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輻射式高溫計(jì)工作原理
（圖一）
輻射高溫計(jì)分為安裝式和手持式，如圖一所示，安裝式是把輻射計(jì)安裝在爐體透射孔上，通過專用電纜連接至控制柜溫度測量儀表輸人端。而手持式由操作人員手持輻射計(jì)，對準(zhǔn)透射孔，直接測量爐子溫度。輻射高溫計(jì)是基于被測物體的輻射熱效應(yīng)進(jìn)行工作的。在整個(gè)波長范圍內(nèi)，依據(jù)輻射能量與溫度的關(guān)系，并用輻射系數(shù)修正后，來確定物體的實(shí)際溫度。全輻射式高溫計(jì)測量原理如圖二所示，被測物體發(fā)出的輻射能量通過物鏡1和補(bǔ)償光柵2聚焦投射到熱電堆3上，把溫度信號(hào)轉(zhuǎn)化為電信號(hào)，輸人到測溫儀表轉(zhuǎn)化為溫度顯示出來。熱電堆是由多支微型熱電偶串聯(lián)而成的，以得到較大的熱電勢。熱電偶的參考端補(bǔ)償采用雙金屬片控制的補(bǔ)償光柵，改變補(bǔ)償光柵的孔徑大小，就可以增加或減小射人的輻射能量，達(dá)到消除外部環(huán)境溫度的變化引起的測量誤差。
（圖二）
輻射高溫計(jì)與光學(xué)高溫計(jì)一樣是按絕對黑體進(jìn)行溫度分度的，因此用它測量非絕對黑體的物體溫度時(shí)，儀表上的溫度指示值將不是該物體的真實(shí)溫度，稱該溫度為此被測物體的輻射溫度。由于全輻射的輻射率總小于1，物體的輻射溫度低于實(shí)際溫度。在準(zhǔn)確知道物體的輻射率ε后，依據(jù)測到的輻射溫度Tp，利用下式便可計(jì)算出物體的實(shí)際溫度T。
智能式數(shù)字儀表已不需要人工計(jì)算實(shí)際溫度，只需把材料的全輻射率ε或材料的代碼輸人儀表，顯示出來的就是物體的實(shí)際溫度。
輻射式高溫計(jì)測量精度受環(huán)境的影響較大，比如周圍環(huán)境的輻射、測試距離、介質(zhì)吸收、發(fā)射及透過率等的變化都會(huì)嚴(yán)重影響精度，同時(shí)輻射率也很難預(yù)知，但因接收輻射能址大，測量靈敏度較高，而且結(jié)構(gòu)簡單，操作方便，測溫范圍寬，易自動(dòng)測量，故在電阻爐溫度測控中有著廣泛的應(yīng)用。
輻射式高溫計(jì)使用注意事項(xiàng)
使用輻射高溫計(jì)應(yīng)注意以下問題:
(1)在通過爐體上的透射孔測量溫度時(shí)，要清楚對準(zhǔn)測量的是工件溫度、電熱元件溫度還是其他爐內(nèi)部件的溫度，因?yàn)椴牧喜煌椛渎室膊煌瑴y量的實(shí)際溫度也有較大的差異。
(2)如果被測物體接近于黑體性質(zhì)，輻射溫度就近似等于實(shí)際溫度，可不進(jìn)行修正。
(3)輻射傳感器與被測物體之間不能存在灰塵、煙霧、水蒸氣等介質(zhì)，以免影響測量精度。
(4)物體的全輻射率ε受物體性質(zhì)、表面狀態(tài)、溫度和輻射條件的影響，為得到較為精確的測量溫度，應(yīng)盡量準(zhǔn)確地知道物體的全輻射率Fip
(5)使用環(huán)境溫度不要太高，避免熱電偶參考端溫度過高而引起測量誤差。
(6)由于輻射感溫器中熱電堆具有一定的熱惰性，一般要求穩(wěn)定4~12s，所以在測溫時(shí)觀察時(shí)間應(yīng)超過10s后再讀數(shù)。
(7)連接電纜從輻射傳感器中引出，導(dǎo)線應(yīng)放在金屬軟管中，保持有良好的電氣屏蔽和可靠的機(jī)械保護(hù)。
(8)從目鏡中所看到的被測對象的影像必須將熱電堆完全蓋上，以保證熱電堆充分接受被測對象輻射的能址。注意影像不能太大，否則熱電堆附近零件受熱，熱電偶參考端溫度升高，可能造成測量溫度偏低。
(9)在安裝后要定期清洗鏡頭灰塵，留意周圍環(huán)境有無機(jī)械振動(dòng)，探頭有無偏離，以保證正確反映電阻爐溫度。
(10)在使用某輻射高溫計(jì)前，一定要詳細(xì)閱讀使用說明書。
輻射式高溫計(jì)工作原理
Radiation pyrometer principle
（圖一）
(Chart)
輻射高溫計(jì)分為安裝式和手持式，如圖一所示，安裝式是把輻射計(jì)安裝在爐體透射孔上，通過專用電纜連接至控制柜溫度測量儀表輸人端。而手持式由操作人員手持輻射計(jì)，對準(zhǔn)透射孔，直接測量爐子溫度。輻射高溫計(jì)是基于被測物體的輻射熱效應(yīng)進(jìn)行工作的。在整個(gè)波長范圍內(nèi)，依據(jù)輻射能量與溫度的關(guān)系，并用輻射系數(shù)修正后，來確定物體的實(shí)際溫度。全輻射式高溫計(jì)測量原理如圖二所示，被測物體發(fā)出的輻射能量通過物鏡1和補(bǔ)償光柵2聚焦投射到熱電堆3上，把溫度信號(hào)轉(zhuǎn)化為電信號(hào)，輸人到測溫儀表轉(zhuǎn)化為溫度顯示出來。熱電堆是由多支微型熱電偶串聯(lián)而成的，以得到較大的熱電勢。熱電偶的參考端補(bǔ)償采用雙金屬片控制的補(bǔ)償光柵，改變補(bǔ)償光柵的孔徑大小，就可以增加或減小射人的輻射能量，達(dá)到消除外部環(huán)境溫度的變化引起的測量誤差。
Radiation high score for installation and portable, as shown in Figure 1, mounted the radiometer is arranged in the furnace body transmission hole, via a dedicated cable is connected to the control cabinet temperature measuring instrument inputs.While handheld operator handheld radiometer, alignment through perforation, direct measurement of the temperature.Radiation pyrometer is based on the measured object radiation effect to work.In the wavelength range, based on the radiation energy relationship with temperature, and radiation coefficient correction, to determine the object's actual temperature.Total radiation pyrometer measurement principle as shown in Figure two, the measured object the radiant energy emitted by an objective lens 1 and a compensating grating 2 focus projection to a thermopile 3, the temperature signal into electric signal, input to the thermometer into temperature display.Thermopile is composed of a plurality of miniature thermocouple which are connected in series, in order to get a larger thermoelectric potential.Thermocouple reference junction compensation adopts a bimetallic strip control compensation grating, grating to compensate the change of pore size, can increase or decrease the emission of radiant energy, to eliminate the external environment temperature changes caused by measurement error.
（圖二）
(Fig two)
輻射高溫計(jì)與光學(xué)高溫計(jì)一樣是按絕對黑體進(jìn)行溫度分度的，因此用它測量非絕對黑體的物體溫度時(shí)，儀表上的溫度指示值將不是該物體的真實(shí)溫度，稱該溫度為此被測物體的輻射溫度。由于全輻射的輻射率總小于1，物體的輻射溫度低于實(shí)際溫度。在準(zhǔn)確知道物體的輻射率ε后，依據(jù)測到的輻射溫度Tp，利用下式便可計(jì)算出物體的實(shí)際溫度T。
Radiation pyrometer with optical pyrometer blackbody temperature as by indexing, so that the measurement of absolute blackbody temperature of objects, the instrument's temperature indication value will not be the object of the true temperature, called the temperature to be measured the object the radiation temperature.As a result of the radiation rate is less than 1, the object radiation temperature is lower than the actual temperature.In the know exactly the object emissivity ε, based on the detected radiation temperature Tp, the type can be calculated from the object's actual temperature T.
智能式數(shù)字儀表已不需要人工計(jì)算實(shí)際溫度，只需把材料的全輻射率ε或材料的代碼輸人儀表，顯示出來的就是物體的實(shí)際溫度。
Intelligent type digital instrument has does not need the artificial calculation actual temperature, just the material total radiation ratio ε or material code input instrument, displayed objects is the actual temperature.
輻射式高溫計(jì)測量精度受環(huán)境的影響較大，比如周圍環(huán)境的輻射、測試距離、介質(zhì)吸收、發(fā)射及透過率等的變化都會(huì)嚴(yán)重影響精度，同時(shí)輻射率也很難預(yù)知，但因接收輻射能址大，測量靈敏度較高，而且結(jié)構(gòu)簡單，操作方便，測溫范圍寬，易自動(dòng)測量，故在電阻爐溫度測控中有著廣泛的應(yīng)用。
Radiation pyrometer measurement accuracy is affected by the environment greatly, such as ambient radiation, measuring distance, absorption, emission and transmittance changes will seriously affect the accuracy, while the radiation rate is also very difficult to predict, but due to receiving radiation can access, measurement sensitivity is high, and has the advantages of simple structure, convenient operation, temperature measurement range, easy automatic measurement, the resistance furnace temperature control in a wide range of applications.
輻射式高溫計(jì)使用注意事項(xiàng)
Radiation pyrometer use matters needing attention
使用輻射高溫計(jì)應(yīng)注意以下問題:
The use of radiation pyrometer should pay attention to the following questions:
(1)在通過爐體上的透射孔測量溫度時(shí)，要清楚對準(zhǔn)測量的是工件溫度、電熱元件溫度還是其他爐內(nèi)部件的溫度，因?yàn)椴牧喜煌椛渎室膊煌瑴y量的實(shí)際溫度也有較大的差異。
(1) in the transmission hole through the furnace body temperature measurement, to clear alignment is the measurement of the workpiece temperature, heating element temperature or other furnace component temperature, because of different materials, the radiation rate is also different, to measure the actual temperature also has bigger difference.
(2)如果被測物體接近于黑體性質(zhì)，輻射溫度就近似等于實(shí)際溫度，可不進(jìn)行修正。
(2) if the measured object close to the blackbody radiation properties, temperature is approximately equal to the actual temperature, can not revise.
(3)輻射傳感器與被測物體之間不能存在灰塵、煙霧、水蒸氣等介質(zhì)，以免影響測量精度。
(3) the radiation sensor and the object to be measured can not exist between the dust, smoke, water vapor and other media, so as not to affect the accuracy of measurement.
(4)物體的全輻射率ε受物體性質(zhì)、表面狀態(tài)、溫度和輻射條件的影響，為得到較為精確的測量溫度，應(yīng)盡量準(zhǔn)確地知道物體的全輻射率Fip
(4) the total emissivity ε object by object properties, surface condition, temperature and radiation conditions, in order to get more accurate measurement of temperature, should try to know exactly the object radiation rate Fip
(5)使用環(huán)境溫度不要太高，避免熱電偶參考端溫度過高而引起測量誤差。
(5) the use of environmental temperature not too high, avoid the thermocouple reference junction temperature is too high and cause measurement error.
(6)由于輻射感溫器中熱電堆具有一定的熱惰性，一般要求穩(wěn)定4~12s，所以在測溫時(shí)觀察時(shí)間應(yīng)超過10s后再讀數(shù)。
(6) due to the radiation temperature of a thermopile having a certain thermal inertia, general requirements and stable 4~12s, so the temperature is observed when time should be more than 10s after reading.
(7)連接電纜從輻射傳感器中引出，導(dǎo)線應(yīng)放在金屬軟管中，保持有良好的電氣屏蔽和可靠的機(jī)械保護(hù)。
(7) connected the cable from the radiation sensor leads, wire should be placed in a metal hose, to maintain a good electrical shielding and reliable mechanical protection.
(8)從目鏡中所看到的被測對象的影像必須將熱電堆完全蓋上，以保證熱電堆充分接受被測對象輻射的能址。注意影像不能太大，否則熱電堆附近零件受熱，熱電偶參考端溫度升高，可能造成測量溫度偏低。
(8) from the eyepiece as seen by the object image must be a thermopile completely cover, to ensure that the thermopile fully accept the measured object radiation can access.Pay attention to image can not be too large, otherwise the thermopile near heating parts, thermocouple reference junction temperature, may cause low temperature measurement.
(9)在安裝后要定期清洗鏡頭灰塵，留意周圍環(huán)境有無機(jī)械振動(dòng)，探頭有無偏離，以保證正確反映電阻爐溫度。
(9) after the installation to regularly cleaning the lens dust, pay attention to surrounding environment has no mechanical vibration, probe has no deviation, in order to ensure correctly reflect the resistance furnace temperature.
(10)在使用某輻射高溫計(jì)前，一定要詳細(xì)閱讀使用說明書。
(10) in the use of a radiation pyrometer, must read the instructions for use.
