【 Weak current College 】 infrared thermometer technical, infrared thermometers are used---Power By 【 China power house network 】

Infrared temperature measuring device works and application (1)
Summary: this article is a combination of domestic and international development of infrared technology and applications, Jane Shao-the basic theory of infrared technology, described the infrared camera works, development and classification. 1. Overview of infrared measurement technology in the production process, product quality control and monitoring equipment online troubleshooting and security protection and saving energy has played an important role. In the last 20 years, non-contact infrared thermometer is technically is the rapid development, the performance is constantly improving, growing variety features are increasing all the time, the scope is also continually expanding market share year on year growth. Compared to contact temperature measurement, infrared temperature measurement with fast response times, contactless, use safety and long life and other advantages. Non-contact infrared thermometer including portable, on-line and scan-three series, and equipped with various options and computer software, and each series and the various models and specifications. In different specifications of various types of thermometer, proper selection of infrared thermometer model to the user, is very important.
Infrared technology is the ninth country--key promoting project license on technology, infrared detection is an on-line monitoring (without interruption)-high-tech detection technology that sets imaging technology, computer technology, image processing technology, by receiving objects emit infrared (IR), the thermal image displayed on the screen to determine accurately the object surface temperature distribution with accurate, real-time, fast, etc. Any object as its own elements of movement, and radiates infrared heat energy to the surface forming a certain temperature, commonly known as "thermography". Infrared absorption of diagnostic techniques it is through this infrared radiation energy, detect device surface temperature and temperature field of distribution, thus determining device heating. The current application's Red Waizhen technology test equipment, such as infrared pyrometer, infrared TV, infrared, etc. Like infrared TV, infrared camera and other equipment using thermal imaging technology will see "thermography" into a visible image, the test results in an intuitive, high sensitivity, which can detect the device minor thermal state change that accurately reflects the internal and external heating, high reliability and potential for discovery of devices are very effective.
Infrared diagnosis technique on the early failure of electrical equipment and insulation performance to make reliable forecasts, the traditional electrical equipment preventive test maintenance (prevention trial is 50 's introduction of the former Soviet Union standards) to predict the State maintenance, this is the modern power enterprise development direction. Especially now, ultra high voltage large unit for the reliable operation of power systems, power grid stability, put increasingly higher demands. With the continued development of modern science and technology become increasingly mature and perfect, the use of infrared condition monitoring and Diagnostics technology with distance, no contacts, no samples, no disintegration, and accurate, fast, intuitive, real-time online monitoring and diagnostics of electrical equipment most failures (almost cover all electric equipment in various fault detection). It attracted the attention of the electric power industry at home and abroad (foreign late 1970s universal application of an advanced condition-based maintenance system), and rapid development. Infrared technology, to improve the reliability of the electrical equipment, improve operational effectiveness and economic efficiency, reduce maintenance costs are very important. Is currently in the field of predictive maintenance generally promoted a very good tool, but also make maintenance and equipment of health level to a higher level.
Using infrared imaging technology to running equipment for non-contact detection, its temperature field distribution measurement of any part of, the temperature value, the various external and internal fault diagnostics, with real-time, telemetry, intuitive and quantitative measurement, etc., used to detect power plants, substations and transmission lines running equipment and electrical equipment is very easy, and effective.
Use of thermal imager testing online electrical equipment by infrared thermography method. Infrared thermography method is the industry used to nondestructive detection, detection equipment performance and control their running state of a new technology. With the traditional temperature measurement (e.g. thermocouple, different melting point of wax tablets, placed in the measured surface or body) compared to thermal imager can be within a certain distance in real time, quantitative, online testing, the temperature of the hot spots, by scanning, you can also draw a device running temperature gradient thermography, and high sensitivity, are not affected by electromagnetic interference, easy to use site. It can be-20 ° c to 2000 ° c within the wide-range to 0.05 ℃ high resolution detection of electrical equipment for heat-induced failure revealed as conductor connectors or clamp fever, as well as electrical equipment too hot in the local and so on.
Electrical equipment diagnosis of infrared technology is a new subject. It is the use of thermal effects induced by electric equipment, using special equipment gets sent from the device surface infrared radiation information, which in turn determine the device status and the nature of a defect in synthesis technology. 2. infrared theory of 1672, it was discovered that the Sun (white light) is composed of various colors of light, at the same time, the Newton made a monochromatic light in nature than white light simpler famous conclusion. Use beamsplitter put sunlight (white) into red, Orange, yellow, green, green, blue, purple, and other assorted monochromatic light. 1800, United Kingdom physicist F. W. j. Xu from hot to study various shade, the discovery of infrared. He studies various shade of heat, intentionally put a unique window of anechoic chamber with dark plate is blocked, and the Board had a rectangular hole, the hole of a beamsplitter. When the sunlight through a Prism, it is broken down as colored light, and use a thermometer to measure the patches of different colors in the heat. In order to compare with the ambient temperature, Xu, used in the color patches of several branch near as compared with a thermometer to measure ambient temperature. Test, he came across a strange phenomenon: in patches of red light, a thermometer, other than the indoor temperature high of numerical instructions. After repeated testing, this so-called heat up in the high temperature area, always located on the edge of light most of red light. He announced that solar radiation in the visible light line, a human eye's "hotline", this invisible "hotLine "is located in the red light outside, called infrared. Infrared is a kind of electromagnetic and radio frequency and the nature of visible light, infrared light, like the discovery of human understanding of the nature of a leap, to study, use and development of infrared technology opened up a whole new broad road.
Infrared wavelength in 0.76 ~ 100 μ m, according to the wavelength range can be divided into near-infrared, infrared, far infrared, infrared four categories, it is in the continuous spectrum of electromagnetic waves in position is in radio waves and the area between the visible light. Infrared radiation is one of nature's most extensive electromagnetic wave radiation, it is based on any objects in the General environment will produce their own molecular and Atomic motion without rules, and keep the thermal infrared radiation energy, molecular and Atomic motion more violent, more radiant energy, on the contrary, the smaller the radiation energy.
Temperature at absolute zero or more objects, because of their molecular motion and infra-red radiation. Through infrared detector will object radiation power signal conversion to electrical signals, the imaging device output signal can fully mimic scan objects correspond one-to-one with a surface temperature of space distribution, electronic systems, to display, and surface heat distribution corresponding thermography. 　　Use this method to achieve the target distance hot image imaging and measurement and analysis. 2.1 thermal imager principle thermal infrared imager is the use of infrared detectors, optical imaging lens and optical-scan systems (now state-of-the-art technology will eliminate the focal plane of light mechanical scanning system) accept the test objectives of infrared radiation energy distribution graph reflects infrared detector of photosensitive element, in optics and infrared detector, there is a light machine scanning mechanism (focal plane thermal imager in the absence of such bodies) to be logging objects of infrared thermal image is scanned, and focused on the unit or UV detector, the probe will infrared radiant energy is converted into electrical signals, with the enlargement process, transform, or of standard video signal through the TV screen or monitor displays infrared thermography. This kind of thermography and surface heat distribution field corresponds essentially to be logging target object sections of infrared thermal image map because the signal is very weak, compared with the visible image, the absence of hierarchy and three-dimensional sense, therefore, the actual action process to better judge the test objectives of infrared heat distribution in the field, often using some complementary measures to increase the instruments of practical functions, such as image brightness, contrast control, calibration, pseudo color paint technology 2.2 thermal imager of 1800, United Kingdom physicist F. W. j. Xu, discovered infrared, opened up the human application of infrared technology's broad road. In the second world war, Germany with infrared variable like tube as opto-electrical converter, developed active night vision and infrared communication equipment, infrared technology development laid the Foundation.
After the second world war, first by the United States de Saram instrument company after nearly a year of exploration, development and research for first-generation military area of infrared imaging system, called infrared homing vision systems (FLIR), it is the use of optical and mechanical system under test objectives of infrared scanning. By photon detector receive two dimensional signs of infrared radiation by a series of photoelectric conversion and processing equipment, the formation of video image signals. This system, the original forms is a non-immediate automatic temperature recorder, then with the 1950s Indium antimonide and germanium doped mercury photon detector development, began to appear high speed scanning and real-time display of the target system of thermal images.
In the early 1960s, Sweden AGA developed second-generation infrared imaging device, it is in the infrared homing on the basis of the Visual system to increase the temperature of the feature, called thermal infrared imager.
Start due to confidentiality reasons, in the developed countries are also limited to military, applied thermal imaging device that night or thick curtain cloud detection in each other's goals, objectives and detect camouflage high-speed movement of the target. Thanks to the support of national funds, investment research and development costs, equipment costs are high. After taking into account the development of industrial production, combined with the practicality of industrial infrared detection feature, take compression equipment cost. Lower production costs and according to the civil requirements by reducing the scanning speed to improve image resolution, the progressive development of the civil sphere.
The mid-1960s, AGA company developed the first set of real-time imaging system for industrial use (THV), the system consists of liquid nitrogen cooling, 110V power voltage supply, weighs approximately 35 kg, the use of portability is very poor, thanks to the improvement of several generations of equipment, development of 1986 infrared camera has no need of liquid or gas, but the way in thermoelectric cooling, the available battery power supply; 1988 launched fully functional thermal imager, temperature measurement, modify, analysis, image acquisition, storage, fitness, weight less than 7 kg, instrument functionality, accuracy and reliability are significantly improved.
By the mid-1990s, the United States FSI companies successfully developed first by military technology (FPA) conversion and commercialization of new infrared camera (CCD) is a focal plane array structure of a cementitious imaging device, more advanced technical capabilities, spot temperature measurement is only targeted exposure of the image, and the information stored in the computer's PC card, that is, the completion of all operations, various parameters set to go back to modified interior with software and analyze the data, the final inspection report obtained directly, due to technical improvements and changes in the structure, replacing the complex mechanical scanning, instrument weight has less than 2 kg, use as a handheld video camera, can be easily operated with one hand.
Today, infrared thermal imaging system has been in power, fire control, chemical and medical, and other areas has been widely used. 　　Infrared camera in the world economy is playing an important role. 2.3 thermal imager classification infrared spectrophotometry machine Scanning Imaging general system and non-scan Imaging System. Light machine scanning imaging system uses the unit or plural (element number 8, 10, 16, 23, 48, 55, 60, 120, 180 or even more) photoconductive or photovoltaic infrared detectors, use detector is slow, mainly frames site response to lack of timeFast, multiple array probes can be made into high-speed real-time thermal imager. Non-scan imaging of thermal imager, such as the recent launch of array staring imaging of focal plane thermal imager is a new generation of thermal imaging device performance is much better than light machine scanning imager, gradually replacing light machine scanning imager trend. Its key technology is the detector from monolithic integrated circuit, the measured goal of the entire field of vision is focused on it, and the image clearer, easier to use, the instrument is compact, with auto-focus image freeze, continuous zoom, point temperature, such as temperature, moderate line voice comment images, and other functions, the instruments used PC card storage capacity up to 500 images.
Infrared TV is the infrared camera. Infrared TV through the Pyroelectric camera tube (PEV) accept the measured object's surface infrared radiation, and to target the distribution of heat radiation in the invisible thermal images into video, thus, Pyroelectric camera tube is infrared light key device TV, it is a real-time imaging, wide spectral Imaging (3 ~ 5 μ m and 8 ~ 14 μ m better frequency response) with a medium resolution of thermal imaging devices, mainly by the lens, target surface and the electron gun made up of three parts. Its technical features are to be logging target line of infrared radiation Imaging through the lens to the Pyroelectric camera tube, used at normal temperature hot TV detector and electron beam scanning and target surface imaging technology. Thermal imager of main parameters are: 2.3.1 working band; work in-band refers to thermal infrared imager in the infrared detector response wavelength region, usually 3 to 5 μ m or 8 ~ 12 μ m.
2.3.2 detector types; detector type refers to the use of an infrared device. Is the unit or plural (element number 8, 10, 16, 23, 48, 55, 60, 120, 180, etc.) photoconductive or photovoltaic infrared detector, which uses the element has lead sulfide (PbS), lead selenide (PnSe) and TE insb (InSb), Mercury cadmium telluride (HgCdTe), tellurium, Tin, lead (PbSnTe), germanium doped (Ge: X) and Silicon-doped (Si: X), etc.
2.3.3 scan systems; General for our standard SECAM, PAL.
2.3.4 display; refers to the screen is black and white display or pseudo color display.
2.3.5 temperature measurement range; means for the determination of the minimum temperature and the maximum limit of the temperature range of values.
2.3.6 temperature measurement accuracy; infrared temperature of maximum and instrument range of percentages.
2.3.7 maximum working hours; infrared imaging system allows continuous working hours.