American Standard CH530 manual Simultaneous Compressor Start/ Stop

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General Information

Simultaneous Compressor Start/ Stop

Both compressors will start in close succession to minimize the time it takes for the chiller to reach full load. Some process applications need the chiller to start and generate capacity as fast as possible. This method will start both compressors, slightly staggered to prevent doubling of the current inrush, but will generally control the chiller as if there were only one compressor.

If the chiller is in the Auto mode and all interlocks have been satisfied, compressor 1 will be started based on the leaving water temperature rising above the “Differential to Start” setting. When compressor 1 is at speed, compressor 2 will start. Both compressors will run until water temperature falls below the differential to stop, at that time both compressors will be shut down.

Figure 15. CDHF/G sequence of operation: combined start

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Contents X39640670030CDHF-SVU01C-EN Read these carefully Contents General Information Literature changeAbout this manual Unit NameplateGeneral Information = 560 3 stage 935 2 stage Y = 500 3 stage 835 2 stage Commonly Used Acronyms Control Optional PackagesOverview General Duplex unit components front viewGeneral Duplex unit components 2 stage compressor Cooling Cycle Compressor 1 or 2 2 StagePressure enthalpy curve 3 stage compressor Pressure enthalpy curve 2 stage compressor TechView Chiller Service Tool DynaView Human InterfacePower Up Diagram Software Operation Overview DiagramSoftware States Figure Timeline Text FiguresCDHE/F/G sequence of operation auto to running Staging Second Compressor OnStaging Second Compressor Off Satisfied Setpoint CDHF/G sequence of operation lead 1/lag Fixed Sequence Compressor 2 / Compressor CDHE/F/G sequence of operation lead 2 lagSequencing Balanced Starts and Hours CDHF/G sequence of operation equalize starts and hoursSimultaneous Compressor Start/ Stop CDHF/G sequence of operation combined startRestart Inhibit Start to Start Time Setting Restart InhibitRestart Inhibit Free Starts Clear Restart InhibitSurface Temperatures Oil and Refrigerant PumpOil refrigerant pump circuit 1 or Base Loading Control Algorithm 20 100 percent RLAGeneral Information Ice Machine Control Sequence of operation ice making running to ice makingHot Water control Unit Control Panel UCP Unit Control Panel UCPControl Panel Devices and Unit Mounted Devices Variable water flow through the evaporator User-defined language supportOperator Interface DynaView main processorOperator Interface Chiller Stop Prevention/Inhibit Feature How It WorksTop Level Mode Description System Reset Reference Chiller Operating Mode Circuit Operating ModeMain Screen Main Screen Data Fields TableDiagnostic Screen Back button provides navigation back to the chiller screen Operator Interface Report Menu ReportsReport name System Evaporator Report name Circuit EvaporatorReport name System Condenser Report name Circuit CondenserHistoric Diagnostics Log Report name System Ashrae Chiller LogSetting Tab screens provides a user Header ScreenFeature Settings ChillerSystem Mode Overrides Circuit Mode OverridesDisplay Settings PurgeOperator Interface Operator Interface Operator Interface Operator Interface Operator Interface Interprocessor Communication Inter Processor Communications IPC3IPC3 Definitions Bus Management BindingControl System Components Control panel components layoutControl System Components Control Panel Devices Machine Shutdown Manual Reset MMR Head Relief Request OutputMaximum Capacity Relay Compressor Running RelayRefrigerant Monitor Input 1A17 ExopEpro Enhanced Protection Trmm TRM4 Tracer Comm 4 interfaceCdrp Condenser Refrigerant Pressure Output Temperature based Cdrp Refrigerant Pressure Output Option 1A15Condenser Pressure Output Pressure basedRefrigerant Differential Pressure Indication Output Gbas Generic Building Automation System Percent RLA OutputModule Characteristics External Chilled Water Setpoint EcwsExternal Current Limit Setpoint Wpsr WFC Water Pressure Sensing Option1A14 Communication interface Module 1A8, 1A9, 1A11, 1A12 Quad Relay Output Status1A13, 1A18, 1A19, 1A20 Dual Binary input module Analog Input Recommended Length to Run external Output signals1A15, 1A16, 1A17, 1A21 Dual Analog Input/output Module Unit mounted devices Control System Components Control System Components UCP and Wye-Delta Starter Control Circuits Control Sequence of OperationElectrical Sequence Delay time 200 msec. Opens 2K1 Control Sequence of Operation Control Sequence Operation Test and start timing sequenceAFD Momentary Power Loss MPL Protection Machine Protection Adaptive ControlCurrent Overload Protection Overload trip time versus percent RLAReverse Rotation Protection Phase Loss ProtectionCurrent Limit Protection Minimum and Maximum Capacity Limit Differential to Start or StopSoftLoading Leaving Water Temperature Cutout Evaporator LimitLow Refrigerant Temperature Cutout Head Relief RelayCutout strategy Condenser Limit Restart Inhibit High Vacuum Lockout Oil Temperature Control Controls Chilled Water Reset CWR Outdoor Air TemperatureMaximum Reset Return WaterValues for start reset types Degrees of ResetConstant Return EquationReset Ratio Outdoor air temperature versus degrees of resetReset function for return CWR Reset Ratio = 50% Return CWR Daily Unit Start-Up Unit Start-Up ProceduresUnit Startup Live Electrical Components Toxic HazardsSeasonal Unit Start-Up ModeUnit Shutdown Procedures Unit ShutdownOil Pump Heater Operation Seasonal Unit ShutdownPeriodic Maintenance Daily Maintenance and ChecksMoisture Contamination Record Keeping FormsWeekly Maintenance Normal Chiller Operating CharacteristicsHazardous Voltage w/Capacitors Every 3 MonthsOff-Season Maintenance Annual MaintenanceOil Maintenance Oil Change ProcedureHeater Damage Compressor Oil ChangeOil Filter Replacement Replacing Oil FilterMaintenance Oil Supply System ProblemsOther Maintenance Requirements Hazardous Voltage w/ CapacitorsRotary valve in drain position Front View with Refrigerant PumpContains Refrigerant Refrigerant ChargeRecovery and Recycle Connections Leak TestingCleaning the Condenser Proper Water TreatmentUnit Corrosion Damage Cleaning the EvaporatorControl Settings Adjustments Purge System Unit Preparation103 104 105 106 107 108 109 110 111 112 113 114 115 Trane