Emerson 250-400kVA manual Reporting a Problem, Corrective Actions

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Maintenance

3.6Reporting a Problem

If a problem occurs within the UPS, review all alarm messages along with other pertinent data. Con- tact Liebert Services at 1-800-LIEBERT to report a problem or to request assistance.

3.7Corrective Actions

For each alarm message on the Display Screen, you can find the recommended corrective action in Table 7.

3.8Upstream Feeder Circuit Breaker Setting Inspections

During normal UPS operations, short-term overload current demand from the bypass source may reach 10 times the UPS output current rating. This overload current demand may be caused by the magnetizing inrush current of one or more downstream transformers (i.e., power distribution units) or faults on downstream branch circuits. The instantaneous trip point(s) of the upstream bypass feeder breaker(s) must be set to support these temporary overloads. The magnitude of short-term overload bypass current demand is typically six to eight times the UPS current rating, but must be determined by analysis on a per-site basis. This analysis, generally known as an End-to-End Fault Coordination Study, must be done by a registered professional engineer experienced in this activity and familiar with local codes and related requirements.

Liebert strongly recommends periodic inspections of the bypass feeder breaker instantaneous trip set- tings, as well as the module input (rectifier) feeder breaker trip settings, to ensure that they are cor- rect. For a variety of reasons, although typically during circuit breaker maintenance procedures by others, trip settings have been known to be inadvertently left improperly set. Correct trip setting of these circuit breakers is most important to achieving high-availability from your Liebert UPS system. For further information regarding proper trip settings for your feeder breakers, call 1-800-LIEBERT.

NOTE

The instantaneous trip setting of the breaker feeding the UPS bypass input should be high enough to accommodate short-duration overloads. The bypass static switch power path inside the UPS can draw up to 10 times the system’s rated current for up to three cycles.

NOTE

While Liebert can provide typical guidelines, the responsibility for the proper breaker trip settings outside the Liebert-manufactured UPS equipment resides with the owner. Contact Liebert Services at 1-800-LIEBERT for further details.

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Contents Liebert NXL Battery Cabinet Precautions Contacting Liebert for SupportTable of Contents Specifications Figures Page Important Safety Instructions Modes of Operation Normal ModeGeneral Description Bypass Mode Battery ModeMaintenance Bypass OptionsIntroduction Features Main component locationsMimic display Monitor/mimic display example Normal power flow Monitor/mimic display example Utility failMonitor/mimic display example Load on bypass, UPS On Touchscreen Navigation Main Display Screen Menu treeConfigurations Menu Rating Rating ParametersUser Settings System Settings parametersAdjustable Setpoints Adjustable setpoints parametersCell Count Adjustment Startup Menu Event ManagementStatus Reports Menu Shutdown Menu Shutdown menuTransfer/retransfer commands Transfer MenuBattery Management Menu Time remaining displayDisplay summary see Figure Reset MeteringHelp SilenceOK to Transfer Load on bypass, UPS availableInput Power Failure-Load on Battery Input power fail, load on batteryOff Battery Emergency Module OffManual Procedures Remote Emergency Power OffStartup Procedure Startup commands Load Transfer Procedures Transfer ProcedureRe-Transfer Procedure Maintenance Bypass Load TransfersMaintenance Bypass Load Transfers-If Load is on UPS Bypass Shutdown Procedures UPS Shutdown ProcedureSystem Shutdown Procedure Automatic OperationsAutomatic Transfers to Bypass Overload Condition Current-versus-time curves of overload capacityAutomatic Transfers to Bypass, UPS System Faults Automatic Retransfers to UPSSafety Precautions Liebert Services Routine MaintenanceRecord Log Air FiltersBattery Maintenance UPS component service lifeLimited Life Components Component Expected Life ReplaceBattery Safety Precautions Battery retorque values Matching Battery Cabinets-OptionalBattery voltage, nominal and float Torque specifications, unless otherwise labeled Detecting TroubleRack-Mounted Batteries Torque RequirementsCorrective Actions Reporting a ProblemUpstream Feeder Circuit Breaker Setting Inspections Battery Operation Environmental specificationsParameter Specification Environmental ConditionsElectrical specifications Battery & DC ParametersLiebert NXL Model Size 250 Input ParametersPhysical Parameters & Standards, in mm Liebert NXL Model SizeSystem Parameter Specifications Liebert NXL alarm and status messages Event Message Event Definition Recommended ActionObserve the One-Line Display. If the input line is Observe the One-Line Display. To identify which Do not Attempt to Close CB3 Until Reset Displayed on the Module Output Meter. If UPS controls monitor the DC Bus positive Resolve the issue that precipitated the EPO Check the One-Line Display for system status UPS, to transfer back to Inverter If this alarm occurs on an operational unit, it Attempt to manually close the disconnect by Module Output Meter. If the load is less than Output Power Factor. If the displayed power factor Until a service visit has been made and action taken When manual transfers are enabled Under normal conditions, no user action is required Observe the One-Line Display and the Active Event If the command to terminate Regeneration Mode If the alarm cannot be reset, or if the alarm condition UPS Alarm and Status Messages UPS Alarm and Status Messages Page Ne t ItiTi n That