Liebert 30-130kVA manual Operation After End-of-discharge, Battery Disconnect, Inverter

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Theory of Operation

Operation After End-of-discharge

The battery time screen displayed on the control panel enables you to estimate when battery shut- down will occur. You will have enough time to energize an alternate AC power source or to initiate an orderly shutdown of the critical load. 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 Operator.

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 must be closed manually unless you have the optional motorized battery breaker. (See 3.3.8 - Auto Restart).

Battery Charge Current Limiting

The battery recharge current, after a battery discharge, is limited to between 1 and 25% (adjustable) of the full load maximum discharge current stated in AMPS. This regulates 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 one-half of maximum or 12.5% 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 anytime there is a power outage of 30 seconds or longer. The equalizing voltage is slightly higher than the float voltage. This helps all the batteries in a string to reach a uniform state of charge.

NOTE

The manufacturers of the valve-regulated batteries supplied with Liebert’s standard battery cabinets recommend that when first installed the batteries be equalize charged. After that initial equalize charge, they recommend no further equalize charging for their batteries. Other manufacturers may have different recommendations for their products. Consult the battery manufacturer’s manual for specific information about equalize charging.

2.2.4Inverter

The inverter is a solid state device that converts the DC output of the rectifier/charger or the battery to AC power.

Operation

The inverter converts DC power from either the battery or the rectifier/charger into three pulse- width-modulated/six-step waveforms. These waveforms are filtered into low-distortion sine wave power. The inverter is controlled by a Digital Signal Processor (DSP). This DSP controls the precise synchronization, amplitude, and frequency of the output voltage.

In addition to the inverter efficiently supplying a regulated AC output from a DC source, the inverter output provides isolation between the critical load bus and the commercial source power. The inverter is configured to handle most critical load inrush surges. It maintains output voltage Total Harmonic Distortion (THD) within specifications even when handling nonlinear computer loads.

Output Regulation and Overload Performance

The inverter is capable of sustaining full output voltage (±1% of the nominal voltage) for up to 150% overload at the output for as long as 60 seconds without reducing the output voltage. It can also han- dle at least 125% of the rated current for up to 10 minutes. If an overload exceeds the system capacity and a bypass source is available, the critical load is transferred to the bypass source and the inverter is disconnected from the load.

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Contents Npower UPS Page Table of Contents Communication Interfaces MaintenanceFigures Page Tables Page Important Safety Instructions Overview of Manual System Description Versatility Safety PrecautionsFactory Backup and Service Assistance ReliabilityRecharge Input Power FailureModes Of Operation Normal Load On UPSCHG Mimic DisplaySYS. Status Options Operator ControlsGeneral Component Description Battery SystemUPS Module Controls Hardware Detailed Component DescriptionsFirmware Operation Input Power FactorBattery Charging Circuit Rectifier/ChargerOperation After End-of-discharge Battery DisconnectBattery Charge Current Limiting Battery Equalize Charge CircuitStatic Switch Backfeed Protection Nonlinear Load CharacteristicsUnbalanced Load Characteristics Static Bypass SwitchTransfer and Retransfer Conditions Operation Operation Navigation Buttons Operator Control PanelRotary switch Rotary SwitchPrev Cancel Save & Exit ConfigurationUser Settings Security Access and PasswordsMenu Tree Display Screens and ProceduresSecondary Screens Primary ScreensMimic Display Screen Main Menu ScreenDischg FaultsFaults / Alarms RectSYS. Status Mimic DisplayTemps DEG C Inlet AIR Outlet AIR Heat Sinks DC BUS / Battery StatusInput Status FreqBypass Input Status Freq .9 HZ 213 214 Phase DiffOutput Load Status EXI T Active Faults and AlarmsFaults and Alarms User ShutdownNext System RatingsSecond Scenario Manual StartupAuto Startup Skip Abort Input Modify Current Limit Target and Ramp ValuesModify DC BUS SET Point Target and Ramp Values ServExternal maintenance bypass switch, dual-input UPS SIB External Maintenance BypassExternal maintenance bypass switch, single-input UPS External Maintenance Bypass Switch Configurations Multiple Battery CabinetsShutdown User ShutdownStatus Reports Status ReportsSystem Status History LOG Clear History Logs Clear Event LOGTotal Event LOGEvent Log Output History LOG02 / 10 OUT-V IN-V Load FreqInput of / UF SBS Line Trap SBS LoadExit Configuration ScreensPrev DC BUS VoltsInput Frequency Output FrequencyCurrent Date System SettingsCancel Save & Exit System SettingsTime Next PREV. Cancel Save & ExitCurrent Time Order NumberOutput Transformer Bypass WIND. no Enter PasswordSingle / Dual Input DualOptions 10% Passive Filter SettingsOptions Active Filter LBS Generator Auto RestartPrev Exit Pulse Rectifier Battery GND Fault Green MachineAlternate Power Pole FAN no Line Drop CompensationAuto Dial Communication OptionsNext Exit Auto Dial YES Auto Dial OUT Pager Pager Support ConfigurationPager Enabled Pager Number Pager PIN Modem Health CheckPREV. Cancel Next PREV. Cancel Factory Settings 10 % Passive Filter SettingsNext Cancel Freeze Alarm MaskLatching DialSave & Exit Cancel Alarm / Fault NameAlarm / Fault Name Battery Fuse Fail Alarm / Fault Name F EAuto Dial Customer Alarm InterfaceProgrammable Output Relay Board # Customer Alarm InterfaceRemote LED Board # STD SET User Defined Relay AssignmentsSTD SET UP Down ADD Remove Clear Exit Prog Relay #Manual Transfer Navigating ProtocolBattery Test Battery ManagementAuto Test MIN MAX Weeks Battery CycleBattery Duration Battery EqualizerStop Start Enabled DisabledAuto ManualEqualize Time Period Battery Temp Compensation ChargeTemperature Battery Temperature Compensation ChargeBattery Cycle Monitor Battery Temp CompensationSummary Clear BCM Battery Cycle MonitorClear Summary YES / no Summary Seconds Discharge CyclesTime Down BATT. EOD Lower SET Point BATT. EOD Upper SET Point Battery Time Low WarningBATT. Time LOW Warning Battery SupplementAuto Restart Auto Restart Trigger Condition Alarm NotificationsSystem Status Monitoring System StatusSign OFF Date 10/30/02 System StatusSign OFF Date 10/30/01 Next Prev Save & ExitAccumulated # of Brown Outs Accumulated Backup HoursAccumulated Operating Hours on UPS Accumulated Operating Hours on BypassFaults Faults, Alarms, StatusDescription L Latching...D Dial Alarm / Fault Name F E DelayOn Battery Input Contact #1 UP DownSummary Alarms, functions, and corrective actions Alarm MessagesContact Liebert Global Service to check Excess load from the UPS and attempt to EPO Maximum heat sink temperature limit This is a summary event based on Battery is discharging. This occurs RMS input current has reached Output kVA or kW or RMS current has With the load on UPS, PhaseB output KVA Condition only causes an alarm, but should Push-button switch located on See 3.3.7 Battery Management All of the alarms before attempting to Status Communication InterfacesWorldwide Reporting 1 RS-232 Port Local Reporting TerminalAuto-Dial Dial Out Pager Requesting InformationSiteScan Remote Alarm Status PanelLoad on Bypass Setting Up External Communication DevicesOK to Transfer Momentary Overloads Input Power Failure Load on BatteryAutomatic Re-transfers to UPS Automatic OperationsOverloads Automatic Transfers to BypassAutomatic Module Off Line Maintenance Air Filters Routine MaintenanceBattery Maintenance Record LogBattery Safety Precautions Torque Requirements Battery voltage recordRecommended Test Equipment Reporting a ProblemDetecting Trouble Corrective ActionsMaintenance 101 Maintenance 102 Page Ne t
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