资源描述：
《机电工程英语课件》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、Lesson13 ProgrammableLogicController可编程逻辑控制器SectionIWordsandPhrasesSectionIITextandTranslationSectionIIIExercisesandAnswers词英汉练EndNext答SectionIWordsandPhrasesactuator执行机构pneumatic［nju(:)5mAtik］adj.气动的，气力的n.气胎hydraulic［hai5drC:lik］adj.水力的,水压的，液压的n.液压传动装置relay［5ri:lei］n.[电工]继电器solenoid［5sEulinCid
2、］n.[电]螺线管proprietary［prE5praiEtEri］adj.所有人的：属于一个所有人或作为群体的所有人的，或与之有关的：cam［kAm］n.凸轮automate[5C:tEmeit]v.使自动化,自动操作initially[I5nIFElI]adv.最初,开头TopicAboveNextEndSectionIWordsandPhrasesladder[5lAdE(r)]n.梯子，梯形inspire[in5spaiE]vt.作为…原因或根源；引起；激励，鼓励：激发行动，促动traceout描绘出apprehension[7Apri5henFEn]n.担心，忧虑circ
3、uit[5sE:kit]n.电路load[lEud]n.负荷,重担,负载powersupply电源module[5mCdju:l]n.模数,模块,flexibility[7fleksE5biliti]n.弹性,适应性,柔韧性TopicAboveNextEndSectionIITextAprogrammablelogiccontroller,PLC,orprogrammablecontr-ollerisasmallcomputerusedforautomationofreal-worldprocesses,suchascontrolofmachineryonfactoryassembl
4、ylines.ThePLCusua-llyusesamicroprocessor.Theprogramcanoftencontrolcomplexseq-uencingandisoftenwrittenbyengineers.Theprogramisstoredinbattery-backedmemory1and/orEEPROMs2.PLCshavethebasicstructure,showninFigure13-1.Fromthefigure,thePLChasfourmainunits:theProgrammememory,theDatamemory,theOutputdev
5、icesandtheInputdevices.TheProgrammememoryisusedforstoringtheinstructionsforthelo-gicalcontrolsequence.Thestatusofswitches,interlocks,pastvaluesofdataandotherworkingdataisstoredintheDatamemory.TopicAboveNext汉EndSectionIITextThemaindifferencesfromothercomputersarethespecialinput/outputarrangement
6、s.TheseconnectthePLCtosensors3andactuators4.PLCsreadlimitswitches,temperatureindicatorsandthepositionsofcomplexpositioningsystems.Someevenusemachinevision.Ontheac-tuatorside,PLCsdriveanykindofelectricmotor,pneumaticorhydra-uliccylindersordiaphragms,magneticrelay-sorsolenoids.Theinput/outputarra
7、ngementsmaybebuiltintoasimplePLC,orthePLCmayhaveexternalI/OmodulesattachedtoaproprietarycomputernetworkthatplugsintothePLC.TopicAboveNext汉EndSectionIITextPLCswereinventedaslessexpensivereplacementsforolderauto-matedsystemsthatwoul
