Standards of the measurement principle and development trends of infrared thermometers
There are many advantages to using an infrared thermometer for non-contact temperature measurement, and its applications range from small or hard-to-reach objects to corrosive chemicals and sensitive surfaces. This article will discuss this advantage, give the decisiveness of choosing the right infrared thermometer, and explain the scope of application. Due to the movement of atoms and molecules, every object radiates electromagnetic waves. The most important wavelength or spectral range for non-contact temperature measurement is 0.2 to 2.0 μm. Natural rays in this range are called thermal radiation or infrared rays.
Test instruments that measure the temperature of infrared rays radiated by the object to be measured are called radiation thermometers, radiation thermometers or infrared thermometers according to the German industrial standard DIN16160. These names also apply to those instruments that measure temperature by visible colored rays radiated by the object being measured, and that derive the temperature from the radiation density of the relative spectrum.
1. Advantages of infrared thermometer temperature measurement
Non-contact temperature measurement by receiving infrared rays radiated by the object under test has many advantages. In this way, the temperature of objects that are difficult to reach or are in motion can be measured without any problem, such as materials with poor heat transfer properties or very small heat capacity. The short response time of the infrared thermometer enables effective regulation loops to be quickly implemented. Thermometers have no parts that wear out, so there are no ongoing costs associated with using a thermometer. Especially for very small objects to be measured, such as contact measurement, a large measurement error will occur due to the thermal conductivity of the object. Thermometers can be used without any problems here, and are used with corrosive chemicals or sensitive surfaces, such as paint, paper and plastic rails. Through long-distance remote control measurement, it can be far away from the dangerous area, so that the operator is not in danger.
2. Development Trend
Like many fields of sensing technology, the development trend of thermometers is also towards small, exquisite shapes. The round housing with central thread is the most ideal shape for installation in machines and equipment. This development trend is This is achieved through continuous miniaturization of electrical components and a high degree of calculus, which makes smaller and more sophisticated electrical components concentrated in smaller and smaller spaces. Compared with past analog technology, the application of microcontrollers improves the precision of the linearization height of the detector signal, thereby also improving the accuracy of the instrument.
The market supply requires fast and cheap measurement value reception, which can directly output a temperature-proportional, linear current/voltage signal. Measurement value processing, such as flattening function, special value storage, or boundary contact will be placed in the intelligent On the display, regulator or SPS (Program Controller), the emissivity can be adjusted through an external cable. It can be corrected outside the danger zone even if the machine is running. At this time, it can also be adjusted by the SPS. Through the use of body controls, the data bus interface can now be realized without any problems, but the network connection has not yet been realized, and the continued processing of signals still uses the standard analog signals of the past. In the detector section, new materials were used as photoelectric sensors, which confirmed the improvement in sensitivity and even resolution. Among hot film sensors, new sensors only require shorter adjustment times. The latest development of thermometers with sights is the replacement lens with zoom, which can be replaced without calibration recheck, using the same basis for different measurement positions. Instruments, saving warehouse management costs.
