Sunday, March 27, 2011
【 Weak current College 】 infrared thermometer measurement technology as well as the selection guide 】
Infrared temperature 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 imagingtechnology 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
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 uniquewindow 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 areas openOpen a 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
Infrared 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, etc.
2.2 thermal camera development
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 General imaging systems 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 frame picture response time fast enough, 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 oneGeneration 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.
3. infrared temperature measurement
3.2 infrared thermometer working principle
Understanding infrared thermometer works, technical indicators, environmental conditions and the operation and maintenance of the user in the proper selection and use of infrared thermometer. Infrared thermometer by the optical system, photoelectric detectors, signal amplifiers and signal processing, display the output. Optical system brings together its vision of infrared radiation energy, field of view of the size of the thermometer of optical parts and location decisions. Infrared energy is focused in photoelectric detector and transformed into the corresponding signal. The signal amplifier and signal processing circuitry in accordance with the instrument's internal algorithms and target emissivity correction after changes to the measured temperature value of the target. In addition, you should also consider the target and the thermometer are environmental conditions such as temperature, climate, pollution and noise and other factors on the performance indicators of impact and correction methods.
All temperature higher than absolute zero objects are kept to the surrounding space issue infrared radiation energy. Objects of infrared radiation energy of the size and distribution by wavelength — and its surface temperature is very closely related. Therefore, the object itself radiation measurement of infrared energy, will be able to accurately measure the surface temperature, this is the infrared radiation Thermometry is based on an objective basis.
Law of blackbody radiation: blackbody is an idealization of the radiator, it absorbs all wavelengths of radiation energy, did not reflection and through energy, its surface emissivity is 1. It should be noted that, in nature and does not exist the real bold, but to find out what the and infrared radiation distribution, in theory you must select the appropriate model, this is the body cavity of Planck's radiation of quantum oscillator model to export the Planck's law of blackbody radiation, wavelength said of blackbody radiation spectra, this is all theory of infrared radiation, therefore calls the law of blackbody radiation.
Object emissivity effect on radiation Thermometry: nature of the actual object, not a blackbody. All the actual object of radiation wavelength than dependent radiation and temperature of a body, and form the object of material types, preparation method, thermal process, as well as surface and environmental conditions and other factors. Therefore, in order to make the blackbody radiation law applies to all actual objects, you must introduce a and material properties and surface condition of scaling factors, namely the emissivity. The coefficient indicates that the actual object in thermal radiation and how closely the blackbody radiation, its value is zero and less than 1 between the numeric value. According to the radiation law, as long as known material emissivity, know any objects of infrared radiation.
Main factors influencing emissivity yarn in: material type, surface roughness, physical and chemical structure and material thickness, etc.
When using infrared radiation thermometer to measure the target temperatures must first measure goals in the wavelength range of infrared radiation, and the thermometer calculated temperature of the measured object. Monochrome thermometer and band in proportion to the amount of radiation; two color Pyrometer with two wavelengths of radiation is proportional to volume ratio.
Infrared system: infrared thermometer by the optical system, photoelectric detectors, signal amplifiers and signal processing, display the output. Optical system brings together its vision of infrared radiation energy, field of view of the size of the thermometer of optical parts and its location. Infrared energy is focused in photoelectric detector and transformed into the corresponding signal. The signal amplifier and signal processing circuit, and in accordance with the instruments of the algorithm and target neiliao emissivity correction after changes to the measured temperature value of the target.
3.3 infrared thermometer performance
InfraredThermometer is fired by receiving target objects, reflection and transmission of energy to measure the surface temperature. Thermometer probe components within the acquisition of energy information to the microprocessor to process, and then converted to display the temperature readings. In laser aiming device models, laser aiming device only aiming to use.
Its performance instructions such as table 1.
Temperature range-32 ° c-400 ° c display resolution 0.1 ℃ (< 199.1 ° c)
Precision 23 ℃ ± 1% of the working temperature range 0-50 ℃
Repetitive 23 ℃ ± 1% to 30 ° c relative humidity 10-95%
Response time 500ms power 9V
Response spectra 7-18micron size 137 × 41 × 196mm
Maximum display Have weight 270g
Emissivity 0.95Preset waterproof under fire forces require special production
Table 1 performance infrared thermometer
In order to obtain an accurate temperature reading, thermometer and the distance between the test target must fit within the scope of the so-called "light point size" (spot size) is the thermometer measuring points of the area. Your distance goal spot size further. The right picture shows the distance and spot size ratios, or D:S. In laser aiming device typethermometer, laser point above the target Center, 12mm (0.47) distance of bias.
Measure distance and spot size
In measuring distances, should ensure that objective diameter equal to or greater than the point size of respondents. The image on the right labeled "objects", no. 1 (object 1) and the distance between the measuring instrument is, because the target ratio was slightly larger metering point size. The "object", no. 2, distances, because the target is less than the spot size instrumented, thermometer measurement with the background objects, which reduces the accuracy of the readings.
4. infrared thermometer right choice
Select infrared thermometer can be divided into three areas:
(1) performance indicators, such as temperature, spot size, working wavelength, measurement accuracy, window, display, and output, response time, protection, accessories, etc.;
(2) environmental and working conditions, such as temperature, window, display, and output, protection, accessories, etc.;
(3) other options, such as easy to use, maintenance and calibration of performance and price, but also on the thermometer of choice to produce certain effects.
As the technology and development, the infrared thermometer is the best design and development provides users with a variety of functional and versatile instrument, expanded choice. Other choices, such as easy to use, maintenance and calibration of performance and price. In the select thermometer model should first determine the measurement requirements, such as the measured target temperature, measured the target size, measuring distance, measured target materials, the target environment, response speed, accuracy, using portable or on-line, and so on; in an existing various types of thermometer contrast, elect to meet the requirements of the instrument model; in many to meet the above requirements model, select the performance, functionality, and price of best match.
4.1 determine temperature measuring range
Determine the temperature measuring range: measuring range is the thermometer one of the most important performance indicators. If Raytek (Raytek) product range is-50 ° c-+ 30 ° c, but this is not a type of infrared thermometer. Each type of thermometer has its own specific temperature range. Therefore, users of the measured temperature range should be considered accurate, comprehensive, neither too narrow nor too wide. According to the law of blackbody radiation spectrum of short wavelength radiation caused by temperature changes will exceed energy by emissivity errors are caused by changes of the radiation energy, therefore, when you try to use temperature short is good. In General, the more narrow temperature range, monitoring the temperature, the higher the resolution of the output signal, precision reliability, easy to solve. Wide measuring range, temperature measurement accuracy will decrease. For example, if the measured target temperature of 1000 degrees Celsius, first determine the on-line or portable, if it is portable. Meet the temperature of the model, such as 3iLR3, 3i2M, 3i1M. If accuracy is important, it is best to choose 2 m or 1M model, because if you choose to use the 3iLR-measurement range is wide, the high temperature measuring performance is less; if a user in addition to measuring 1000 degree Celsius target, but also take care of low-temperature objective, then had to select 3iLR3.
4.2 target size
Infrared thermometer in accordance with the principle can be divided into a monochrome thermometer and two color pyrometer (radiation colorimetric thermometer). For monochrome thermometer, temperature, measured target area should be filled with thermometer field of view. Recommended that the measured size of the target size more than 50% of the field as well. If the target size is less than the field of view, the background radiation energy will enter the thermometer of acoustic interference temperature readings are supported, resulting inerrors. Conversely, if the target field is larger than the thermometer, thermometer is not affected by the measure the area outside the influence of the background. For colorimetric thermometer, its temperature is composed of two independent of wavelength band radiation energy ratio. So when the measured goal is very small, not full field of view, the measurement channel on fumes, dust, barrier, there is the radiation energy attenuation, are incorrect measuring results have a significant impact. For small and is in motion or vibration of target, colorimetric thermometer is the best choice. This is because light diameter small, flexible, and can be bent, barrier and collapse of channel transmission light radiation energy.
For Raytek (Raytek) two-color pyrometer, temperature is composed of two independent of wavelength band radiationEnergy ratio. So when the measured goal is very small, no full-scene, measuring path on fumes, dust, blocking on radiation energy attenuation, will not affect the measurement results. Even energy attenuation up to 95% of cases, you will still be able to guarantee the required temperature measurement accuracy. For target small, and is in motion or vibration of goals; sometimes depending on venue motion, or may remove part of the target field, under these conditions, the use of two-color thermometer is the best choice. If the thermometer and the destination is not possible to directly target, measuring channel bending, narrow, blocked etc., two-color fiber optic thermometer is the best choice. This is due to its diameter is small, flexible, and can be bent, barrier and collapse of channel transmission light radiation energy, so you can measure difficult to access, conditions or toward the goal of the electromagnetic field.
4.3 determine distance coefficient (optical resolution)
Distance coefficient determined by D:S ratio, i.e. the thermometer probe to the target distance between D and the measured object diameter ratio. If the thermometer as environmental conditions must be installed away from the target, but also to measure small goals, you should select the high optical resolution of the thermometer. Optical resolution is higher, i.e. increase D:S ratio, thermometer, the higher the costs. Raytek IR thermometer D:S range from 2: 1 (low distance coefficient) to more than 300: 1 (high distance coefficient). If the thermometer off target, and the destination is low, you should select the high distance coefficient of the thermometer. For fixed focal length of the thermometer, the focus in the optical system for spot minimum position, near-and far from the spot will increase the focus location. There are two distance coefficient. Therefore, in order to be able to close and far away from the focus on accurate temperature measurement of distance, measured target size should be larger than the focus at the spot size, zoom thermometer has a minimum focus position, according to the target distance. Increasing the energy received D:S, reducing, if not increase the receive diameter, distance coefficient D:S difficult, this would increase the cost of equipment.
4.4 determine wavelength range
The target material and surface properties of emissivity determines the thermometer of Spectra corresponding wavelength for high reflectivity alloy material, with low or changing emissivity. In the high temperature area, the best measurement of metals is the near-infrared wavelengths, optional 0.8 ~ φ1.0 μ m. Other temperature can choose 1.6 2.2 m, μ μ μ m m and 3.9. Because some of the material in certain wavelengths is transparent to infrared energy will penetrate these materials, such materials should choose special wavelength. If the internal temperature measuring glass selection φ1.0 m, 2.2 μ μ μ m and 3.9 m (measured to very thick glass or through) wavelength; measuring glass surface temperature selection ¦µ5.0 μ m; low temperature measuring 8 to 14 in selection of μ m. If measurement polyethylene plastic film selection 3.43 μ m, polyester class selection of 4.3 m or 7.9 μ μ m, thickness exceeding 0.4mm of μ m 8-14. If the log fire in CO for narrowband 4.64 μ m, measuring NO2 flame of 4.47 μ m used.
4.5 determine response time
Response time means infrared thermometer on the measured temperature reaction speed, defined as reaching the final reading of 95% energy need time, and photoelectric detector and signal processing circuits and displays system time constant. Raytek (Raytek) new infrared thermometer up to 1ms response time. This is not as simple as contacting temperature measurement method is much faster. If the target of the campaign quickly or measurement of rapid heating of the target that you want to use quick response infrared thermometer, otherwise can not reach enough signal response, will reduce the measurement precision. However, not all applications require quick response infrared thermometer. For static or target thermal process exists when the thermal inertia, the thermometer of response time to relax. Thus, the infrared thermometer response time to select and test goals. Determine response time, depending on the target's movement speed and the speed of temperature change objectives. For static goals or objectives ginseng in thermal inertia, or existing control device speed limits, the thermometer of response time to relax.
4.6 signal processing functions
In view of the discrete process (such as a parts production) and continuous process is different, so called infrared thermometer has more signal processing functions (such as peak hold, Gu values, average) are available, such as measuring conveyor belt bottle, we maintain with peak, its temperature of output signals transmitted to the controller. Otherwise the thermometer readout bottle between low temperature value. If the peak keeps the set temperature is slightly longer than the response time interval between the bottle so that at least one bottle is always in a measurement.
4.7 environmental conditions to consider
Thermometer environment conditions on measurement results have great impact, should be considered and appropriate solution, otherwise it will affect the measuring accuracy even causes damage. When the ambient temperature is high, the presence of dust, smoke and steam conditions, the choice of manufacturers of protective sleeve, water cooling and air cooling system and air blowing machine and other attachments. These attachments can effectively address the environmental impact and to protect the thermometer for accurate temperature measurement,. In determining the attachment, the requirements for Standardization service as possible, to reduce installation costs. When noise, electromagnetic fields, vibration or difficult to access environmental conditions or other conditions, smoke, dust or other particles reduce measuring energy letter signals, fibre-color thermometer is the best choice. Colorimetric thermometer is the best choice. In noise, vibration, electromagnetic fields and difficult to access in environmental conditions or other conditions should select light colorimetric thermometer.
In sealed or dangerous materials (such as containers or vacuum tank), thermometer observing through the window. Materials must be of sufficient strength and energy through the thermometer working wavelength range. To determine whether it requires the operator through the window to observe, to select the appropriate installation position and window material, to avoid interaction. In low-temperature measurement applications, often using Ge or Si material as window, impermeable to visible light, the human eye cannot, through observation of the target window. If an operator needs through windowMouth goal should be used in both through infrared radiation through visible light optical materials, such as should be both through infrared radiation through visible light optical materials, such as ZnSe or BaF2, etc. as window material.
When the thermometer work environment exists of inflammable gas, you can use the intrinsic safety type infrared thermometer, resulting in a concentration of the flammable gas, environment, security measurement, and monitoring.
In environmental conditions and complex cases, you can select the measuring head and display separate systems for easy installation and configuration. To select the existing control device matching signal output form.
4.8 infrared radiation thermometer calibration
Infrared thermometer calibration must pass in order to enable it to properly display the temperature of the measured object. If the thermometer in the use of a temperature variance, then returned to the manufacturers or repair center calibration again.