中央空调冷冻主机程序编程

CCT–ChillerPlantProgrammingLeoYipTopics•Chillercontrolcomponent•BasicChillerSequencing–Conditionforadd/downchiller–Chillerstart/stopsequencing–Conditionforequipmentselection–Conditionforequipmentselection–EquipmentTrip/Faulthandling•CCTProgrammingControlComponent&Signal1.MainHeaterTemperature,Flowrateforbuildingloadcalculation2.Chillerflowswitch&isolationvalveforchillermonitoring3.BypassvalvecontrolforsystemprotectionAuto/ManualFaultAlarmRunningStatusStart/StopControl4.Chiller&Pumpcontrol&monitoringChillerStartUpSequencing1.ChillerPlantStartUp(Nochillerisrunning)1.OpenValve2.Startpumpifvalvestatusisopen3.Startchillerifflowswitchisactivated123ChillerStartUpSequencing2.AddChiller(Atleast1chillerisrunning)1.OpenValve&Startpump2.Startchillerifflowswitchisactivated112ChillerShutDownSequencing1.ShutDownChiller(Atleast2chillersisrunning)1.StopChiller2.Afteratimedelay,stoppump&valve122ChillerShutDownSequencing1.ShutDownChillerPlant(Open1Chillerisrunning)1.StopChiller2.Afteratimedelay,stoppump3.Afteratimedelay,closethevalve.132ConditionforUpChiller1.Returnwatertemperature(12DegC)OR2.BuildingLoad=mC∆T(l/sx4.2x∆T)m=waterflowratec=waterdensity∆T=diff.temperatureofsupply&returnConditionforDownChiller1.Returnwatertemperature(12DegC)AND2.BuildingLoad=mC∆T(l/sx4.2x∆T)m=waterflowratec=waterdensity∆T=diff.temperatureofsupply&returnBuildingLoadSetPointUpSetPoint=90%xFullCapacityofRunningChillerDownSetPoint=50%xFullCapacityofRunningChillerConditionforEquipmentSelection•Notmanualmode,trip•Selectbyrunningtime–Startfirstwithlowesttotalrunninghours–StopfirstwithhighesttotalrunninghoursEquipmentTrip/FaultHandling•Ifequipmentistriporfaulttostart,startanotheravailableequipmentwithlowesttotalrunninghours.ProgramArchitecture-Outputhowmanydeviceneedtostart-Checkwhichequipmentisavailableornot-Selectthenextstart/stopequipmentbyequipmentrunningtime-Checkavailableofequipment-Startprocedureofequipment-CountthetotalrunninghourCCT-SequencerProactiveInternaltimer,bettersettozeroValueofUp&DownCCT–ChillerModuleChiller&valvestartcommandFaulttostartRuntimetimeFaulttostartcheckRuntimetimeTotalizationChillerEnableCheckCCT–CHWPModulePumpstartcommandFaulttostartcheckRuntimetimeTotalizationPumpEnableCheckCCT–1ValveStatusCCT–BuildingLoadSetPointCCT–EquipmentAvaliableCCT–UpCallCCT–DownCallCCT-LOAD