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1、拟建中的阜阳市中国XXXX国际服装城依托中国XX国际服装城，拟建成为皖西北地区规格最高、规模最大、商务及功能最优的现代化、国际化服装专业市场，建设规模占地约128亩，建筑面积约25万平方米，项目总投资约5亿元人民币。经过1--2年的开发建设，能达到正常运营期的中国XX.XX国际服装城将吸纳全国和世界各地的经销商、代理商企业物流总部等500—1000家，预计年交易额实现68亿元人民币，每年实现税收8000—10000万元人民币，每年实现利润1.68亿元人民币，实现就业和创业人员约2万以上。ProgrammableLogicC
2、ontrollers(PLCS)1AboutProgrammableLogicControllers(PLCs)PLCs(programmablelogiccontrollers)arethecontrolhubsforawidevarietyofautomatedsystemsandprocesses.Theycontainmultipleinputsandoutputsthatusetransistorsandothercircuitrytosimulateswitchesandrelaystocontrolequip
3、ment.Theyareprogrammableviasoftwareinterfacedviastandardcomputerinterfacesandproprietarylanguagesandnetworkoptions.ProgrammablelogiccontrollersI/Ochannelspecificationsincludetotalnumberofpoints,numberofinputsandoutputs,abilitytoexpand,andmaximumnumberofchannels. N
4、umberofpointsisthesumoftheinputsandtheoutputs.PLCsmaybespecifiedbyanypossiblecombinationofthesevalues. Expandableunitsmaybestackedorlinkedtogethertoincreasetotalcontrolcapacity. Maximumnumberofchannelsreferstothemaximumtotalnumberofinputandoutputchannelsinanexpand
5、edsystem. PLCsystemspecificationstoconsiderincludescantime,numberofinstructions,datamemory,andprogrammemory. ScantimeisthetimerequiredbythePLCtocheckthestatesofitsinputsandoutputs. Instructionsarestandardoperations(suchasmathfunctions)availabletoPLCsoftware. Datam
6、emoryisthecapacityfordatastorage. Programmemoryisthecapacityforcontrolsoftware.AvailableinputsforprogrammablelogiccontrollersincludeDC,AC,analog,thermocouple,RTD,frequencyorpulse,transistor,andinterruptinputs. OutputsforPLCsincludeDC,AC,relay,analog,frequencyorpul
7、se,transistor,andtriac. ProgrammingoptionsforPLCsincludefrontpanel,handheld,andcomputer.Programmablelogiccontrollersuseavarietyofsoftwareprogramminglanguagesforcontrol. TheseincludeIEC61131-3,sequentialfunctionchart(SFC),functionblockdiagram(FBD),ladderdiagram(LD)
8、,structuredtext(ST),instructionlist(IL),relayladderlogic(RLL),flowchart,C,andBasic. TheIEC61131-3programmingenvironmentprovidessupportforfivelanguagessp
