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1、UnitFourteenControlandBuildingAutomationSystemWhatisanintelligentbuilding?SchematicDiagramofanIntelligentBuildingSystemUptonow,therehasnotbeenauniversallyaccepteddefinitionforanIntelligentBuilding.MostexistingdefinitionsofIBaroundtheworldcentreontheneedforabuildingtobesuitablefortheoccupantstoworka
2、ndliveinsafely,comfortably,effectivelyandefficiently.“Intelligentbuildingissomethingthatmakestupidpeoplefeelnotasstupidastheyare”.IntelligentBuildingcanbringusReducedResourceConsumptionBothhomeandbuildingtechnologyoffertremendouspotentialsavingsthroughintelligentcontrols.OptimizedConvenienceandMore
3、ComfortApartfromminimizingconsumptioncosts,privatehomeownerswillbeinterestedinhigherlevelsofconvenience,safetyandsecurity.SmartHomeisanintegrationofvarioussystemsathomesuchassecurity,homeautomation,lightingcontrol,CCTVandentertainmentsystemwhichiscoordinatedbyasmarthomecontrollerandcontrolledbyuser
4、susingvariouscentralizedcommandinterfacessuchasatouchscreens,keypads,universalremotecontrollers,internetbrowser,telephone,andevenyourLCDTVscreen.SmartHomeSystemsCCTV:ClosedCircuitTelevisionCCTV:ChinaCentralTelevisionOn/offControlThecontroldevicecanbepositionedonlytoamaximumorminimumstate(e.g.,onoro
5、ff).BecauseOn/offcontrolissimpleandinexpensive,itisusedextensivelyforbothindustrialandcommercialcontrol.AtypicalhomethermostatthatstartsandstopsafurnaceisanexampleofOn/offaction.FloatingControlDead(neutral)zone盲区停滞区Infloatingcontrol,thecontrollercanperformonlytwooperations—movingthecontrolleddevice
6、towardeitheritsopenorclosedposition,usuallyataconstantrate.Generally,aneutralzonebetweenthetwopositionsallowsthecontrolleddevicetostopatanypositionwhenthecontrolledvariableiswithinthedifferentialofthecontroller.Whenthecontrolledvariablefallsoutsidethedifferentialofthecontroller,thecontrollermovesth
7、econtrolleddeviceintheproperdirection.openshutTimeUpperlimitLowerlimitneutralzoneTemperatureValvesetpointcontrolledvariableproportionalbandoutputoffsetProportionalcontrolrequiresacontinuouslyvariableoutputo
