one select a product that meets one's own needs? Answer: Sensor selection requires comprehensive consideration of multiple factors to ensure a high degree of compatibility with the actual application scenario. Specific factors include:

Clearly define the measurement object and core requirements, and determine the type of physical quantity to be monitored;

Identify the specific application environment and requirements;

Evaluate the performance and compatibility of different sensors with the application scenario;

Consider the cost and reliability of the sensor;

Select the sensor based on the above considerations. 

Define the required measurement range and accuracy level to avoid any impact on the measurement results due to mismatched parameters; 

Assess the conditions of the working environment, such as temperature, humidity, air pressure, and whether there is vibration or electromagnetic interference, etc. 

Ensure that the output signal type of the sensor (such as analog signal or digital signal) is compatible with the subsequent processing system; 

Taking into account the limitations of the installation space and the feasibility of the installation method, avoid any impact on usage due to installation issues. 

Balance the cost budget with the requirements for later maintenance, and select the most cost-effective solution. 

III. Common Faults: Analysis of the Causes of Unstable Signal Output

Question: What could be the reasons for unstable signal output when the sensor is in use? Answer: Abnormal fluctuations in signal output are usually related to the following factors:

Power supply issues, such as fluctuating power supply voltage and insufficient power supply capacity, causing the sensor to fail to work stably; 

External environmental disturbances, such as electromagnetic interference, mechanical vibration, and temperature fluctuations, affect signal transmission and perception accuracy; 

The aging or damage of the sensor itself, as well as the degradation of the performance of the sensitive components, will directly lead to signal distortion. 

Faults in the connection lines, such as loose wiring or poor contact, can cause interruption or instability in signal transmission; 

The environmental conditions exceeded the rated working range of the sensor, causing it to be unable to properly sense the measured physical quantity. 

Inspection suggestions: Prioritize checking the stability of the power supply, then investigate external environmental interference factors, and finally conduct tests on the sensor itself and its connection lines.

IV. Precision improvement: How to reduce sensor measurement errors?

Question: In practical applications, what methods can effectively reduce the measurement errors of sensors? Answer: To improve measurement accuracy, the following measures can be taken:

Regularly calibrate the sensor and promptly correct performance deviations; 

Optimize the installation location and method to avoid signal interference caused by improper installation; 

Take compensatory measures for complex environments, such as temperature compensation and humidity compensation, etc. 

Combined with the signal conditioning circuit, it performs filtering, amplification and other processing on the original signal to improve the signal quality. 

By using the digital filtering algorithm, the interference noise in the signal is further eliminated. 

Ensure that the sensor always operates within its optimal range and in accordance with environmental parameters, and avoid any degradation in accuracy under extreme conditions. 

V. Calibration Points: Why do sensors need to be calibrated regularly?

Question: Why do sensors need to be calibrated regularly? How should the calibration cycle be determined? Answer: Regular calibration is crucial for ensuring the measurement accuracy of sensors. The main reasons include:

The internal components of the sensor will age over time, causing the performance parameters to drift; 

Long-term influences such as environmental temperature and humidity can alter the sensing characteristics of the sensor. 

Mechanical stress generated during transportation, installation or use may cause slight deformation of the sensitive components, thereby affecting the measurement accuracy. 

Meet the traceability requirements of the measurement results and ensure that the data is reliable and comparable. 

The determination of the calibration cycle should be based on the actual usage situation: According to the usage frequency of the sensor, the severity of the working environment, and the requirements for measurement accuracy, the calibration interval should be reasonably set. Generally, it is recommended to shorten the calibration cycle in key application scenarios.

VI. Range Selection: How to determine the appropriate sensor range?

Question: What principles should be followed when selecting the sensor range? Answer: Range selection should take into account both practicality and accuracy. The core principles include:

Fully cover the normal fluctuation range of the measured parameters to ensure that the daily measurement data is within the range of the sensor; 

Reserve 10% - 20% of overload margin to cope with peak parameter values in emergency situations, and to prevent the sensors from being damaged due to overload. 

Taking into account the maximum values of the measured parameters under extreme conditions, it is ensured that the sensor can still function properly in special circumstances. 

Pay attention to the correlation between the measurement range and accuracy: Generally speaking, the larger the measurement range of a sensor, the lower its measurement accuracy will be. A balance needs to be struck between the two. 

Best practice: Keep the measured value within the 60%-80% range of the sensor's measurement range. This ensures measurement accuracy while effectively avoiding the risk of overload. 

Current sensor technology is evolving rapidly and its application scenarios are becoming increasingly widespread. During actual use, various technical problems are inevitable. We hope that the summary and analysis in this article can provide valuable references for relevant practitioners, helping them avoid detours in project selection and technical decision-making, and fully exert the core perception function of sensors. If you want to find more adaptable and reliable sensor products, you might as well pay attention to Rihuan Sensing - as a high-tech enterprise deeply engaged in sensing technology, Rihuan Sensing not only has a complete product line covering proximity sensors, photoelectric sensors, safety gratings, etc., but also can provide customized solutions to meet different scene requirements. From stable operation under harsh conditions to high-precision precise measurement, Rihuan Sensing always takes "Quality is the life of the enterprise" as its core value, and with high-performance and cost-effective products and wholehearted service, it has become the trusted choice for many enterprises in sensor selection.