Application-of-PLC-in-the-Elevator-Control-System-

ApplicationofPLCintheElevatorControlSystemofIntelligenceBuildingLiFenglian1RenQinglian21TaiYuanUniversityofTechnology,Taiyuan,China,2TaiYuanUniversityofscienceandTechnology,Taiyuan,China,Phone[phone]E-mail:[e-mail]:Thepapermainlydiscussesonesubsystemofintelligencebuildingsystem:theelevatorcontrolsystem.ThePLCstrongabilityininterferenceandsoonmakestheelevatorindustryoneafteranothertoapplythePLCtotheelevatorcontrolsysteminordertoreplacetherelaybeingusedintraditionalelevatorcontrolsystem.TheApplicationofPLCintheElevatorcontrolsystemreducesthebreakdownrateandefficientlyimprovestheoperatingreliabilityoftheelevatorwithsafety.Thestructureofsystemisalsosimpleandtightlypacked.Theworkingprincipleoftheelevatorcontrolsystemis:ThespotcontrolinformationissendintotheＰＬＣfromthecustomerinputdevicesfirstly,thenthePLCcontrolcabinetisrequiredtosendoutthecontrolsignaltodrivetheequipmentsaccordingtothesystemdemands.Theelevatorcanthenproceedthehomologousactionaccordingtothecontrolrequest.ThepaperselectsＯＭＲＯＮcompany’sＣ200HEseriesPLC,introducingpartsofsignalhookupoftheelevatorcontrolsystemandexplainingthefunctionofthecontrolcabinet.Lastlytheautomationprogrammingisintroduced.Simulatedexperimentsenunciatesthatthedesignmethodisviable.Itcanmakethepersonneloftheindustrymanagementcentertolong-distancemonitorandcontroltheelevatorincontrolcenter,toconnecttheelevatorcontrolsystemwithintelligencebuildingindustrymanagementsystembyEthernetorspecial-purposenetworksuchasLonWorks.Theelevatorworkingstatecanalsobetimelywatched.Thesenotonlycanrealizescientificcentralizedmanagementoftheelevator,butalsocanlowertheelevatormaintenancecostetc.Itisoneofthedevelopingdirectionofintelligencebuildingelevatorcontrolsystem.Keywords:PLC;intelligencebuilding;elevatorcontrolsystem;workingprinciple;programdesignⅠ.IntroductionIn1980sThefirstintelligencemansionhadbeencompletedinAmerica,thenintelligencebuildinghasbeenabroadlytakenattentionsbythewholeworld.Theconceptofintelligencebuildinghasbeenputdifferentmeaningsalongwiththedevelopmentofsociety.Theearlystageintelligencebuildinghadbeenthoughtthatitisequaltotheintelligentmansion,butnowtheintelligencebuildingnotonlyincludestheintelligencemansionsbutalsoinvolvesintelligenceresidentialdistricts.Thispapermainlydiscussesonesubsystemofintelligencebuildingsystem:theelevatorcontrolsystem.Inintelligenceresidentialdistrictstheenterprise’sinformationmanagingsystemmainlytakeschargeofthethingswhichrelatedtothedailylife,forexamplesupervisingthedistrictequipments,managingvehicles,disposingcriticalsituationsandsoon.Theelevatorsupervisingandcontrolsystemisalsonecessarytotheintelligenceresidentialdistricts.Howtomakepeoplefeelsafe,stableandcomfortableandhowtosaveenergyresourcesandprotectenvironmentsandsoonarethebasicrequirementstotheelevatorcontrolsystem.PLCisacommonindustrycontroldevice.Itisaspecialindustrycontrolcomputerwhichhastheperfectfunctionandsimpleframe.ThePLCstrongabilityininterferenceandsoonmakestheelevatorindustryoneafteranothertoapplythePLCtothe1625elevatorcontrolsystem,inordertoreplacetherelaybeingusedintraditionalelevatorcontrolsystem.TheApplicationofPLCintheelevatorcontrolsystemreducesthebreakdownrateandefficientlyimprovestheoperatingreliabilityoftheelevatorwithsafety.Thispapermainlydiscussestheelevatorcontrolsystem’sworkingprinciples,thesystem’ssoftwareandhardwarerealizationmethodsandsoon.Ⅱ.TheWorkingPrincipleofElevatorControlSystemInFig.1theHardwareStructureGraphofElevatorControlSystemispresented.VelocityFeedbackDevicesInputFig.1TheHardwareStructureGraphofElevatorControlSystemTheWorkingPrinciplesofElevatorControlSystemarestatedasfollows:ThespotcontrolinformationissendintothePLCfromthecustomerinputdevicesfirstly,thenthePLCcontrolcabinetisrequiredtosendoutthecontrolsignaltodrivetheequipmentsaccordingtothesystemdemands.Theelevatorcanthenperformthehomologousactionaccordingtothecontrolrequest.Therearevelocityfeedbackdevicesinsystem,whichadoptmeasurevelocitygeneratorstoprovidetheelevatorvelocitiesandgenerallyareinstalledinthetailoftowmotors.Sothisisafeedbackcontrolsystem,whichcanimprovethesystem’scontrolprecision.Ⅲ.TheHardwareConfigurationofControlSystemItisnotnecessarytodointerfacecircuitintheelevator’sPLCcontrolsystem.WhatweshoulddoistosendthesignalstoPLCdigitalinputterminals.Thesignalsincludeinsideandoutsidecallingsignals,floorlocationinspectingsignals,limitinglocationsignals,openingandshutdowntheelevatordoorsignalsetc.TheDCpowerwhichisprovidedtoPLCcanbeusedasindicatorlightpower.ThePLCoutputpointscanbedirectlyusedtocontroltransducersforthepurposeofelectricalmotor’spositiveturnandreverse,stopandcontroleachsegmentvelocityandsoon.ＯＭＲＯＮcompany’sＣ200HEseriesPLChasbeenselectedasmajorcontrolconfigurationaccordingtotheinput/outputpointsandthelengthofuser’sprogram.Ontheotherhandwealsoconsiderthatthesystem’sfunctioncanbeexpandedinthefuture.Ｃ200HEseriesPLC,whoseperfectfunctionandstrongreliability,canmeetthesedemandsatpresent.Moreover,inputandoutputdevicesareneededinelevatorcontrolsystem,besidesthePLC,system’sma