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TECHNOLOGYANDAPPLICATIONOFFIELDBUSCONTROLSYSTEMINTELLIGENTEQUIPMENTCONSTRUCTEDMEASUREMENTANDCONTROLSYSTEMFCSRCONSTRUCTEDFCSREMOTEDIAGNOSISANDSERVICECENTEROFINTELLIGENTCONTROLLEROFPUMPANDVALVECONSTRUCTEDFCSTRAININGCENTEROFINTELLIGENTCONTROLLEROFPUMPANDVALVEFOUNDEDMASSPRODUCTIONRPROCESSCONTROLSYSTEMTRAFFICCONTROLBUILDINGAUTOMATIONFEATURESFIELDBUSCONTROLSYSTEMISLOWLEVELLOWBANDWIDTHDIGITALCOMMUNICATIONANDCONTROLNETWORKININDUSTRIALSYSTEMASWELLASOPENSYSTEMCONNECTINGMICROCOMPUTERIZEDAPPEARANCEINTELLIGENTINSTRUMENTANDCONTROLLERAREEQUALTOMICROCOMPUTERTHEYMAKEUPNETWORKWITHFIELDBUSCONTROLSYSTEMASTHELINKSTOCOMPLETEDIGITALCOMMUNICATIONANDOTHERTASKS2DIFFERENCEBETWEENFCSANDDCS,FCSISUPDATEDCONTROLSYSTEMAFTERDCSINTEGRATEDWITHDIGITALCONTROLSYSTEMANDDISTRIBUTINGCONTROLSYSTEMITSOLVESTHEPROBLEMTHATINTRADITIONALDCS,DEVICESMADEBYDIFFERENTMANUFACTURERSCANNOTBECONNECTEDTHEYCANTREALIZEEXCHANGEANDOPERATIONTOORGANIZEANNETWORKSYSTEMWITHWIDERRANGEOFINFORMATIONSHARINGITCONQUERSTHEDEFECTTHATSPECIALCLOSEDSYSTEMFORNETWORKSHOULDBEUSEDFORCOMMUNICATIONINDCSTOREALIZEVARIOUSFUNCTIONSOFINTEGRATEDAUTOMATIONITTURNSTHEDISTRIBUTINGSTRUCTURECOMBININGCONCENTRATIONWITHDECONCENTRATIONINDCSINTONEWTYPEFULLDISTRIBUTINGSTRUCTUREITRELEASESTHECONTROLFUNCTIONTOTHEFIELDTHOROUGHLYANDMAKESITPOSSIBLETOREALIZEBASICCONTROLFUNCTIONBYMEANSOFFIELDBUSEQUIPMENTITSELFFCSBREAKSTHETRADITIONALSTRUCTUREFORMOFCONTROLSYSTEMTHETRADITIONALANALOGCONTROLSYSTEMADOPTSONETOONEEQUIPMENTTIEWIREANDPUTSUPCONNECTIONSRESPECTIVELYACCORDINGTOCONTROLLOOPFCSADOPTSINTELLIGENTFIELDEQUIPMENTTOPLACETHECONTROLMODULE,ALLINPUT/OUTPUTMODULESTHATUSEDTOBEINTHECONTROLCHAMBEROFDCSINTOFIELDEQUIPMENTSINCEFIELDEQUIPMENTHASABILITYTOCOMMUNICATE,THEFIELDMEASURINGANDTRANSFERRINGINSTRUMENTSCANTRANSFERSIGNALSTOACTUATINGMECHANISMSUCHASVALVEDIRECTLYITSCONTROLFUNCTIONCANBEFULFILLEDDIRECTLYONTHESPOTINDEPENDENTOFTHECOMPUTERORCONTROLMETERINTHECONTROLCHAMBER,WHICHREALIZESTHOROUGHDECENTRALIZEDCONTROLFCSADOPTSDIGITALSIGNALSTOREPLACEANALOGSIGNALSSOTHATMULTIPLESIGNALSINCLUDINGMULTIPLEOPERATINGPARAMETERVALUES,DEVICESTATUSANDFAILUREINFORMATIONCANBETRANSFERREDONAPAIROFCABLESMEANWHILE,ITCANGIVEPOWERSUPPLYTOSEVERALDEVICESNOSWITCHEDBLOCKFORANALOG/DIGITALORDIGITAL/ANALOGISNEEDEDBESIDESFIELDBUS3CHARACTERISTICSOFFCSOPENSYSTEMINTEROPERABILITYREPLACEABILITYOFDEVICESMADEBYDIFFERENTMANUFACTURERSINTELLIGENTIZEANDAUTONOMYFIELDEQUIPMENTCOMPLETINGBASICFUNCTIONSOFAUTOMATICCONTROLDECENTRALIZEDSYSTEMSTRUCTUREFIELDADAPTABILITYRELATIVELYSTRONGINTERFERENCEKILLINGFEATUREANDSAFETYINTELLIGENTIZEDLOCALEQUIPMENTCANSAVEINVESTMENTANDQUANTITYOFHARDWARESAVINGINSTALLATIONEXPENSESANDCABLESSAVINGDAILYMAINTENANCEEXPENSESENHANCINGACCURACYANDRELIABILITYOFSYSTEMENHANCINGINITIATIVENESSOFSYSTEMINTEGRATIONFORUSERS4DEVELOPMENTBACKGROUNDANDTRENDOFFIELDBUSCONTROLSYSTEM,WITHTHERAPIDDEVELOPMENTOFCOMPUTERANDCOMPUTERNETWORK,FCSHASBEENRAPIDLYDEVELOPEDASTHEINTERLINKEDCOMMUNICATIONNETWORKBETWEENTHEFIELDINTELLIGENTDEVICESINTHEFIELDOFPROCESSAUTOMATION,BUILDINGANDTRAFFICETCBECAUSEFCSMEETSTHENEEDSTHATINDUSTRIALCONTROLSYSTEMISDEVELOPINGINTHEWAYOFDECENTRALIZATION,NETWORKANDINTELLECTUALIZED,ITHASBECOMETHEFOCUSOFGLOBALINDUSTRIALAUTOMATIONANDBEENUNIVERSALLYCONCERNEDBYTHEWHOLEWORLDFCSHASCAUSEDGREATREVOLUTIONSONTHEASPECTSOFSYSTEMSTRUCTUREANDFUNCTIONSYSTEMFORTHECURRENTPRODUCTIONOFAUTOMATIONINSTRUMENT,DISTRIBUTINGCONTROLSYSTEMANDPROGRAMMABLECONTROLLERITISPREDICTEDTHATFCSWILLBETHEGENERALTRENDSINAVERYLONGTIMEINTHEFUTUREFORESURE2APPLICATIONOFRELAYTHEPRODUCTRELIABILITYGENERALLYREFERSTOTHEOPERATINGRELIABILITYITISDEFINEDASTHEABILITYOFACCOMPLISHINGTHESPECIFIEDFUNCTIONUNDERPRESCRIBEDCONDITIONSANDINPRESCRIBEDTIMEITCONSISTSOFINTRINSICRELIABILITYANDAPPLICATIONRELIABILITYTHEINTRINSICRELIABILITYISDETERMINEDBYPRODUCTDESIGNINGANDMANUFACTURINGTECHNIQUE,ANDTHEAPPLICATIONRELIABILITYISCONCERNEDWITHTHECORRECTAPPLICATIONOFUSERSANDTHESERVICESPROVIDEDBYTHEMANUFACTURERBEFOREANDAFTERSELLINGWHENUSINGRELAY,THEUSERSHOULDPAYATTENTIONTOTHEFOLLOWINGITEMS21COILAPPLIEDVOLTAGEITISBESTTOCHOOSETHECOILAPPLICATIVEVOLTAGEACCORDINGTOTHERATEDVOLTAGEINDESIGN,ORCHOOSETHEVOLTAGEACCORDINGTOTHETEMPERATURERISINGCURVEUSINGANYCOILVOLTAGETHATISLESSTHANTHERATEDVOLTAGEWILLAFFECTTHEOPERATIONOFTHERELAYTHECOILOPERATINGVOLTAGEREFERSTOTHEVOLTAGETHATISAPPLIEDBETWEENTHECOILTERMINALSTHEVOLTAGEVALUEBETWEENTHETWOTERMINALSMUSTBEGUARANTEED,ESPECIALLYWHENUSINGENLARGEMENTCIRCUITTOENERGIZETHECOILWHEREAS,ITWILLALSOAFFECTTHERELAYCHARACTERISTICSIFTHEAPPLIEDVOLTAGEEXCEEDSTHEHIGHESTRATEDVOLTAGEEXORBITANTVOLTAGEWILLBRINGEXORBITANTCOILTEMPERATURERISING,ESPECIALLYINHIGHTEMPERATUREAMBIENTEXORBITANTTEMPERATURERISINGWILLDAMAGETHEINSULATINGMATERIALANDAFFECTTHEWORKINGSAFETYOFRELAYFORMAGNETICLATCHINGRELAY,ENERGIZINGORRETURNPULSEWIDTHSHOULDNOTLESSTHAN3TIMESOFTHEOPERATINGORRETURNTIME,OTHERWISE,THERELAYWOULDBELEFTONTHEMIDDLEPOSITIONSTATEWHENUSINGSOLIDSTATECOMPONENTSTOENERGIZETHECOIL,THECOMPONENTSDIELECTRICSTRENGTHMUSTBEABOVE80V,ANDTHELEAKAGEOFCURRENTMUSTBEASLITTLEASPOSSIBLETOENSURETHERELAYTORELEASEENERGIZINGPOWERSOURCEUNDER110OFTHERATEDCURRENT,THEADJUSTINGRATIOOFTHEPOWERSO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数字化和网络互联化。上海ATON电气有限公司在基于DEVICENET网络协议研制了智能设备、智能测量法和只能控制系统，建立了工业化高新技术工程模型。这是2000年国家重点发展的高科技项目，并且由国家科技委员会认可。通过上海电气集团，上海ATON电气有限公司构造了汞和阀门的智能控制器的的生产线；创立了汞和阀门的智能控制器的现场控制系统的研发中心，通过和上海交通大学和上海大学的合作，建立了产品集成的研发基础；建立了汞和阀门的智能控制器的现场控制系统的远程诊断和服务中心；建立了汞和阀门智能控制系统的现场控制系统的培训中心；通过和上海交通大学洛氏实验室和计算机集成制造系统中心的合作，建立了集成产品研发的基础。1概要（1）现场总线控制系统就是应用于制造业中和应用微机和测量控制设备来实现多点双工的连续通信的系统。它也被称为是开放式、数字化和多点通信的低级控制网络。应用制造业中流程控制系统过程控制系统交通的控制和管理智能大厦特征现场总线控制系统应用于工业系统中的一中低级、低带宽的数字式化通信和控制的网络，同时它一种连接微机的开放式系统。智能仪表和控制器就相当于微型计算机。智能仪表和控制器组成现场总线控制系统作为一种链接来实现数字通信和其他的功能。2现场总线和集散控制系统的差别现场总线控制系统是综合集散控制系统、数字控制系统和分布式控制系统发展起来的系统。现场总线控制系统解决了集散控制系统中不同厂商生产的设备不能连接的传统毛病。在集散控制系统中，各设备之间不能实现相互间的数据交换和操作，以致不能组成一个网络实现远程的信息共享。现场总线控制系统克服了在集散控制系统通信中，为实现自动控制的各种功能时必须用到专用的封闭式系统来组建网络的缺点。现场总线控制系统改变了集散控制系统中将各分散系统组合在一块的结构，取而代之的是一中新型的完整的分布式结构。它完全解放了现场控制的功能，同时使通过现场总线设备来实现智能控制成为可能。现场总线控制系统突破了传统的控制系统的结构方式。在传统的控制系统中都是采用一对一的接线方式（即各个仪表之间是没有相互联系的），然后在根据控制回路来分别的连接这些设备的接线。现场总线控制系统采用智能的现场设备来作为控制模块，所有曾经用于集散控制系统中的输入/输出模块都用现场仪表代替。因为现场设备能实现通信功能，所以现场测量仪和传送仪可以将现场采集到的数据来直接控制比如阀门等这些机械装置。我们既可以通过现场的计算机来单独实现系统的控制功能，也可以通过控制在控制室的仪表来单独实现系统的控制功能，从而实现彻底的分散式控制。现场总线控制系统采用数字信号代替模拟信号，从而实现在一条电缆上传输更多的信号（包括真正工作的参数值、设备的运行情况和失败的信息）。同时，它可以同时给若干个设备供电。另外，除了现场总线外，系统中不在需要模/数或者数/模的转换卡。3现场总线控制系统的特性开放式系统互用性不同厂商生产的设备可以互相替用智能化现场仪表可以实现自动控制的基本功能分散式系统结构现场适应性强大的抗冲突性和安全性所需附加设备少安装费用和所用电缆少节省了每天的维护费用提高了系统的精确性和可靠性4现场总线控制系统的发展背景和发展前景随着计算机和计算机网络的高速发展，现场总线控制系统作为连接应用于过程自动化领域、智能大厦和交通系统中的智能设备间的通信网络，也已得到了快速的发展。因为现场总线控制系统的特点符合工业控制系统发展的分散化、网络化和智能化的要求，所以现场总线控制系统成为全球工业自动化的焦点并受到全球的普遍关注。现场总线控制系统已经引发了系统结构方面和自动化器械、分布式系统和可编程控制器方面产品的巨大革命。所以可预知在不久的将来很长一段时间里，现场总线控制系统将会成为必然趋势。2继电器的应用产品的可靠性通常十指操作的可靠性。它是这样定义的就是在规定的条件和规定的时间内完成特定的功能。它主要包括产品本身内在的质量的可靠性和产品在应用时的可靠性。产品内在的可靠性时由产品的设计和加工的技术决定的，而应用的可靠性则是和用户的正确使用和制造商在售前和售后提供的服务相关。在使用继电器的时候，用户应该注意以下几点21线圈工作电压选择线圈的工作电压最好是根据线圈本身的工作电压确定，或者是通过温度的商升曲线来选择。只要线圈的工作电压小于它的额定电压，那就会影响到继电器的正常运转。线圈的运转电压就是指加在线圈两端的电压。加在线圈两端的电压值必须足够大，特别是当电路实用放大电路给线圈两端加压的时候。然而，当工作电压超过最大的额定电压的时候同样会影响到继电器的工作特性。过高的电压会使线圈的温度升高的过快，特别是在高温的环境下。温度升高得过快会损坏绝缘材料和影响继电器工作的安全。比如说磁性吸合式继电器，充电（或放电）的时间脉宽应该大于线圈吸合（断开）的工作时间的三倍，或者继电器会处于半吸合半断开的状态。给线圈充电所用到的固定成分它的绝缘能力至少要能承受八十度以上的高压，同时漏电流应该尽可能小以保证线圈能够释放。所加电源地要求电流应该小于额定电流的110，电源的可调整率应该小于10（或者输出阻抗应该小于线圈阻抗的的5）。直流电压源的电压波动率应该小于5。而交流电压源必须是正弦波，同时波动率应该介于095125之间，波形失真度应该小于10。频率的变化应该介于1HZ或者是指定频率的1之间（取两者中值比较大的那个）。输出功率不应该小于线圈的损耗功率。22瞬时抑制现象和措施在线圈失电的瞬间，在线圈两边会产生大于线圈额定电压三十倍的反转电压，这对电子电路是非常不利的。通常可以使用一个瞬时抑制二极管或者电阻把最高反转电压抑制在50V以内。但是同时并联的二极管