Summary of Contents for Emerson Liebert NXL 250 kVA
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AC Power For Business-Critical Continuity™ Liebert ® ™ Operation and Maintenance Manual–250-1100kVA, 60Hz, Three Phase Single-Module & Multi-Module...
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® Contacting Emerson Network Power for Support Contact Emerson Network Power Liebert Services for information or repair service in the United ® States at 1-800-LIEBERT (1-800-543-2378). For repair or maintenance service outside the 48 contiguous United States, contact Liebert Services, if available in your area.
Important Safety Instructions MPORTANT AFETY NSTRUCTIONS SAVE THESE INSTRUCTIONS This manual contains important instructions that should be followed during installation and maintenance of your Liebert NXL UPS and DC source. WARNING Risk of electric shock. Can cause equipment damage, injury or death. Exercise extreme care when handling UPS cabinets to avoid equipment damage or injury to personnel.
Introduction NTRODUCTION General Description The Liebert NXL UPS provides continuous, high-quality AC power to your business-critical equipment, such as telecommunications and data processing equipment. The Liebert NXL UPS supplies power that is free of the disturbances and variations in voltage and frequency common to utility power, which is subject to brownouts, blackouts, surges and sags.
Introduction Modes of Operation 1.2.1 Normal Mode Operating in normal mode, the Liebert NXL’s rectifier derives power from a utility AC source and supplies regulated DC power to the inverter, which regenerates precise AC power to supply the connected equipment. The rectifier also uses the utility source power to charge the DC sources. 1.2.2 Bypass Mode When the Liebert NXL is in bypass mode, the load is directly supported by utility power and is...
Introduction Options A number of options are available from Liebert for your UPS system. (Some options are not available for all ratings.) Described below are the most frequently provided options. Other options are available. Contact your Liebert sales representative for more information. •...
Operation PERATION The Liebert NXL UPS is equipped with a microprocessor-based display touchscreen designed for convenient and reliable operation. The display is driven by an easy-to- follow, menu-prompted software. Features The Liebert NXL interface display enables the operator to perform such tasks as: •...
Operation Figure 14 Monitor/mimic display example: load on bypass, UPS On Green – Normal Orange – Marginal Gray – Absent Black – Unknown Figure 15 Monitor/mimic display example: load on bypass, UPS module Off Green – Normal Orange – Marginal Gray –...
Operation Navigation Touchscreen 2.2.1 Main Display Screen Several menu items can be accessed from the main display screen (see Figure 10). These menu items are detailed in subsequent sections. 2.2.2 Configurations Menu Rating This menu item will display a popup showing the following parameters (see Figure 16). These parameters are entered during commissioning when the UPS is installed.
Operation User Settings System Settings These display settings can be changed from the touchscreen. Press the box to the left of each parameter to bring a popup window that will allow the parameter to be changed. • Backlight Brightness—High or Low (default: Low) •...
Operation Adjustable Setpoints These warning and alarm settings can be changed from the touchscreen. Press the box to the left of each parameter to bring a popup window that will allow the parameter to be changed. Max Load Alarm The module will activate a warning when the load is above any of these settings: •...
Operation Battery Management These DC source settings can be changed from the touchscreen. Press the box to the left of each parameter to bring a popup window that will allow the parameter to be changed. Battery Equalize When Battery Equalize is activated (Manual Battery Equalize button under Batt Mgt), the module will charge the batteries to the Equalize Voltage for the length of Equalized Time.
Operation Event Management This menu item permits changing how the Liebert NXL handles Alarms, Faults and Status information. Each event can be configured for the following: • Latch (yes/no)—Event stays active in the event window, even if the fault condition has been cleared, until user acknowledges it by pressing the “Reset”...
Operation Startup Menu This menu is used to start the UPS and individual devices. Manual—This will begin the UPS startup. See 2.15 - Manual Operations—All Systems for details. Devices • Close Trap—This will start the Input filter, if installed • Close MBD/BCB—If the MBD is motor-operated, the Close command will enable and energize the motor to close.
Operation Battery Management Menu This menu permits configuring DC source settings. Time Remaining Graph—Displays the time remaining graph in the multipurpose window; plot the DC source voltage against elapsed time during a Battery Discharge Cycle (see Figure 24). The bottom black line is voltage when the module has reach End of Discharge. This line is programmed during commissioning.
Operation Manual Battery Test—Start/Stop Manual Battery Equalize—Start/Stop; must be enabled by Emerson Network Power Liebert Services to be active Battery Cycle Monitor—Displays how many discharges have occurred for these time periods: 0-30sec, 31-90sec, 91-240sec, 4-15min, 15-30min, 30-60min, 60-240min, 4-8hr, 8hr and up. Each discharge record will include: (see Figure 25) •...
Operation Figure 26 Battery cycle monitor summary System View—1+N Systems Only System View will display the status of each of the system breakers (MOB’s, MIB, MBB). It will display the system output information including, voltage, current, kVA/kW, frequency and number of redundant modules in the system.
Operation This button will show the following status of each module in the system: • Comms • Normal—UPS intermodule communication is working properly • Failed—UPS intermodule communication is not working properly • Events • None—UPS has no active events • Alarms—UPS has an Alarm •...
Operation 2.13 Silence This button will silence the audible alarm. 2.14 Modes of Operation This section illustrates the flow of power through circuit breakers, switches and UPS components during various modes of operation. The same modes of operation apply to all configurations of the Liebert NXL.
Operation 2.14.2 OK to Transfer The OK to Transfer status message will be displayed when the bypass line and UPS output power are both available, their voltage, frequency and phase synchronization are matched within specifications, and the Static Switch Disconnects are closed (ON). An alarm message may be displayed to indicate Load On Bypass (Figure 30).
Operation 2.14.3 Input Power Failure—Load on DC Source If the utility AC power source fails or is outside the acceptable range, the DC source becomes the power source for the UPS module inverters. The UPS continues to supply power to the critical load and also to the UPS controls.
Operation 2.14.5 Emergency Module Off (Optional) The Emergency Module Off (EMO) mode will transfer the critical load to the bypass line and remove power from all UPS module components except the controls, bypass circuit breaker and the static switch. If installed, the Emergency Module Off control is a guarded pad next to the display touchscreen (Figures 2, 6 and 7).
Operation 2.14.7 ECO Mode When ECO Mode is active, the critical load is supported by the bypass source. The rectifier is On and providing power to the DC source for charging. The inverter is on standby, available to provide power to the critical load if a fault occurs on the bypass line.
Operation 2.15.1 Startup—Single Module System This section lists typical step-by-step instructions. The touchscreen will list all steps required for the process, based on the unit’s condition and other factors. WARNING Risk of electrical shock. Can cause equipment damage, personal injury and death. The following procedure provides power to the critical load distribution system.
Operation Press OK to continue. This will energize the load on the UPS internal bypass. The message “Close CB1” will appear. d. Close CB1 (see Figures 2, 6 and 7). The “Press OK to Issue Rectifier On Command” message will appear. e.
Operation 2.15.2 Startup—N+1 System The following instructions will start an individual UPS module. Repeat these steps for all the UPS units in the system that will be started. This section lists typical step-by-step instructions. The touchscreen will list all steps required for the process, based on the unit’s condition and other factors.
Operation 9. Close all Battery/DC breakers associated with this module. The UPS will stay in this mode until all breakers are closed. Skip this command if the DC sources are not ready to be started. The DC breakers can be closed later from the startup command (see 2.5 - Startup Menu).
Operation Startup—1+N System with External Maintenance Bypass 1. Before applying power to the UPS modules, determine the position of the following circuit breakers and switches: • Input Circuit Breaker (CB1)—Verify that this breaker on the front of the UPS cabinet is in the open position (see Figures 2 and 6 for the location).
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Operation 3. If the system has optional Bypass breakers (MBB/MIB), the message “Close MBB” will appear in the multipurpose window. a. Close the MBB breaker. The message “Press OK to begin startup of this module” will appear. b. Press “OK” to continue. This will begin the startup procedure for the UPS module. The message “Close BFB”...
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Operation Startup—1+N System Without External Maintenance Bypass 1. Before applying power to the UPS modules, determine the position of the following circuit breakers and switches: • Input Circuit Breaker (CB1)—Verify that this breaker on the front of the UPS cabinet is in the open position (see Figures 2 and 6 for the location).
Operation 16. Perform Steps 10 through 14 on the rest of the UPS units in the system ready to be placed on line. This message will appear: “This Module Startup is complete. Finish the All Module Startup in process or proceed to the Transfer menu to transfer.” 17.
Operation 2.15.5 Maintenance Bypass Load Transfers—Single Module System Follow these instructions to manually transfer the load between the Maintenance Bypass and the UPS bypass line. Do not transfer the load between the Maintenance Bypass and the UPS module (inverter) output. Use the Monitor/Mimic Display screen to verify that the UPS bypass line is available.
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Operation Maintenance Bypass Load Transfers—Single Module System: If Load is on UPS Bypass 1. Transfer the UPS system to bypass (see 2.15.4 - Load Transfer and Retransfer—Single Module System). The “OK to transfer” lamp on the key-release unit will light. NOTE If the maintenance bypass cabinet or switchboard has any other type of custom interlock, follow the specific instructions for that interlock system to remove the key.
Operation 2.15.6 Load Transfer—N+1 System: Remove UPS from N+1 System (Collective) 1. Press the “Transfer” menu button on the touchscreen. The Connect/Remove Inverter screen will appear in the multipurpose window (see Figure 40 - N+1 Transfer menu commands). 2. Press “Remove Inverter” button. This will open CB2. NOTE If disengaging this UPS from the system will cause the other UPS units in the system to overload, then the “Remove Inverter”...
Operation 2.15.8 Load Transfer—1+N System: Remove a UPS from System (Collective) 1. Under the “Transfer” menu button on the touchscreen, press the “This Module” button. The Transfer/Retransfer screen will appear in the multipurpose window (see Figure 41). 2. If the system has enough capacity to turn Off the unit, press the “Remove Inverter” button. This will open CB2.
Operation 2.15.9 Load Transfer—1+N System: Add a UPS to the System (Collective) This section lists typical step-by-step instructions. The touchscreen will list all steps required for the process, based on the unit’s condition and other factors. 1. Provide power to all the UPS controls to permit the display touchscreen and system logic to function properly.
Operation 2.15.10 Load Transfer—1+N System: Transfer System to Bypass 1. Under the “Transfer” menu button on the touchscreen, press the “All Modules” menu button. The Transfer/Retransfer screen will appear in the multipurpose window (see Figure 43). 2. If the UPS outputs are synchronized with their bypass, press the “1+N Bypass” button. This will turn On all available static switches and open CB2 in all the modules.
Operation 2.15.12 Load Transfer—1+N System: Transfer to Maintenance Bypass Follow these instructions to manually transfer the load between Maintenance Bypass and the System Static Bypass. Do not transfer the load between Maintenance Bypass and the System Inverter output. Use the Monitor/Mimic Display screen to determine whether the UPS bypass line is available. Load Transfer—1+N System: Transfer to Maintenance Bypass if Load is on System Static Bypass This section lists typical step-by-step instructions.
Operation 2.15.13 Shutdown—Single Module UPS System Perform a Module Shutdown to remove power from a UPS module. Read all warnings in 4.0 - Maintenance before performing any maintenance on your Liebert NXL UPS. These warnings and cautions must be observed during any work on the UPS. NOTE Service and maintenance work must be performed only by properly trained and qualified personnel and in accordance with applicable regulations as well as with manufacturers’...
Operation 2.15.14 Shutdown—N+1 UPS System Perform a Module Shutdown Procedure when you want to disconnect power from a UPS module. For System shutdown, see the SCC operation and maintenance manual, SL-25514, available at the Liebert Web site: www.liebert.com Read all warnings in 4.0 - Maintenance before performing any maintenance on a Liebert NXL UPS. These warnings and cautions must be observed during any work on the UPS.
Operation 2.15.15 Shutdown—1+N UPS: UPS Shutdown This section lists typical step-by-step instructions. The touchscreen will list all steps required for the process, based on the unit’s condition and other factors. Perform a Module Shutdown Procedure to remove power from a single UPS module in the system. Read all warnings in 4.0 - Maintenance before performing any maintenance on your Liebert NXL UPS.
Operation 2.15.17 1+N System Shutdown This section lists typical step-by-step instructions. The touchscreen will list all steps required for the process, based on the unit’s condition and other factors. Perform a System Shutdown Procedure when you want to remove power from the entire UPS system. Read all warnings in 4.0 - Maintenance before performing any maintenance on your Liebert NXL UPS.
Operation To isolate the system, open all MOB breakers and utility feeds to the bypass and rectifier inputs. Figure 46 1+N System Shutdown menu commands ® ™ Liebert...
Operation 2.16 Automatic Operations The Liebert NXL UPS system is designed to function while unattended by an operator. The system control logic monitors the performance of the UPS, the availability of power sources and the current required by the critical load. The system control logic: •...
Operation 2.16.2 Automatic Transfers to Bypass (Overload Condition) The UPS system will initiate an automatic load transfer to the bypass line if an overload condition exceeds the current-versus-time curve of overload capacity or if specified UPS system faults occur. Load On Bypass is illustrated in Figure 30. The Overload Transfer and Output Undervoltage alarm messages will initiate an automatic transfer to bypass and the Load On Bypass message will be displayed.
Operation 2.16.4 Automatic Retransfers to UPS In an automatic retransfer, the two circuit breakers (bypass and inverter output) are both closed simultaneously for a short period of time (overlap). The following critical bus conditions must be present to initiate an automatic retransfer of the critical load from the bypass source to the UPS inverter: 1.
Options PTIONS NOTE These items must be enabled by service before they become functional. If a feature is disabled, the feature will not be available and the menu item will not be displayed. Input Contact Isolator Board The Input Contact Isolator Board (ICI) provides a Liebert NXL module interface for up to eight external user alarm or message inputs to be routed through the NXL’s alarm network.
Options • Assignment—Custom, Pre-assigned (default: “Input Contact” XY) • Delay, sec—0 to 99.9 (default: 0) • Message—Custom: 0-19 characters 3. To assign labels for each channel: a. Press Pre-assigned for default labels on Channels 1-6 (See Table 1) b. For Custom labels 1.
Options Programmable Relay Board The Programmable Relay Board (PRB) provides a means to trigger an external device when an event occurs in the Liebert NXL. Each PRB has eight channels. Each channel has Form-C dry contacts rated at 1A @ 30VDC or 125VAC @ 0.45A. Any alarm/event can be programmed to any channel or channels.
Options 3.2.1 Configuring the Programmable Relay Board Settings 1. Press Internal Option Settings from the Config menu. 2. Press which Programmable Relay Board will be configured. The Programmable Relay Board dialog box is displayed. 3. Press the Relay channel 4. Press up to four (4) events. Selected events will show up under Relay 1 Assignment. NOTE To deselect an event, click on the event.
To test the LEDs, press the Lamp Test/Reset push button. This lights all of the LED indicators for visual inspection. If an LED indicator does not respond to the lamp test, contact your local Emerson Network Power representative for assistance.
Options 3.4.2 LBS Configurations • Load Bus Sync – Enable or Disabled (default: Disable) • LBS Master Select - Master or Slave (default: Slave) NOTE The LBS settings permit proper operation with only one UPS set as the Master unit. •...
Options 3.4.6 Slave System Any unit designated as the Slave upon power-up / reset will monitor and lock to the Master LBS Sync Pulse. When the Slave unit is on bypass, the Slave will generate the LBS Sync Pulse. • The Slave will slew to be locked to its own bypass source. The inverter in the LBS Slave system will follow the local bypass.
Options 3.5.2 Operation ECO Mode can be started either manually or automatically. Manually—If “Continuos Operation” is enabled under ECO Mode - Operations, pressing Start will activate ECO Mode. Automatically—If ECO Mode schedule has been programmed (see Figure 54), the system will start ECO Mode at the next scheduled start time.
Options 3.5.3 Bypass Qualification limits All of the following conditions must be true to qualify ECO Mode operations based on the bypass source: • Bypass voltage is within Manual Transfer Bypass Voltage High Limit setting and Manual Transfer Bypass Voltage Low Limit setting or Max Bypass range of ±10% •...
Options Intelligent Paralleling Intelligent Paralleling is intended to increase system efficiency and reduce operating hours on the modules. Intelligent Paralleling will put one or more paralleled modules into standby operation when the number of redundant modules is above the user specified threshold. 3.6.1 Intelligent Paralleling Setup Operation...
Options 3.6.2 Intelligent Paralleling Target Area The Intelligent Paralleling Target Area is the Number of Redundant Modules that fall between the Minimum System Redundancy setting and the internal Maximum System Redundancy (Minimum System Redundancy + 1.25). • The Maximum Number of Redundant modules is designed to provide hysteresis so that modules are not started and stopped when the load oscillates a few percentage points.
Options 3.6.6 Module Standby Rotation Module Standby Rotation will limit the time a module is in standby operation when the Number of Redundant Modules doesn't change for a long period. • The module selected as the next to terminate Intelligent Paralleling per Module Selection - Termination, (see Intelligent Paralleling Module Termination on page 65), will not be in standby operation for longer than Maximum Time Module In Standby (see 3.6.1 - Intelligent Paralleling Setup).
Options Figure 56 Module standby rotation Load UPS1 UPS2 UPS3 UPS4 UPS5 After Maximum Time Module in Standby setting time Load UPS1 UPS2 UPS3 UPS4 UPS5 After Maximum Time Module in Standby setting time Load UPS1 UPS2 UPS3 UPS4 UPS5 After Maximum Time Module in Standby setting time...
Risk of electrical shock and high short circuit current. Can cause equipment damage, personal injury and death. Always identify connecting wiring prior to disconnecting any wiring. Do not substitute parts except as authorized by Emerson ® Maintain the UPS cabinets free of foreign materials such as solder, wire cuttings, etc.
Mission-critical sites can have the standard parts-and-labor, around-the-clock coverage for their UPS, with or without scheduled preventive maintenance visits. Other sites can benefit from a variety of money-saving options. Emerson recommends two preventive maintenance visits per year for the UPS. The first can be ®...
Maintenance Routine Maintenance You should become thoroughly familiar with the equipment, but at no time should you go beyond the specific procedures in this manual while performing maintenance or correcting a malfunction. If you have any doubt as to what must be done, call Liebert Services at 1-800-LIEBERT for further instructions.
Maintenance 4.3.3 Limited Life Components The Liebert NXL UPS has a design life well in excess of 10 years. Well-maintained units can continue to provide economic benefits for 20 years or more. Long-life components are used in the UPS wherever practical and cost-effective.
Maintenance 4.4.1 Battery Safety Precautions Servicing of batteries should be performed or supervised by personnel knowledgeable of batteries and the required precautions. Keep unauthorized personnel away from batteries. When replacing batteries, use the same number and type of batteries. WARNING Risk of electric shock, explosive reaction, hazardous chemicals and fire.
Maintenance WARNING Risk of electric shock, explosive reaction, hazardous chemicals and fire. Can cause equipment damage, personal injury and death. Do not use equalize charging with valve-regulated, lead-acid batteries. Refer to the battery manufacturer’s manual, available on the manufacturer’s Web site, for specific information about equalize charging.
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 Emerson can provide typical guidelines, the responsibility for the proper breaker trip ®...
Specifications PECIFICATIONS DC Sources 5.1.1 Battery Operation The separate battery manufacturer’s manual, available on the manufacturer’s Web site, provides the necessary information for the installation, operation and maintenance of the battery. Use the battery manual in conjunction with this manual. The float charge voltage for a battery is equal to the number of cells in series making up the battery multiplied by the charge voltage for each cell.
Specifications Table 9 Electrical specifications Input Parameters Input Voltage to Rectifier, VAC, 480V/575V/600V 3-phase, 3-wire Input Voltage to Bypass, VAC, 3-phase, 480V/575V/600V 3- or 4-wire Input Voltage Range, VAC +10% to -30% Input Frequency, Hz Permissible Input Frequency Range, 55 to 65 Reflected Input THDi at nominal 250-400kVA: <10% voltage at full load, %...
UPS Alarm and Status Messages A - UPS A PPENDIX LARM AND TATUS ESSAGES Table 10 shows alarm and status messages as they appear in the Liebert NXL’s touchscreen and in the history log, along with a description and recommended actions, if any. If the recommended action fails to correct the condition, contact your factory-authorized service pro- vider.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Observe the One-Line Display. If the input line is orange, black, or gray, the battery discharging condition is normal.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Observe the One-Line Display. To identify which battery cabinet is reporting the temperature condition, press the “Battery Box”...
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. To attempt to identify which sensor is reporting an inconsistent temperature or an overheating battery, observe the temperature reading inside the Battery Box on the One-Line Display.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action When starting the module BPSS's in a 1+N system without a MBB, there are not enough module BPSS's ready with their MOB closed to Press “SILENCE”...
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. The critical load is greater than 110% while the Observe the calculated load percentage on C UPS is on bypass.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Press “RESET” to clear the fault. The negative DC Bus has a ground fault. Perform a visual inspection of the batteries.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Resolve the issue that precipitated the EMO. An Emergency Module Off (EMO) command has For safety, the UPS latches an EPO event.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action The UPS has tried to reconnect the inverter to the critical bus too many times. For a single module system, the load will be on the bypass static switch.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Check the Inlet Air Temperature on the One-Line Display and verify the reading is accurate, i.e. is The air flowing into the UPS is too warm.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action An active Input Current Limit alarm means the detected input current (RMS) exceeds the limit Press “SILENCE” to silence the audible alarm. setpoint (default is 125%).
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action An overload condition is active on B phase. Press “SILENCE” to silence the audible alarm. B phase load condition exceeds 105%. Check the Module Output Meter and note the B A countdown timer is displayed on the One-Line phase load percentage.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action This UPS system has been enabled as the functional Master Load Bus Synchronization (LBS) system. The functional Master is sending the LBS sync Under normal circumstances, none.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action One or more battery circuit breakers are open. This alarm applies if the system includes more than one battery circuit breaker, and at least one Press “SILENCE”...
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Therefore, it will be necessary to utilize inverter automatically maintenance bypass by closing the optional external Maintenance Bypass Breaker (MBB). Emerson recommends that the user or operator speak with an authorized service associate from Emerson before attempting this operation. Maintenance...
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action The condition clears from the Active Event Window when manual transfers are enabled. A possible reason for this condition is an unstable generator.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action The user adjustable maximum load alarm threshold was exceeded. This is a “notification only” type alarm, meaning the UPS takes no Press “SILENCE”...
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action The condition clears from the Active Event Window when manual transfers are enabled. Possible reasons for this condition are: 1. With the collective on UPS inverters and Module Output Breaker (MOB) open (if installed) active or 2.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action The difference between the inlet air temperature Press “SILENCE” to silence the audible alarm. and the outlet air temperature is too great. Check the Inlet Air Temperature on the One-Line This alarm means excessive heat is being Display and verify the reading is accurate, i.e.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Observe the One-Line Display and the Active Event Window for current UPS condition - On Battery? Observe the color of the Bypass Line on the One- Line Display.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Regeneration Mode is a service mode that is normally controlled by the service technician. Regeneration Mode Status or Alarm messages Under normal circumstances, none.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action Press “SILENCE” to silence the audible alarm. Use the System View on the touchscreen to see The control has detected a communication what modules are not communicating.
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UPS Alarm and Status Messages Table 10 Liebert NXL alarm and status messages (continued) Event Message Event Definition Recommended Action System Output The system output breaker indicates that it is in Breaker (UOB) the open position. Open System One or more modules in a multi-module system Overload is reporting an overload on at least one phase.
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UPS Alarm and Status Messages NOTES ® ™ Liebert...
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