Trane CVHE-SVU01E-ENX39640712050 manual Evaporator Variable Flow Compensation, Condenser Limit

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Machine Protection

and Adaptive

Control

Evaporator Variable Flow Compensation

This option includes transducers for the differential evaporator and condenser water pressures (psid). Flow switches or some other means to prove flow are still required and must be field connected.

The following data will be shown at the DynaView and TechView displays and at Tracer Summit.

•Evaporator and condenser differential water pressures (psid)

•Evaporator and condenser gpm

•Evaporator tons

How It Works

The Tracer chiller controller uses a patented, variable, water-flow compensation algorithm to maintain stable, precise capacity control. Variable flow compensation is a new optional control feature for CTV chillers.

It will automatically adjust capacity control to:

•Maintain control stability at low flow.

•Reject variable-flow disturbance.

If the water-pressure transducer fails and the flow switch continues to prove flow, water-flow compensation will be disabled and the design delta T will be used.

For applications designed to operate with variable-primary (VPF) water- flow, variable flow compensation allows the chiller to respond quickly to accelerating or decelerating water. By automatically adjusting the control gain, large changes in the water-flow rate can be tolerated.

For details, refer to CTV-PRC007-EN.

CVHE-SVU01E-EN

Condenser Limit

Condenser pressure is continuously monitored to provide a limit function that prevents High Pressure Cutout (HPC) trips. This protection is called Condenser Refrigerant Pressure Limit, or High Pressure Limit. A fully loaded compressor, operating at high Evaporator Leaving Water Temperature (ELWT) and high condenser temperatures causes high condenser pressures. The purpose of this limit is to avoid High Pressure Cutout (HPC) trips by allowing the Chiller to continue to run at a lower load instead of tripping off via HPC.

The Condenser Limit will be based from a pressure conversion from the Condenser Refrigerant Temperature sensor, unless there is a Condenser Refrigerant Pressure sensor installed (CDRP option). If the Condenser Refrigerant Pressure Sensor is installed, then the limit will be based from the Pressure sensor.

When limited by this action, “Condenser Pressure Limit” will be displayed as a sub-operating mode. The Condenser Limit Setpoint is factory set (93 percent of HPC), however can be altered via the service tool.

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Contents Operation Maintenance Read these carefully Contents Unit Nameplate General InformationLiterature change About this manualC0000000K01G14C10W1A03B1 CVHF091NAL00ACU2758W7E8TBControl Optional Packages Commonly Used AcronymsCvhf OverviewGeneral Information General Information Cvhf Compressor Cooling CycleCVHE, Cvhg pressure enthalpy curve Cvhf pressure enthalpy curve DynaView Human Interface TechView Chiller Service ToolCVHE, CVHF, and Cvhg sequence of operation running General Information Oil and Refrigeration Pump Surface TemperaturesOil refrigerant pump 20 100 percent RLA Base Loading Control AlgorithmGeneral Information Ice Machine Control Free Cooling Cycle Free Cooling Frcl Hot Gas Bypass Hot Water control Auxiliary Condensers Heat Recovery CycleUnit 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 Minsec System ResetReference Main Screen Diagnostic Screen Back button provides navigation back to the chiller screen Operator Interface Condenser Report Items Units Reports Evaporator Report items UnitsPurge Report Items Units Compressor Report Items UnitsMotor Report Items Units RPMPPM Historic Diagnostics LogAshrae Chiller Log Units RLAChilled Water Setpoint Chiller Feature SettingsMode Overrides Description Units Default Monitor ValueDescription Units Default Display SettingsPurge Operator Interface Operator Interface Operator Interface Operator Interface Operator Interface Binding Interprocessor CommunicationInter Processor Communications IPC3 IPC3 Definitions Bus ManagementControl System Components Control panel components layout and approximate dimensionsControl System Components Control Panel Devices Opst Machine Shutdown Manual Reset MMRHead Relief Request Output Compressor Running RelayExop Refrigerant Monitor Input 1A17Cdrp Condenser Refrigerant Pressure Output Frcl Free Cooling OptionHgbp Hot Gas Bypass Option Trmm TRM4 Tracer Comm 4 interfaceTemperature based Condenser Pressure OutputPressure based Refrigerant Differential Pressure Indication Output Gbas Generic Building Automation System GbasPercent RLA Output Wpsr WFC Water Pressure Sensing Option Module CharacteristicsExternal Chilled Water Setpoint Ecws External Current Limit SetpointComm + 1A8, 1A9, 1A11, 1A12 Quad Relay Output Status1A13, 1A18, 1A19, 1A20 Dual Binary input module 1A14 Communication interface ModuleRecommended Length to Run external Output signals 1A15, 1A16, 1A17, 1A21 Dual Analog Input/output ModuleAnalog Input Unit mounted devices 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 AFD 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 CutoutMain Processor Software Revision 6.0 and higher Low Refrigerant Temperature CutoutCutout strategy Condenser Limit Evaporator Variable Flow CompensationClear Restart Inhibit Restart Inhibit Start to Start Time SettingRestart Inhibit Restart Inhibit Free StartsHigh Vacuum Lockout Oil Temperature Control Return Water Controls Chilled Water Reset CWROutdoor Air Temperature Maximum ResetEquation Values for start reset typesDegrees of Reset Constant ReturnOutdoor 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 Seasonal Unit Start-Up Before changeover to heating modeLive Electrical Components Toxic HazardsSeasonal Unit Shutdown Unit Shutdown ProceduresUnit Shutdown Oil Pump Heater OperationRecord Keeping Forms Periodic MaintenanceDaily Maintenance and Checks Moisture ContaminationEvery 3 Months Weekly MaintenanceNormal Chiller Operating Characteristics Hazardous Voltage w/ CapacitorsAnnual Maintenance Off-Season MaintenanceCompressor Oil Change on Oil MaintenanceOil Change Procedure Heater DamageReplacing Oil Filter Oil Filter ReplacementLubrication MaintenanceOil Supply System Problems Other Maintenance RequirementsFront View with Refrigerant Pump Do not Leave Grease Fittings InstalledRefrigerant Charge Contains RefrigerantProper Water Treatment Recovery and Recycle ConnectionsLeak Testing Cleaning the CondenserCleaning the Evaporator Control Settings AdjustmentsUnit Corrosion Damage Unit Preparation Purge SystemHazardous Voltage w/ Capacitors 100 101 102 103 104 105 106 107 108 109 110 111 Trane
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