American Standard CH530 manual Delay time 200 msec. Opens 2K1

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Control Sequence of Operation

When less than 5 seconds remain before compressor start, a starter test is conducted to verify contactor states prior to starting the compressor. The following test or start sequence is conducted for ‘‘Wye-Delta’’ starters: Also refer to Figure 24.

A. Test for transition complete contact open (2A1-J12-2) –160 to 240 msec. An MMR diagnostic will be generated if the contact is closed.

B. Delay time - 20 msec.

C. Close start contactor (2K1) and check for no current - 500 msec. If currents are detected, the MMR diagnostic ‘‘Starter Fault Type I’’ is generated.

D. Stop relay (2A1-J10-3 to 1) closes for one second for test “C” above.

E. Delay time - 200 msec. (Opens 2K1).

F. Close shorting contactor, (2K3) and check for no current - one second. If currents are detected the MMR diagnostic ‘‘Starter Fault Type II’’ is generated. (Starter Integrity test)

G. If no diagnostics are generated in the above tests, the Stop Relay (2A1- J10) is closed for 2 seconds and the Start Relay (2A1-J8) is closed to energize the start contactor (2K1). The shorting contactor (2K3) has already been energized from (F) above. The compressor motor (4M1) starts in the ‘‘Wye’’ configuration, an auxiliary contact (2K1-AUX) locks in the start contactor (2K1) coil. Additonally, 2K11 pulls in to hold the oil pump on. This is parallel to 1A7 contacts.

H. After the compressor motor has accelerated and the maximum phase current has dropped below 85 percent of the chiller nameplate RLA for 1.5 seconds, the starter transition to the ‘‘Delta’’ configuration is initiated.

J. The transition contactor (2K4) is closed through relay 2A1-J2, placing the transition resistors (2R1, 2R2, and 2R3) in parallel with the compressor motor windings.

K. The shorting contactor (2K3) is opened through the opening of relay 2A1-J4 100 msec after the closure of the transition relay 2A1-J2.

L. The run contactor (2K2) is closed through relay 2A1-J6, shorting out the transition resistors 260 milliseconds after the opening of the shorting relay 2A1-J4. This places the compressor motor in the ‘‘Delta’’ configuration and the starter module waits to look for this transition for

2.35seconds through the closure of the transition complete contacts 2K2- Aux at module 2A1-J12 input)

M. The starter module must now confirm closure of the transition complete contact (2K2-AUX) within

2.32to 2.38 seconds after the run relay (2A1-J6) is closed. Finally, the transition relay (2A1-J2) is opened de- energizing the transition contactor (2K4) and the compressor motor starting sequence is complete. An MMR diagnostic will be generated if the transition complete contacts (2K2- AUX) do not close. A diagram of this test or start sequence is shown in Figure 24.

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CDHF-SVU01C-EN

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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 SetpointCDHF/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
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