American Standard CH530 manual Restart Inhibit Free Starts, Clear Restart Inhibit

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General Information

Compressor Load Balancing Duplex chillers with CH530 control will balance the compressor load by giving each compressor the same load command. The load command will be converted to IGV position that will be the same on each compressor.

Balancing compressor load results in the best overall efficiency and with both circuits operating with nearly the same refrigerant pressures.

When both compressors are running the overall chiller load command will be split evenly between the two compressors unless limit control overrides balancing. When transitioning between one compressor operation and two- compressor operation, the load commands will be actively balanced at a rate slow enough to minimize capacity control disturbances

Restart Inhibit

The purpose of restart inhibit feature is to provide short cycling protection for the motor and starter.

The operation of the restart inhibit function is dependent upon two setpoints. The Restart Inhibit Free Starts (1-5, 3 default), and the Restart Inhibit Start to Start Timer (10-30min, 20 default). These settings are adjustable via the service tool.

Restart Inhibit Free Starts

This setting will allow a number of rapid restarts equal to its value. If the number of free starts is set to “1”, this will allow only one start within the time period set by the Start to Start Time Setting. The next start will be allowed only after the start to start timer has expired. If the number of free starts is programmed to “3”, the control will allow three starts in rapid succession, but thereafter, it would hold off on a compressor start until the Start to Start timer expired.

Restart Inhibit Start to Start Time Setting

This setting defines the shortest chiller cycle period possible after the free starts have been used. If the number of free starts is programmed to “1”, and the Start to Start Time Setting is programmed to 20 minutes, then the compressor will be allowed one start every 20 minutes. The start-to-start time is the time from when the motor was commanded to energize to when the next command to enter prestart is given.

Clear Restart Inhibit

A Clear Restart Inhibit “button” is provided within Settings; Manual Override on the DynaView display. This provides a way for an operator to allow a compressor start when there is a currently active Restart Inhibit that is prohibiting such a start. The “button” press will have no other function than to remove the restart inhibit if there is one active. It does not change the count of any internal restart inhibit timers or accumulators.

The restart inhibit function, setpoints and clear features exist for each compressor and operate independently of other compressors on that chiller.

During the time the start is inhibited due to the start-to-start timer, the DynaView shall display the mode ‘Restart Inhibit’ and the also display the time remaining in the restart inhibit.

A “Restart Inhibit Invoked” warning diagnostic will exist when the attempted restart of a compressor is inhibited.

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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
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