Liebert 610 Battery Charging Circuit, Operation After Discharge, Operation After End-of-Discharge

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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 0.5% RMS to preserve battery life during long- term float charging while the UPS system is operating on utility source power.

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 module battery disconnect (MBD) circuit breaker is used to isolate the UPS module from the bat- tery 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 adjustable to between 1 and 25% of the full load maximum discharge current. An external dry contact closure (field supplied) activates a reduced second level of the battery charge current limiting circuit for use with 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 automatic battery equalizing charge circuit increases the rectifier/charger output voltage to charge the battery 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 individual cells that are at a low state of charge, per the battery manufacturer's specification and recommendations.

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 Reliability Designed for SuccessOther Factors to Consider Safety Precautions Modes of Operation Operator Controls Options Battery Load Testing Customer Alarm InterfaceTemperature-Compensated Charging Automatic RestartBattery Plant General Component DescriptionsUPS Module Detailed Component Descriptions Controls HardwareSoftware Operation Input Power FactorRectifier/Charger Input Circuit BreakerBattery Charge Current Limiting Battery Charging CircuitBattery Disconnect Battery Equalize Charge CircuitInverter Non-Linear Load CharacteristicsUnbalanced Load Characteristics Output Regulation and Overload PerformanceBypass Circuit Breaker Static Switch Backfeed ProtectionStatic Bypass Pulsed Parallel OperationTransfer and Retransfer Conditions Three Breaker Maintenance Bypass Switchboard Features Display Screen and Operator ControlsOperator controls, typical system 100kVA 500kVA 1000kVA Description FunctionSeries 610 UPS operator control panel Description FunctionMenu Tree Navigation Menu treeMaster Menu Screen Master menu screenOperation Monitor/Mimic Display Screen Input Metering DisplaysOutput Metering Displays Status/Alarm Message Areas Item 7 Alarm MessagesItem 6 Status Messages Monitor/Mimic display example Utility fail Walk-In Display Screen Walk-in display screenStatus Reports Screens Status reports screenPresent Status Event HistoryHistory Status History status report screenBattery Cycle Monitor System StatusBattery cycle monitoring summary screen System Configuration Screens System configuration screensMaximum Auto-Retransfer Attempts Maximum auto-retransfer attempts screenDate Date screenTime Time screenAuto Dial Auto dial screenLanguage Selection System OptionsContinuous Duty Static Switch Optional Remote Monitor Alarm messagesAdditional alarm messages Standard Remote Monitor Indications ChannelBattery Discharging Alarm Limit Settings ScreenOverload Alarm Low BatteryBattery Rating Battery Shutdown 60 MinutesBattery Rating 100% Temperature Limit Setting OptionalLoad Transfer Procedures Screen Load transfer procedure screenStart-Up Procedures Screen Refer to 3.4.1 Start-Up Procedure for more detailsShutdown Procedures Screen Battery Time ScreenBattery time screen 15-minute discharge Upper Limit Actual Lower Limit Elapsed Time MinutesMeter Calibration Screen Status Reports ScreensBattery Equalize Screen Battery equalize screenAlarm and Status Messages Status Messages Alarm and status message screenAlarm Messages Abbreviations used in alarm messagesAlarm messages and corrective actions AC InputUPS System UPS System CoolingAlarm messages-summary Alarm Message Special FunctionsCommunication Interfaces Worldwide ReportingAuto-Dial Site Reporting SiteScan or Snmp Local Reporting to a TerminalLocal Reporting to a Monitor Requesting InformationSeparate / Simultaneous Outputs Series 610 terminal commandsRemote Monitor Panel Keys FunctionLoad on Bypass Circuit breaker abbreviationsAbbreviation Circuit Breaker OK to Transfer Load on bypass UPS availableLoad on UPS bypass available Momentary overload through pulse-parallel static switch Momentary OverloadsInput Power Failure-Load on Battery Input power fail-load on batteryOff Battery Load on UPS-battery not availableRefer to 3.4.4 Shutdown Procedures Emergency Module OffRemote Emergency Power Off Emergency power offRefer to 3.3.9 Maintenance Bypass Module ShutdownLoad on maintenance bypass two breakers Load on maintenance bypass three breakers Manual Procedures Start-Up ProcedureStart-Up Procedure Set the Static Switch Disconnect or to OFF open Start-up procedures Start-Up Procedure Load Transfer Procedures Load transfer procedures screenMaintenance Bypass Load Transfers Shutdown Procedures Module Shutdown Procedure Shutdown ProceduresRemote Emergency Power Off Repo Local Emergency Modules Off LemoBattery Exercise Procedures Battery exercise control screen above and results below1000% Automatic OperationsOverloads Without Transfer 150%Automatic Transfers to Bypass Overload Condition Automatic Retransfers to UPSAutomatic Transfers to Bypass UPS System Faults Automatic Restart Optional Enabling Automatic RestartSequence of Operation Maintenance Professional Start-Up Liebert Global ServicesMaintenance Agreements The Signature Program TrainingRoutine Maintenance Record LogAir Filters Limited Life Components Battery Maintenance Battery Safety PrecautionsAvertissement Matching Battery Cabinets Optional Number of Cells Battery Voltage VDC Nominal FloatBattery retorque values Battery voltage recordRack-Mounted Batteries Torque specifications unless otherwise labeled Detection of TroubleTorque Requirements Corrective Actions Reporting a ProblemUpstream Feeder Circuit Breaker Setting Inspections Recommended Test EquipmentPower factor pf KVA RatingKVA Specifications applicable to environment Environmental ConditionsAdjustments Battery OperationElectrical Specifications Page Locations Technical Support/ServiceCompany Behind the Products United States
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