【導(dǎo)讀】跟上不斷發(fā)展的工藝技術(shù)對工藝工程師來說是一向重大挑戰(zhàn)。再加上為了保持目前。迅速變化的監(jiān)測和控制方法的過程的要求，所以這項任務(wù)已變得相當(dāng)迫切。件、軟件和通信設(shè)備，以及最先進(jìn)的數(shù)字電路。其中最主要的工具，不過是新一代的紅。聯(lián)系在一起的高速數(shù)字技術(shù)的科學(xué)聯(lián)盟。這些文書被稱為智能傳感器，因為他們把微處。因為電路體積小，傳感器因此更小，簡化了在緊張或?qū)擂蔚貐^(qū)的安裝。從安全利益考慮，生產(chǎn)線將不得不關(guān)閉，并且。至少在降溫24小時之前改變和升級傳感器。今天，工藝工程師可以遠(yuǎn)程配置、監(jiān)測、處理、升級和維護其紅外溫度傳感器。如果智能傳感器由于高溫度環(huán)境、電纜斷裂或者未能組成部分而失敗了，其故障。該傳感器激活觸發(fā)報警停機，防止損壞產(chǎn)品和機械。具體程序要求使用的現(xiàn)場標(biāo)定、診斷、或來自傳感器制造商的實用軟件。以延長一個傳感器的工作壽命，可以真正的使一個智能傳感器智能化。達(dá)32個智能傳感器聯(lián)網(wǎng)。所有顯示的信息都來自經(jīng)由RS-485接口或

　　

【正文】 erature. If the process has a wide range of temperatures, and sensor readings need to match at three specific temperatures, the best choice is threepoint variable temperature calibration (see Figure 4). This technique uses the calibration temperatures to calculate two gains and two offsets. The first gain and offset are applied to all temperatures below a midpoint temperature, and the second set to all temperatures above the midpoint. Threepoint calibration is less mon than one and twopoint, but occasionally manufacturers need to perform this technique to meet specific standards. Field calibration software also allows routine diagnostics, including power supply voltage and relay tests, to be run on smart sensors. The results let process engineers know if the sensors are performing at their optimum and make any necessary troubleshooting easier. Conclusion The new generation of smart IR temperature sensors allows process engineers to keep up with changes brought on by newer manufacturing techniques and increases in production. They now can configure as many sensors as necessary for their specific process control needs and extend the life of those sensors far beyond that of earlier, “nonsmart” designs. As production rates increase, equipment downtime must decrease. By being able to monitor equipment and finetune temperature variables without shutting down a process, engineers can keep the process efficient and the product quality high. A smart IR sensor’s digital processing ponents and munications capabilities provide a level of flexibility, safety, and ease of use not achieved until now. How Infrared Temperature Sensors Work Infrared (IR) radiation is part of the electromagic spectrum, which includes radio waves, microwaves, visible light, and ultraviolet light, as well as gamma rays and Xrays. The IRrange falls between the visible portion of the spectrum and radio waves. IR wavelengths are usually expressed in microns, with the IR spectrum extending from to 1000 microns. Only the micron band is used for IR temperature measurement. Using advanced optic systems and detectors, noncontact IR thermometers can focus on nearly any portion or portions of the micron band. Because every object (with the exception of a blackbody) emits an optimum amount of IR energy at a specific point along the IR band, each process may require unique sensor models with specific optics and detector types. For example, a sensor with a narrow spectral range centered at microns is optimized for measuring the surface temperature of polyethylene and related materials. A sensor set up for 5 microns is used to measure glass surfaces. A 1 micron sensor is used for metals and foils. The broader spectral ranges are used to measure lower temperature surfaces, such as paper, board, poly, and foil posites. The intensity of an object39。s emitted IR energy increases or decreases in proportion to its temperature. It is the emitted energy, measured as the target39。s emissivity, that indicates an object39。s temperature. Emissivity is a term used to quantify the energyemitting characteristics of different materials and surfaces. IR sensors have adjustable emissivity settings, usually from to , which allow accurate temperature measurements of several surface types. The emitted energy es from an object and reaches the IR sensor through its optical system, which focuses the energy onto one or more photosensitive detectors. The detector then converts the IR energy into an electrical signal, which is in turn converted into a temperature value based on the sensor39。s calibration equation and the target39。s emissivity. This temperature value can be displayed on the sensor, or, in the case of the smart sensor, converted to a digital output and displayed on a puter terminal。