American Standard CH530 manual Control Sequence of Operation

Page 69

Control Sequence of Operation

Now that the compressor motor (4M1) is running in the ‘‘Delta’’ configuration, the inlet guide vanes will modulate, opening and closing to the chiller load variation by operation of the stepper vane motor actuator (4M2) 4M4 (extended capacity) to satisfy chilled water setpoint. The chiller continues to run in its appropriate mode of operation: Normal, Softload, Limit Mode, etcetera. As explained in the General Information section.

If the chilled water temperature drops below the chilled water set point by an amount set as the ‘‘differential to stop’’ setpoint, a normal chiller stop sequence is initiated as follows: (Refer to Figure 10.)

1.The inlet guide vanes are driven closed for 50 seconds.

2.After the 50 seconds has elapsed, the stop relay (2A1-J10) and the condenser water pump relays (1A5- J2) open to turn off. The oil and refrigerant pump motor (4B3) will continue to run for 3 minutes post lube while the compressor coasts to a stop. The chilled water pump will continue to run while the Main processor module (1A22) monitors leaving chilled water temperature preparing for the next compressor motor start based on the ‘‘differential to start’’ setpoint.

If the STOP key is pressed on the operator interface, the chiller will

follow the same stop sequence as above except the chilled water pump relay (1A5-J2) will also open and stop the chilled water pump after the chilled water pump delay timer has timed out after compressor shut down.

If the “Immediate Stop” is initiated, a panic stop occurs which follows the same stop sequence as pressing the STOP key once except the inlet guide vanes are not sequence closed and the compressor motor is immediately turned off.

CDHF-SVU01C-EN

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Contents X39640670030CDHF-SVU01C-EN Read these carefully Contents Literature change General InformationAbout this manual Unit NameplateGeneral Information = 560 3 stage 935 2 stage Y = 500 3 stage 835 2 stage Control Optional Packages Commonly Used AcronymsGeneral Duplex unit components front view OverviewGeneral Duplex unit components 2 stage compressor Compressor 1 or 2 2 Stage Cooling CyclePressure enthalpy curve 3 stage compressor Pressure enthalpy curve 2 stage compressor DynaView Human Interface TechView Chiller Service ToolSoftware Operation Overview Diagram Power Up DiagramSoftware States Figure Timeline Text FiguresStaging Second Compressor On CDHE/F/G sequence of operation auto to runningSatisfied Setpoint Staging Second Compressor OffCDHF/G sequence of operation lead 1/lag CDHE/F/G sequence of operation lead 2 lag Fixed Sequence Compressor 2 / CompressorCDHF/G sequence of operation equalize starts and hours Sequencing Balanced Starts and HoursCDHF/G sequence of operation combined start Simultaneous Compressor Start/ StopRestart Inhibit Restart Inhibit Start to Start Time SettingRestart Inhibit Free Starts Clear Restart InhibitOil and Refrigerant Pump Surface TemperaturesOil refrigerant pump circuit 1 or 20 100 percent RLA Base Loading Control AlgorithmGeneral Information Sequence of operation ice making running to ice making Ice Machine ControlHot Water control Unit Control Panel UCP Control Panel Devices and Unit Mounted DevicesUnit Control Panel UCP User-defined language support Variable water flow through the evaporatorDynaView main processor Operator InterfaceOperator Interface How It Works Chiller Stop Prevention/Inhibit FeatureTop Level Mode Description System Reset Reference Circuit Operating Mode Chiller Operating ModeMain Screen Main Screen Data Fields TableDiagnostic Screen Back button provides navigation back to the chiller screen Operator Interface Reports Report MenuReport name Circuit Evaporator Report name System EvaporatorReport name System Condenser Report name Circuit CondenserReport name System Ashrae Chiller Log Historic Diagnostics LogHeader Screen Setting Tab screens provides a userChiller Feature SettingsCircuit Mode Overrides System Mode OverridesDisplay Settings PurgeOperator Interface Operator Interface Operator Interface Operator Interface Operator Interface Inter Processor Communications IPC3 Interprocessor CommunicationIPC3 Definitions Bus Management BindingControl panel components layout Control System ComponentsControl System Components Control Panel Devices Head Relief Request Output Machine Shutdown Manual Reset MMRMaximum Capacity Relay Compressor Running RelayExop Refrigerant Monitor Input 1A17Trmm TRM4 Tracer Comm 4 interface Cdrp Condenser Refrigerant Pressure OutputEpro Enhanced Protection Cdrp Refrigerant Pressure Output Option 1A15 Temperature basedCondenser Pressure Output Pressure basedRefrigerant Differential Pressure Indication Output Percent RLA Output Gbas Generic Building Automation SystemExternal Chilled Water Setpoint Ecws Module CharacteristicsExternal Current Limit Setpoint Wpsr WFC Water Pressure Sensing Option1A8, 1A9, 1A11, 1A12 Quad Relay Output Status 1A13, 1A18, 1A19, 1A20 Dual Binary input module1A14 Communication interface Module Recommended Length to Run external Output signals 1A15, 1A16, 1A17, 1A21 Dual Analog Input/output ModuleAnalog Input Unit mounted devices Control System Components Control System Components Control Sequence of Operation Electrical SequenceUCP and Wye-Delta Starter Control Circuits Delay time 200 msec. Opens 2K1 Control Sequence of Operation Test and start timing sequence Control Sequence OperationAFD Machine Protection Adaptive Control Momentary Power Loss MPL ProtectionOverload trip time versus percent RLA Current Overload ProtectionPhase Loss Protection Current Limit ProtectionReverse Rotation Protection Differential to Start or Stop SoftLoadingMinimum and Maximum Capacity Limit Evaporator Limit Leaving Water Temperature CutoutHead Relief Relay Low Refrigerant Temperature CutoutCutout strategy Condenser Limit Restart Inhibit High Vacuum Lockout Oil Temperature Control Outdoor Air Temperature Controls Chilled Water Reset CWRMaximum Reset Return WaterDegrees of Reset Values for start reset typesConstant Return EquationOutdoor air temperature versus degrees of reset Reset RatioReset function for return CWR Reset Ratio = 50% Return CWR Unit Start-Up Procedures Unit StartupDaily Unit Start-Up Toxic Hazards Live Electrical ComponentsSeasonal Unit Start-Up ModeUnit Shutdown Unit Shutdown ProceduresOil Pump Heater Operation Seasonal Unit ShutdownDaily Maintenance and Checks Periodic MaintenanceMoisture Contamination Record Keeping FormsNormal Chiller Operating Characteristics Weekly MaintenanceHazardous Voltage w/Capacitors Every 3 MonthsAnnual Maintenance Off-Season MaintenanceOil Change Procedure Oil MaintenanceHeater Damage Compressor Oil ChangeReplacing Oil Filter Oil Filter ReplacementOil Supply System Problems MaintenanceOther Maintenance Requirements Hazardous Voltage w/ CapacitorsFront View with Refrigerant Pump Rotary valve in drain positionRefrigerant Charge Contains RefrigerantLeak Testing Recovery and Recycle ConnectionsCleaning the Condenser Proper Water TreatmentCleaning the Evaporator Control Settings AdjustmentsUnit Corrosion Damage Unit Preparation Purge System103 104 105 106 107 108 109 110 111 112 113 114 115 Trane