The wireless temp humidity sensors are devices or devices that can convert temperature and humidity into electrical signals that can be easily measured and processed. Because temperature and humidity are closely related both in physical quantity itself and in real life, temperature and humidity integrated sensors will be generated accordingly. The wireless temp humidity sensors on the market generally measure temperature and relative humidity.
1.1 Concepts of Temperature and Humidity
Because temperature and humidity are closely related from both physical quantity and real life, temperature and humidity integrated sensors will be generated accordingly. Temperature and humidity sensors are devices or devices that can convert temperature and humidity into electrical signals that can be easily measured and processed. The wireless temp humidity sensor on the market generally measure temperature and relative humidity.
Temperature: Measuring the physical quantity of the object's heat and cold is one of the seven basic physical quantities in the international system of units. In production and scientific research, many physical phenomena and chemical processes are carried out at a certain temperature, and people's lives are closely related to him.
Humidity: Humidity has been closely related to life for a long time, but it is difficult to express it in terms of quantity.
Some definitions of humidity:
Absolute humidity: It refers to the actual amount of water vapor in the air per unit volume, generally in grams. Temperature has a direct impact on absolute humidity. Generally, the higher the temperature, the more water vapor, the greater the absolute humidity; on the contrary, the smaller the absolute humidity.
Saturated humidity: The maximum amount of water vapor that can be accommodated in the air per unit volume at a given temperature. If this limit is exceeded, the excess water vapor will condense and become water droplets, at which time the air humidity becomes known as saturated humidity. The saturated humidity of air is not constant; it varies with temperature. The higher the temperature, the more water vapor can be contained in the unit volume of air, and the greater the saturated humidity.
Dew Point: It refers to the air containing a certain amount of water vapor (absolute humidity). When the temperature drops to a certain extent, the water vapor will reach saturated state (saturated humidity) and begin to liquefy into water. This phenomenon is called condensation. The temperature at which water vapor begins to liquefy into water is called dew point temperature. If the temperature continues to drop below the dew point, supersaturated water vapor in the air will condense into droplets on the surface of the object. In addition, wind is closely related to air temperature and humidity, and it is also one of the important factors affecting air temperature and humidity changes.
1.2 Measurement of Temperature and Humidity
Humidity measurement technology has a long history. With the development of electronic technology, modern measurement technology has also developed rapidly. Humidity measurement can be divided into two or thirty kinds in principle. The expression of humidity includes absolute humidity, relative humidity, dew point, the ratio of humidity to dry gas (weight or volume), etc. But humidity measurement is always one of the most famous problems in the field of measurement in the world. A seemingly simple value involves a rather complex physical-chemical theoretical analysis and calculation. Initial participants may neglect many factors that must be paid attention to in humidity measurement, thus affecting the rational use.
Common humidity measurement methods include dynamic method (double pressure method, double temperature method, shunt method), static method (saturated salt method, sulfuric acid method), dew point method, wet-dry sphere method and various electronic sensor method.