Liebert 1000kVA manual Battery Charging Circuit, Operation After Discharge, Battery Disconnect

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Theory of Operation

2.2.3Battery Charging Circuit

The UPS module charging circuit is capable of recharging the battery plant to 95% of full capacity within 10 times the discharge time. Recharging the last 5% takes longer because of characteristics inherent in the battery. DC ripple voltage is limited to less than 0.5% RMS to preserve battery life during long-term float charging while the UPS system is operating on utility source power.

Multiple UPS module rectifier/chargers can share a common battery plant, if that configuration is preferred for your application.

Operation After Discharge

When commercial power is interrupted, the battery continues to supply DC power to the inverter without interruption to the critical load. If the AC source power is restored before the battery has fully discharged, the rectifier automatically restarts and resumes carrying the inverter and battery recharge load requirements.

Operation After End-of-Discharge

The battery time screen displayed on the control panel enables you to estimate when battery shut- down will occur. If the battery plant discharges to the shutdown point during an outage, the UPS automatically disconnects the load, the AC input and the battery. After AC input power is restored, the rectifier can be manually restarted by the user.

Battery Disconnect

The external module battery disconnect (MBD) circuit breaker is used to isolate the UPS module from the battery during maintenance and to automatically disconnect the battery from the inverter at the end of battery discharge. The MBD circuit breaker can be opened or tripped automatically, from the control panel or manually. It must be closed manually.

Battery Charge Current Limiting

The battery recharge current, after a battery discharge, is limited to between 1 and 25% (adjustable) of the full load discharge current. An additional (optional) charge-limiting circuit can be activated by external dry contact closure (field supplied) for use when operating on a back-up generator. These two levels of control regulate the amount of current that flows from the power source to the battery while the battery is recharging.

The battery charge current limit is factory-set at 10% for normal operation and at 1% for alternate power source recharge operation.

Battery Equalize Charge Circuit

The battery equalize charge feature can be manually initiated or it can be programmed to operate automatically. Either can be selected from the battery equalize screen displayed on the control panel.

The battery equalizing charge circuit increases the rectifier/charger output voltage to charge the bat- tery any time there is a power outage of 30 seconds or longer. The equalizing voltage is slightly higher than the float voltage. Equalize charging is primarily used in flooded battery systems to boost individ- ual cells that are at a low state of charge, per the battery manufacturer's specification and recommen- dations.

NOTE

Do not use equalize charging with valve-regulated lead-acid batteries.

Consult the battery manufacturer’s manual, available on the manufacturer’s Web site, for specific information about equalize charging.

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Contents Series 610 UPS Battery Cabinet Precautions Table of Contents Maintenance SpecificationsFigures Tables Important Safety Instructions System Description Multi-Module UPS, 100-500kVAMulti-Module UPS, 500-750kVA Designed for Success ReliabilityTypes of System Control Cabinets SCCs Safety Precautions Input Power FailureModes of Operation Other Factors to ConsiderOperator Controls 1989-2003 Battery OptionsBattery Racks or Cabinets Module Battery DisconnectThree Breaker Maintenance Bypass Two Breaker Maintenance BypassGeneral Component Descriptions System Control CabinetBattery Plant UPS ModuleSoftware Detailed Component DescriptionsControls Hardware Input Power Factor Rectifier/ChargerOperation Input Circuit BreakerBattery Charging Circuit Battery DisconnectBattery Charge Current Limiting Battery Equalize Charge CircuitNon-Linear Load Characteristics Unbalanced Load CharacteristicsInverter Output Regulation and Overload PerformanceShorted SCR Monitoring Static BypassFuse Protection Load Transfers Static Switch IsolationPulsed Parallel Operation Transfer and Retransfer Conditions Redundant Mode Retransfer InhibitedFeatures Display Screen and Operator ControlsDescription Function 500kVA1000kVA Operation Description Location Function Refer to 3.4.5 Shutdown ProceduresNumbers are used as keys to data in , below Switches behind SCC control panel door Menu Tree Navigation Menu treeModule Master Menu Master Menu ScreenSCC Master Menu Operation Output Metering Displays SCC Monitor/Mimic Display ScreenInput Metering Displays Status/Alarm Message Areas Item 7 Alarm MessagesItem 5 Module Status Messages Item 6 System Status MessagesModule Monitor/Mimic Display Screen Module Monitor/Mimic display screenAlarm Messages Item 5 Alarm MessagesSCC Display Module DisplayMonitor/Mimic display example Utility fail KVA / 217 kW 325A 325A 325A MOD On Line OFF Line SUM ALM B-C C-A 0V 0V Not OK to Transfer Static Switch Connected Walk-In Display Screen Walk-in display screen during start-upStatus Reports Screens Present StatusModule Status Report Event HistorySCC Status Report History Status History status report screensAlarm conditions that freeze history data gathering Alarm in SCC Alarm in ModuleBattery Cycle Monitor-Module Only System StatusBattery cycle monitoring summary screen System Configuration Screens SCC system configuration screenDate Date screenTime Time screenAuto dial setting screen Auto DialModem Baud Rate Maximum Auto-Retransfer AttemptsSystem Current Rating Language SelectionSystem Options Retransfer AttemptsBattery test screen-MMU only Continuous Duty Static Switch OptionalRemote Monitor SCC and module remote monitor indicationsAlarm Limit Settings Screen Module alarm limit settings screenBattery Float Voltage Temperature Limit Setting OptionalLoad Transfer Procedures Screen Refer to 3.4.3 Load Transfer Procedures for more detailsStart-Up Procedures Screen Refer to 3.4.1 SCC Start-Up Procedure for more detailsShutdown Procedures Screen Module start- up procedures screensSCC shutdown procedures screen Battery Time Screen Module Only Battery time screen 15 minute dischargeUpper Limit Actual Lower Limit Elapsed Time MinutesOperation Meter Calibration Screen Meter calibration screenBattery Equalize Screen Battery equalize screenAlarm and Status Messages Module Status Messages System Status MessagesAbbreviation Definition Abbreviations used in alarm messagesLoad Block Messages Alarm messages meaning and corrective action Manual Reset Static SwitchBypass Phase Control PowerReverse Power Inverter FaultTransfer Module N OffBattery Overtemp OvertemperatureTimeout New AlarmSpecial Functions Alarm messages summaryAlarm Message Communication Interfaces Worldwide ReportingAuto-Dial Requesting InformationSite Reporting SiteScan or Snmp Local Reporting to a TerminalLocal Reporting to a Monitor Separate / Simultaneous Outputs Series 610 terminal commandsRemote Monitor Panel Circuit breaker abbreviations Abbreviation Circuit Breaker Load on Bypass OK to TransferLoad on bypass, UPS available Momentary overload, pulsed static bypass switch Momentary OverloadsInput Power Failure-Load on Battery Input power fail-load on batteryOne Module Off-Line One module off-line, load on UPSOff Battery Load on UPS-battery not availableRefer to 3.4.5 Shutdown Procedures Emergency Modules OffRemote Emergency Power Off Emergency power offRefer to 3.3.10 Maintenance Bypass System ShutdownLoad on maintenance bypass, two breakers Refer to 3.5 Automatic Operations for more details Manual ProceduresSCC Start-Up Procedure Operation Operation SCC start-up procedures screen UPS Module Start-Up Module start-up procedures screen Operation Load Transfer Procedures Manual Transfer Instructions UPS LeadIf the load is on the UPS System Bypass Maintenance Bypass Load TransfersIf the load is on Maintenance Bypass Shutdown Procedures System Shutdown Procedure Module Shutdown Procedure Local Emergency Modules Off Lemo Remote Emergency Power Off RepoAutomatic Operations Overloads Without Transfer Automatic Transfers to Bypass1000% 150%Automatic Emergency Modules Off Automatic Retransfers to UPSAutomatic Module Off-Line Maintenance Liebert Global Services Maintenance Agreements The Signature ProgramProfessional Start-Up TrainingAir Filters Routine MaintenanceRecord Log Limited Life Components Battery Maintenance Battery Safety PrecautionsAvertissement Matching Battery Cabinets Optional Number of Cells Battery Voltage VDC Nominal FloatRack-Mounted Batteries Battery retorque valuesBattery voltage record Torque Requirements Torque specifications unless otherwise labeledDetection of Trouble Reporting a Problem Upstream Feeder Circuit Breaker Setting InspectionsCorrective Actions Recommended Test EquipmentKVA Power factor pf KVARating Specifications applicable to environment Environmental ConditionsAdjustments Battery OperationElectrical Specifications Specifications 112 Page Technical Support/Service Company Behind the ProductsLocations United States