Sterling SCW Series installation manual Staging, Alarms, Lead-Lag Compressors, Lead-Lag Pumps

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4	Sequence Of Operation

4-1 Staging

1.The system uses a PID control algorithm to regulate the chilled water temperature. As the required control effort increases or decreases, the system compressors are infinitely unloaded or turned on/off to keep the temperature at the specified set-point.

2.Compressor anti-recycle time is two (2) minutes.

4-2 Alarms

If a fault occurs, that compressor or circuit is deactivated. The load will automatically shift to any other compressors that are currently ON-LINE, but not running. Lead/Lag rotation will continue to function. Compressors that are faulted will be removed from the rotation order.

4-3 Lead-Lag Compressors

The system automatically rotates the compressor order to generate a Lead/Lag rotation. Any time a compressor is faulted or manually taken OFF-LINE, it will be removed from the Lead/Lag rotation.

Once the fault is cleared or manually put ON-LINE, the compressor is returned to the Lead/Lag rotation at the end of the rotation order.

4-4 Lead-Lag Pumps

The system automatically rotates the pump order to generate a Lead/Lag rotation. Any time a pump is faulted or manually taken OFF-LINE, it will be removed from the Lead/Lag rotation. Once the fault is cleared or manually put ON-LINE, the pump is returned to the Lead/Lag rotation at the end of the rotation order.

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SCW Series Central Chilling Stations

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Contents SCW Series Central Chilling Stations SCW Series Central Chilling Stations Safety Considerations Wear Safety Glasses and Work GlovesTable of Contents Startup Checklists Indicator Lights and Control Switches MMIViewing and Operating Chiller Pumps Charts and Figures Introduction Necessary DocumentsStandard Features Models CoveredStandard Features on Remote Condensers Available OptionsModel Number Nomeclature Typical Two-Circuit 60-195 Ton Water Cooled Chiller Nominal water flow gpm460/3/60 Vf Typical Two-Circuit 60-195 Ton Remote Air Cooled Chiller 460/3/60Scwr Series Remote Condenser Models Unpacking and Inspection Event of Shipping DamagesIf the Shipment is Not Complete If the Shipment is Not CorrectReturns Bill of lading Packing listUncrating Your New Chiller SCW Series Central Chilling Stations Installation Location Considerations Making Electrical ConnectionsCheck Compressor Rotation Before Starting Unit Making Process Water Connections Piping ConsiderationsTo Process Making Tank Piping Connections Water Connection Sizing Considerations Galvanic Corrosion ConsiderationsWater Treatment Considerations Making Water-Cooled Condenser ConnectionsCondenser Water Installing the Remote Air-Cooled CondenserCondenser Water Out Compressor Checking Motor DirectionWater Pump Condenser Fan Alarms StagingLead-Lag Compressors Lead-Lag PumpsRefrigeration Circuit Chilled Water CircuitFreezestat Control Freezing Protection Curve Percent byFlow Switch High pressure cutout settingHigh Pressure Cutout Low Pressure CutoutControl Nozzle Control ProbeChilled Water Manifold Optional Condenser Water ManifoldSCW Series Central Chilling Stations Startup Checklists Water-Cooled SCW Series Startup ChecklistSCW Series Central Chilling Stations Water-Cooled SCW Series Startup Remote Air-Cooled SCW Series Startup Checklist SCW Series Central Chilling Stations Remote Air-Cooled SCW Series Startup Fan Set on Set off Number Psi KPa BarsDetermining Flow Rate ShutdownIndicator Lights and Control Switches MMI Graphic Panel DevicesSCW Series Central Chilling Stations Operator Interface Using the StandardOperator Interface Introduction Using the SCW Series Standard Operator Interface SCW Series Standard Control PanelViewing and Operating Chiller Pumps Viewing Active Alarms and Handling Alarm Conditions Viewing and Setting System TemperaturesSetting System Temperatures Touchscreen Interface Using the AdvancedTouchscreen Interface Introduction MMI Using the SCW Series Advanced Touchscreen Interface Viewing Compressor Status Main Menu ScreenChiller Status Screen Chiller Configuration Screen SCW Series Central Chilling Stations Compressor Run Time Display Screen Viewing Chiller Pump Status Pump Status Screen Pump Enables Screen Pump Run Time Display Screen Pumps Alarm Condition Screen Viewing and Setting System Temperatures System Status Screen Temperature Input Display Screen Condenser Maintenance LubricationRemote Air-Cooled Water-CooledEvaporator Maintenance Pump Motor SealMakeup Valve Recommended Pump Tank Spare PartsPreventive Maintenance Service SCW Series Central Chilling Stations Troubleshooting Problem Possible Cause Solution Verify proper rotation if Service Notes Index Determining Flow RateSCW Series Central Chilling Stations Service Notes Service Notes Service Notes Technical Assistance Parts Department