Sequencing Balanced Starts and Hours | American Standard CH530

General Information

Sequencing - Balanced Starts and Hours

When desired to balance the wear between the compressors. This method will extend the time between maintenance on the lead compressor. When balanced starts and hours is selected, the compressor with the fewest starts will start. If that compressor is unavailable to start due to a circuit lockout (including

restart inhibit) or a circuit diagnostic, then the other compressor will be started. The second compressor will stage on when chiller capacity exceeds the Stage on Load point for 30 seconds. When chiller capacity falls below Stage off Load point for 30 seconds, the compressor with the most hours will be shut off.

Figure 14. CDHF/G sequence of operation: equalize starts and hours

CDHF-SVU01C-EN

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American Standard CH530 manual Sequencing Balanced Starts and Hours, CDHF/G sequence of operation equalize starts and hours

Contents

X39640670030CDHF-SVU01C-EN Read these carefully Contents Unit Nameplate General InformationLiterature change About this manual General Information = 560 3 stage 935 2 stage Y = 500 3 stage 835 2 stage Control Optional Packages Commonly Used Acronyms General Duplex unit components front view Overview General Duplex unit components 2 stage compressor Compressor 1 or 2 2 Stage Cooling Cycle Pressure enthalpy curve 3 stage compressor Pressure enthalpy curve 2 stage compressor DynaView Human Interface TechView Chiller Service Tool Timeline Text Figures Power Up DiagramSoftware Operation Overview Diagram Software States Figure Staging Second Compressor On CDHE/F/G sequence of operation auto to running Satisfied Setpoint Staging Second Compressor Off CDHF/G sequence of operation lead 1/lag CDHE/F/G sequence of operation lead 2 lag Fixed Sequence Compressor 2 / Compressor CDHF/G sequence of operation equalize starts and hours Sequencing Balanced Starts and Hours CDHF/G sequence of operation combined start Simultaneous Compressor Start/ Stop Clear Restart Inhibit Restart Inhibit Start to Start Time SettingRestart Inhibit Restart Inhibit Free Starts Oil and Refrigerant Pump Surface Temperatures Oil refrigerant pump circuit 1 or 20 100 percent RLA Base Loading Control Algorithm General Information Sequence of operation ice making running to ice making Ice Machine Control Hot Water control Control Panel Devices and Unit Mounted Devices Unit Control Panel UCPUnit Control Panel UCP User-defined language support Variable water flow through the evaporator DynaView main processor Operator Interface Operator Interface How It Works Chiller Stop Prevention/Inhibit Feature Top Level Mode Description System Reset Reference Main Screen Data Fields Table Chiller Operating ModeCircuit Operating Mode Main Screen Diagnostic Screen Back button provides navigation back to the chiller screen Operator Interface Reports Report Menu Report name Circuit Condenser Report name System EvaporatorReport name Circuit Evaporator Report name System Condenser Report name System Ashrae Chiller Log Historic Diagnostics Log Header Screen Setting Tab screens provides a user Chiller Feature Settings Purge System Mode OverridesCircuit Mode Overrides Display Settings Operator Interface Operator Interface Operator Interface Operator Interface Operator Interface Binding Interprocessor CommunicationInter Processor Communications IPC3 IPC3 Definitions Bus Management Control panel components layout Control System Components Control System Components Control Panel Devices Compressor Running Relay Machine Shutdown Manual Reset MMRHead Relief Request Output Maximum Capacity Relay Exop Refrigerant Monitor Input 1A17 Cdrp Condenser Refrigerant Pressure Output Trmm TRM4 Tracer Comm 4 interfaceEpro Enhanced Protection Pressure based Temperature basedCdrp Refrigerant Pressure Output Option 1A15 Condenser Pressure Output Refrigerant Differential Pressure Indication Output Percent RLA Output Gbas Generic Building Automation System Wpsr WFC Water Pressure Sensing Option Module CharacteristicsExternal Chilled Water Setpoint Ecws External Current Limit Setpoint 1A13, 1A18, 1A19, 1A20 Dual Binary input module 1A8, 1A9, 1A11, 1A12 Quad Relay Output Status1A14 Communication interface Module 1A15, 1A16, 1A17, 1A21 Dual Analog Input/output Module Recommended Length to Run external Output signalsAnalog Input Unit mounted devices Control System Components Control System Components Electrical Sequence Control Sequence of OperationUCP and Wye-Delta Starter Control Circuits Delay time 200 msec. Opens 2K1 Control Sequence of Operation Test and start timing sequence Control Sequence Operation AFD Machine Protection Adaptive Control Momentary Power Loss MPL Protection Overload trip time versus percent RLA Current Overload Protection Current Limit Protection Phase Loss ProtectionReverse Rotation Protection SoftLoading Differential to Start or StopMinimum and Maximum Capacity Limit Evaporator Limit Leaving Water Temperature Cutout Head Relief Relay Low Refrigerant Temperature Cutout Cutout strategy Condenser Limit Restart Inhibit High Vacuum Lockout Oil Temperature Control Return Water Controls Chilled Water Reset CWROutdoor Air Temperature Maximum Reset Equation Values for start reset typesDegrees of Reset Constant Return Outdoor air temperature versus degrees of reset Reset Ratio Reset function for return CWR Reset Ratio = 50% Return CWR Unit Startup Unit Start-Up ProceduresDaily Unit Start-Up Mode Live Electrical ComponentsToxic Hazards Seasonal Unit Start-Up Seasonal Unit Shutdown Unit Shutdown ProceduresUnit Shutdown Oil Pump Heater Operation Record Keeping Forms Periodic MaintenanceDaily Maintenance and Checks Moisture Contamination Every 3 Months Weekly MaintenanceNormal Chiller Operating Characteristics Hazardous Voltage w/Capacitors Annual Maintenance Off-Season Maintenance Compressor Oil Change Oil MaintenanceOil Change Procedure Heater Damage Replacing Oil Filter Oil Filter Replacement Hazardous Voltage w/ Capacitors MaintenanceOil Supply System Problems Other Maintenance Requirements Front View with Refrigerant Pump Rotary valve in drain position Refrigerant Charge Contains Refrigerant Proper Water Treatment Recovery and Recycle ConnectionsLeak Testing Cleaning the Condenser Control Settings Adjustments Cleaning the EvaporatorUnit Corrosion Damage Unit Preparation Purge System 103 104 105 106 107 108 109 110 111 112 113 114 115 Trane