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Electrical Connections
2.1.5Safety Ground
The safety ground busbar is located below the Maintenance Bypass circuit breaker as shown in Figure 4. The safety ground cable must be connected to the ground busbar and bonded to each cabi- net in the system.
All cabinets and cable conduit should be grounded in accordance with local regulations.
! WARNING
Failure to follow proper grounding procedures can result in electric shock hazard to personnel or the risk of fire, should a ground fault occur.
NOTE
Proper grounding significantly reduces electromagnetic interference problems in systems.
NOTE
The ground busbar is easily accessible when the lower protective cover plate is removed.
2.1.6Protective Devices
For safety, it is necessary to install circuit breakers in the input AC supply and external battery bat- tery cabinets, external to the UPS system. Given that every installation has its own characteristics, this section provides guidelines for qualified installation engineers with knowledge of operating prac- tices, regulatory standards and the equipment to be installed.
UPS Rectifier and Bypass Input Supply
•Protection from excessive overcurrents and short circuits in power supply input
External overcurrent protection for the AC output circuit is to be provided. See 5.4 - UPS Elec- trical Characteristics and Table 9 for overload capacity.
When an external battery supply not made by Liebert is used, the customer must provide overcur- rent protection for the battery circuit.
•Dual Input
When wiring the UPS with dual inputs, the Rectifier input and the Bypass input must be pro- tected separately. Size the breakers according to the input currents shown in Table 8. In dual input configuration, the neutral wire of each source should be connected together to guarantee dual source has the same voltage potential to earth.
Liebert NX UPS
Page
Table of Contents
UPS Specifications
Options
Operator Control and Display Panel
Pop-Up Windows
Operating Instructions
Appendix a UPS Status Messages
Specifications and Technical Data
Tables
Page
Important Safety Instructions
Battery Cabinet Precautions
Glossary of Symbols
External Inspections
Installation
Internal Inspections
Preliminary Checks
UPS Location
Considerations in Moving the Liebert NX
Battery Location
Mechanical Considerations
Special Considerations for Parallel Systems
Clearances
Floor Installation
Cable Entry
System Composition
Cabinet arrangement-Liebert NX units and battery cabinets
UPS
Power Cabling
Cable Rating
Lug Size and Torque Requirements
Cabling Guidelines
UPS Input Configuration
Input and output busbars
Cable Connections
Safety Ground
Protective Devices
UPS Rectifier and Bypass Input Supply
Output System Connections-Ensure Correct Phase Rotation
Cabling Procedure
Common Input Connections
Dual Input Connections
Frequency Converter Mode
Monitor Board Features
Control Cables
Dry Contacts
Maintenance bypass cabinet interface
Maintenance Bypass Cabinet Interface
Input Dry Contacts
Input dry contacts at
BCB control interface
BCB Control Interface
Main input fault relay center
Inverter mode relay center
Output Dry Contacts
Output dry contact relays
EPO Input-Optional
EPO input contact relays
Indicates Pin
Introduction
Safety
Battery Cabinets
External Battery Cabinet Installation
Connecting the Batteries
Installation Considerations
Insulated Post Tray Handle For Cabling
Connecting the Battery Cabinet to the UPS
Non-Standard Batteries
BCB Shunt Trip
Alber Monitoring System-Optional
This power must be UPS protected
Load Bus Synchronization
LBS Cable and Settings
Performance Requirements
LBS Cable
Configuring Parallel System Operation
Features of Parallel System
General
Installing Parallel System
Operating Principles Redundancy Paralleling
Operation Modes Summary
Power Cables
Cabinet Installation
Conditions for Parallel System
Preliminary Checks
Interconnecting
Auxiliary Dry Contact Cables
Cables
Q1Ext Q2Ext
QByp
To Load
Normally Closed EPO
Normally Open EPO
Environmental characteristics
UPS Mechanical Characteristics
UPS mechanical characteristics
Conformity and Standards
UPS terminal
UPS Electrical Characteristics
Liebert approved replacement batteries
Rectifier input power
Rated Power kVA 100 120
Battery Manufacturer Models Supplied
DC Intermediate Circuit
Inverter Output
Bypass Input
Left Side
GND
Left Side View Front View
Max. Door Swing
U3819205
Batt
Ext
530628 Pg , Rev
External Battery Cabinet
Battery Breaker
Auxiliary Contacts
Top
Top Front Right Side
System
Front Rear
Rear
FRONTOutput
Run From Conductors
Ph A, B, C UPS Inputs
Ph A, B, C System Input
Ph A, B, C UPS Outputs
AC Output
Utility UPS #1-UPS #4 Module AC Ph A, B, C UPS Inputs
Ph A, B, C System Outputs
Ground UPS
U3819301
Isometric View
General Description
Single module block diagram dual input configuration
Battery Mode
Normal Mode
Bypass Mode
Bypass Supplies
Parallel Redundancy Mode System Expansion
Maintenance Mode
Display Panel Layout
Operator Control Panel
Detailed view of control panel
Mimic indicators Control buttons Navigation keys
Mimic display status indicators
Mimic Display Indicators
Control buttons
Control Buttons
LCD Overview
Audible Buzzer
UPS System Information
Navigation Keys
Icons for navigation keys
Description of items in UPS system window
LCD Menus and Data Items
Menu Type Item Type Explanation
Descriptions of UPS menus and data window items
Mains
Input
Start/stop Battery
Language Selection
Tests
Set date and time
Current Date and Time
Current status and history log records
UPS Status Messages
Default Screen
Types of LCD Screens
Opening Display
Screen Saver Window
UPS Help Screen
Pop-Up Windows
UPS operating modes
Liebert NX Operating Modes
Circuit breakers
Circuit Breakers
Startup Procedure
Indicator State
UPS Startup
Switch from Bypass Mode to Normal Mode
Switch from Normal Mode to Bypass Mode
Maintenance Bypass Procedure and Powering Down the UPS
Emergency Shutdown With EPO
Auto Restart
Multi-Module System Procedures
Battery Protection
Battery Undervoltage Pre-Warning
Battery End-of-Discharge EOD Protection
Tie breaker
LED Function Status
Inserting One Module into a Multi-Module System
Commissioning a Parallel System
Shutdown Procedure-Complete UPS and Load Shutdown
Parallel System Start Up
Communication and Other User Terminals
Power Output
Analog Input Interface
Liebert IntelliSlot Communication
Liebert NX communication options
See 10.1.5 Configuring
Comments
Baud Rates
Configuring Baud Rates
Liebert IntelliSlot Web card display
Relay card jumper configuration
Relay Card pin configuration
Relay Card
Pin Function Operation
MultiPort 4 Card
Assignment
Pin Description
Remote Alarm Monitor
LBS Mode-Load Bus Synchronization
Replacing Dust Filters
Battery torque rating
Torque specifications
Lug Size and Torque Requirements
Cable Lengths Floor to Connection Point Inside UPS
Parallel system current table
Distance to connection points on the Liebert NX UPS
External cabinet dimensions, including side panels
Cable size and tightening torques
Lead/Lag ratings
250 10 N*m
Estimated battery run time, minutes
Battery Run Times
Services at 800-543-2378 for assistance
UPS status messages
Event Message Description / Suggested Action if any
Bypass voltage is beyond the normal range
High ambient air temperature
Bypass voltage exceeds the limit
Software according to the customer’s agreement
Alarm if applicable
Error can also leads to the alarm
Inverter STS Fail
Condition is removed
EPO
Emergency Power Off
UPS status messages
UPS Status Messages
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