Basic Concepts of Temperature Measurement
Temperature is a physical quantity that measures how hot or cold an object is. It plays an extremely important role in production and scientific experiments. It is one of the seven basic physical quantities in the International System of Units (SI). From the point of view of energy, temperature is a physical quantity that describes the distribution of energy among different degrees of freedom of the system; from the point of view of heat balance, temperature is a physical quantity that describes the degree of coldness and heat of a heat balance system; from a microscopic point of view, temperature marks the irregularity of molecules inside the system The intensity of the movement, the object with high temperature, the average kinetic energy of molecules is large, and the object with low temperature, the average kinetic energy of molecules is small.
In the early days, people started from the sense of human organs, and distinguished the temperature according to the degree of cold or heat they felt or touched. The results obtained in this way are often unreliable and inaccurate. Studies have shown that the properties of almost all substances are related to temperature, such as size, volume, density, hardness, elastic transverse volume, destructive strength, electrical conductivity, magnetic permeability, light radiation intensity, etc., using these properties and their changes with temperature Temperature measurement is possible. That is to say, temperature can only be measured indirectly through certain characteristics of objects that change with temperature, and the scale used to measure the temperature value of objects is called a temperature scale. It specifies the reading starting point (zero point) of temperature and the basic unit of measuring temperature. At present, the most commonly used temperature scales in the world are Fahrenheit temperature scale, Celsius temperature scale, thermodynamic temperature scale and international practical temperature scale.
Proper Use of Handheld Infrared Thermometer
1 ambient temperature. If the infrared thermometer is suddenly exposed to an ambient temperature difference of 20°C or higher, allow the instrument to adjust to the new ambient temperature within 20 minutes.
2. Only measure the surface temperature of the object. Infrared thermometers cannot measure the internal temperature of objects
3. Pay attention to environmental conditions. Steam, dust, smoke, etc. will block the optical system of the instrument and affect the temperature measurement.
4. Locate hotspots. To find a hot spot, first use the instrument to aim at the target, and then scan up and down on the target until the hot spot is identified.
5. Hand-held infrared thermometers cannot measure temperature through glass. Glass has very specific reflective and transmissive properties that prevent temperature readings, but allow temperature measurements through the infrared window. Infrared thermometers are best not used for temperature measurement on bright or polished metal surfaces (stainless steel, aluminum, etc.).
