American Standard CH530 manual Current Limit Protection, Reverse Rotation Protection

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Machine Protection

and Adaptive

Control

Current Limit Protection

Current Limit Protections exist to avoid motor current overload and damage to the compressor motor during starting and running.

Compressor motor current is continuously monitored and current is controlled via a limit function that to prevent running into over current diagnostic trips.

The current limit control logic attempts to prevent the motor from shutting down on a diagnostic trip by limiting compressor current draw relative to an adjustable current limit DynaView™ Current Limit Setpoint. This setpoint can also be lowered to provide electrical demand limiting on the unit as required. This could also be set to allow the Chiller to continue to run at a lower load to avoid tripping off via a diagnostic.

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The Current Limit function uses a PID algorithm (Similar to the Leaving Water Temperature control) that allows the chiller to run at the Current Limit Setpoint. At machine startup, or with any setpoint change the new current limit setpoint reached after the is filtered setpoint time elapses. The minimum current limit setpoint is default set to 40 percent RLA (20-100 percent). The filtering time is default set to 10 minutes (0-120 minutes), however these can be altered via the service tool. This filtered setpoint allows for stable control if the Current Limit setpoint is adjusted during a run.

The Current Limit Setpoint (CLS) can be changed from: Front Panel, External Analog input (with GBAS (external) option), or Tracer (Tracer option). However, If present Tracer current setpoint has the highest priority, unless disabled in the DynaView™ Setpoint source override menu. The External CLS has second priority, and will be used if Tracer is disabled or not installed. The Front Panel Setpoint has the lowest priority, and will be used if Tracer and the External CLS are both disabled.

Phase Loss Protection

Loss of phase detection protects the chiller motor from damage due to a single-phasing condition. The controls will shut down the chiller if any of the three phase currents feeding the motor are lost. The shutdown will result in a latching diagnostic indicating the failure. The motor is protected from over-current during a single-phase condition by the Current Overload Protection feature. Phase Loss Protection provides redundant protection and a diagnostic that more accurately describes the fault.

Reverse Rotation Protection

This function protects the compressor from being driven in the reverse direction. Incorrect phase rotation detection results in a manually resettable diagnostic. Phase Reversal protection is default to Enable, however can be disabled via the service tool.

CDHF-SVU01C-EN

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Contents X39640670030CDHF-SVU01C-EN Read these carefully Contents About this manual General InformationLiterature change 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 InterfaceSoftware States Figure Power Up DiagramSoftware Operation Overview Diagram 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 Free Starts Restart Inhibit Start to Start Time SettingRestart Inhibit 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 Main Screen Chiller Operating ModeCircuit Operating Mode Main Screen Data Fields TableDiagnostic Screen Back button provides navigation back to the chiller screen Operator Interface Report Menu ReportsReport name System Condenser Report name System EvaporatorReport name Circuit Evaporator Report name Circuit CondenserHistoric Diagnostics Log Report name System Ashrae Chiller LogSetting Tab screens provides a user Header ScreenFeature Settings ChillerDisplay Settings System Mode OverridesCircuit Mode Overrides PurgeOperator Interface Operator Interface Operator Interface Operator Interface Operator Interface IPC3 Definitions Bus Management Interprocessor CommunicationInter Processor Communications IPC3 BindingControl System Components Control panel components layoutControl System Components Control Panel Devices Maximum Capacity Relay Machine Shutdown Manual Reset MMRHead Relief Request Output Compressor Running RelayRefrigerant Monitor Input 1A17 ExopEpro Enhanced Protection Trmm TRM4 Tracer Comm 4 interfaceCdrp Condenser Refrigerant Pressure Output Condenser Pressure Output Temperature basedCdrp Refrigerant Pressure Output Option 1A15 Pressure basedRefrigerant Differential Pressure Indication Output Gbas Generic Building Automation System Percent RLA OutputExternal Current Limit Setpoint Module CharacteristicsExternal Chilled Water Setpoint Ecws 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 Maximum Reset Controls Chilled Water Reset CWROutdoor Air Temperature Return WaterConstant Return Values for start reset typesDegrees of Reset 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 Seasonal Unit Start-Up Live Electrical ComponentsToxic Hazards ModeOil Pump Heater Operation Unit Shutdown ProceduresUnit Shutdown Seasonal Unit ShutdownMoisture Contamination Periodic MaintenanceDaily Maintenance and Checks Record Keeping FormsHazardous Voltage w/Capacitors Weekly MaintenanceNormal Chiller Operating Characteristics Every 3 MonthsOff-Season Maintenance Annual MaintenanceHeater Damage Oil MaintenanceOil Change Procedure Compressor Oil ChangeOil Filter Replacement Replacing Oil FilterOther Maintenance Requirements MaintenanceOil Supply System Problems Hazardous Voltage w/ CapacitorsRotary valve in drain position Front View with Refrigerant PumpContains Refrigerant Refrigerant ChargeCleaning the Condenser Recovery and Recycle ConnectionsLeak Testing 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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