Best volatile organic compounds sensor
Temperature and humidity are closely related to people’s daily life and agricultural production. Therefore, the Temperature and humidity sensor in agriculture, which is dedicated to measuring and recording temperature and humidity, has very important applications in various industries. The sensor measures the temperature and humidity through a professional detection device, and then converts it into an electrical signal or other required form of information output according to a certain rule, so that the user can intuitively obtain the temperature and humidity. In agricultural production management, the Temperature and humidity sensor in agriculture mainly has the following two typical applications.
What are VOC?
First, understanding the characteristics of VOCs is critical to understanding how sensors work. VOC refers to a kind of volatile organic compounds, which are widely found in indoor and outdoor environments and can originate from vehicle exhaust, human breath, homes, paints, wallpapers, etc. High indoor VOC concentrations can cause discomfort to the human body and may cause health problems over time.
The working principle of Volatile organic compounds sensor
The basic principle of the VOC gas sensor is the principle of chemical adsorption and reaction, that is, the purpose of detecting the concentration is achieved after the compound is adsorbed by a special chemical material. The sensor is mainly composed of two parts: detection element and signal processing circuit.
In terms of detection components, Electrochemical gas sensor, Semiconductor gas sensor and Infrared gas sensor are commonly used. Among them, the principle of the infrared sensor is to use the infrared absorption spectrum generated by VOC at a specific wavelength for detection. It can detect a variety of VOC molecules and has good accuracy and stability.
In addition, there are semiconductor sensors based on gas-sensitive materials, which can indicate VOC concentration by detecting molecules adsorbed on the surface of the sensor and measuring changes in their electrical properties.
Electrochemical sensors are based on the principle of electrochemical reactions, using the redox process of the detected compound to measure its concentration
In terms of signal processing circuits, a differential measurement circuit is usually used. Its working principle is that as the concentration of the detected substance changes, the signals on the two electrode series will also differ, thereby measuring the potential difference and converting it into a current signal or voltage. Signal. These signals will be sent to devices such as amplifiers and analog-to-digital converters to generate digital signals, which will be sequentially entered into single-chip microcomputers or computers for data processing, analysis and output.
In short, the voc air quality sensor is mainly based on the principle of chemical reaction, and the difference of the detection element leads to the difference of the adsorbed substances, so as to realize the detection of the VOC concentration. At the same time, the design of the sensor is also very important. A reasonable signal processing circuit can greatly improve the accuracy and stability of the sensor, enabling it to detect the VOC concentration more accurately.