Vertiv Liebert APM2 User manual

Liebert® APM2
User Manual
30 to 120 kVA Modular UPS

Proprietary and Confidential ©2023 Vertiv Group Corp.
Technical Support Site
If you encounter any installation or operational issues with your product, check the pertinent section of this
manual to see if the issue can be resolved by following outlined procedures.
Visit https://www.vertiv.com/en-us/support/ for additional assistance.
The information contained in this document is subject to change without notice
and may not be suitable for all applications. While every precaution has been
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assumes no responsibility and disclaims all liability for damages result from use
of this information or for any errors or omissions.
Refer to local regulations and building codes relating to the application,
installation, and operation of this product. The consulting engineer, installer,
and/or end user is responsible for compliance with all applicable laws and
regulations relation to the application, installation, and operation of this product.
The products covered by this instruction manual are manufactured and/or sold
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

TABLE OF CONTENTS
1 Important Safety Instructions 1
1.1 Product Safety 1
1.2 Disclaimer 1
1.3 Safety Precautions 2
2 Overview 5
2.1 Features 5
2.2 Design Concept 5
2.2.1 System design 5
2.2.2 Bypass 9
2.2.3 System control principle 9
2.2.4 UPS power supply switch configuration 10
2.2.5 Battery circuit breaker (BCB) 13
2.3 Parallel System 14
2.3.1 Parallel system features 14
2.3.2 Parallel system requirements 14
2.4 Operation Modes 14
2.5 Battery Management System (BMS) 19
3 Mechanical Installation 21
3.1 Precautions 21
3.2 Transportation 21
3.3 Tools 22
3.4 Unpacking 23
3.5 Pre-installation Inspection 26
3.6 Environmental Requirement 26
3.6.1 UPS location selection 26
3.6.2 Battery location selection 26
3.6.3 Storage 27
3.7 Mechanical Requirement 27
3.7.1 Composition 27
3.7.2 Moving the cabinet 27
3.7.3 Clearance 28
3.7.4 Cable access mode 28
3.8 Installation Drawings 29
4 Electrical Installation 33
4.1 Wiring of Power Cable 33
4.1.1 System configuration 33
4.1.2 Maximum steady state AC and DC currents 33
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

4.1.3 Recommended CSA of UPS cable 34
4.1.4 Selection of UPS I/O switch 34
4.1.5 Distance between the UPS connection point and floor 34
4.1.6 General information 35
4.1.7 Power cable connecting terminal 35
4.1.8 Protective ground 35
4.1.9 External protective devices 35
4.1.10 Power cable connection steps 37
4.2 Wiring of Signal Cable 41
4.2.1 Overview 41
4.2.2 Dry contact port X6 J3 42
4.2.3 Dry contact port X6 J22 44
4.2.4 Output dry contact X7 J1 (option) 45
4.2.5 Output dry contact X7 J2 (option) 46
4.2.6 Output dry contact X7 J3 (option) 47
4.2.7 REPO port 47
4.2.8 Host communication port 48
4.2.9 Parallel and LBS communication ports 49
4.2.10 Vertiv™ Liebert® IntelliSlot™ port 49
4.2.11 BMS module port 50
4.2.12 Signal cable connection steps 51
4.3 Built-in Lead-acid Battery Module Installation 51
5 Operator Control and Display Panel 53
5.1 Introduction 53
5.2 Navigating through the Vertiv™ Liebert® APM2 Touchscreen 54
5.2.1 Access level login 54
5.2.2 Vertiv™ Liebert® APM2 touchscreen control panel components 55
5.2.3 Menu 56
5.3 Operation 61
5.3.1 Login to the Vertiv™ Liebert® APM2 touchscreen control panel 61
5.3.2 Customizing the display 62
5.3.3 Operator controls 68
5.4 Viewing UPS Status 75
5.4.1 Viewing UPS data with the status gauge 75
5.4.2 Viewing UPS data with the status panel 79
5.4.3 Logs alarms and events 84
5.5 Viewing UPS Component Status 86
5.6 Status Bar Component 89
5.6.1 Status bar messages 89
5.7 Alarm List 93
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

6 Single UPS Operation 101
6.1 Introduction 101
6.1.1 Precautions 101
6.1.2 Power switch 101
6.2 UPS Startup Procedures 102
6.2.1 Startup procedures in normal mode 102
6.2.2 Startup procedures in ECO mode 110
6.2.3 Startup procedures in battery mode (battery cold start) 111
6.3 Procedures for Transfer Between Operation Modes 112
6.3.1 Transfer from normal mode to battery mode 112
6.3.2 Transfer from normal mode to bypass mode 112
6.3.3 Transfer from Bypass Mode to Normal Mode 113
6.3.4 Transfer from normal mode to maintenance mode 114
6.3.5 Transfer from maintenance mode to normal mode 115
6.4 Battery Test Procedures 115
6.5 UPS Shutdown Procedures 117
6.5.1 Procedures to completely power down the UPS 117
6.5.2 Procedures for completely powering down UPS while maintaining power to load 118
6.6 EPO Procedures 118
6.7 UPS Reset Procedures after EPO 118
6.8 Automatic Restart 118
6.9 Selecting Language 119
6.10 Changing Current Date and Time 120
6.11 Control Password 121
7 Battery 123
7.1 Battery Types 123
7.1.1 Charging/discharging management 123
7.1.2 Advanced function 124
7.1.3 Battery temperature compensation 125
7.2 Battery Protection 125
7.3 Battery Balanced Voltage 126
7.4 Operation of Charger 126
7.5 Battery Cold Start 127
7.6 Safety 127
7.6.1 Hazardous battery voltage present behind covers 127
7.7 UPS Battery 130
7.8 Precautions for Installation Design 130
7.9 Battery Installation Environment and Number of Batteries 130
7.9.1 Installation environment 130
7.9.2 Fresh air volume (EN50272-2001) 130
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

7.9.3 Number of batteries 131
7.10 Battery Protection 132
7.11 Battery Installation and Connection 132
7.12 Design of Battery Room 133
7.13 Common Battery String 133
7.14 External BCB Cabinet (Optional 1) 134
7.15 BCB Box (Optional 2) 136
7.16 Battery Ground Fault Detector (Optional) 139
7.17 BCB Reference Current and Connection 140
7.18 Battery Maintenance 142
7.19 Disposal of Used Battery 142
8 Parallel System and LBS System 143
8.1 General 143
8.2 System Installation Procedures 143
8.2.1 Preliminary checks 143
8.2.2 Cabinet installation 143
8.2.3 External protective device 145
8.2.4 Power cable 145
8.2.5 Parallel cable 145
8.2.6 Remote emergency power OFF (EPO) 145
8.3 Operation Procedures for Parallel System 146
8.3.1 Startup procedures in normal mode 146
8.3.2 Maintenance bypass procedures 147
8.3.3 Procedures for isolating one UPS module from parallel system 148
8.3.4 Procedures for inserting one isolated UPS module in parallel system 148
8.3.5 Procedures for completely powering down UPS 149
8.4 LBS System 149
8.4.1 Cabinet installation 149
8.4.2 External protective device 151
8.4.3 Power cable 151
8.4.4 LBS cable 152
9 Vertiv™ Liebert® APM2 Option Configurations 155
9.1 Options List 155
9.2 Options Introduction 155
9.2.1 Battery temperature sensor kit 155
9.2.2 Battery ground fault kit 156
9.2.3 Seismic Anchor Kit 156
9.2.4 IS-UNITY-DP card 158
9.2.5 IS-UNITY-LIFE card 159
9.2.6 SIC card 159
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

9.2.7 IS-Relay card 160
9.2.8 UF-RS-485 card 162
9.2.9 BCB cabinet 163
9.2.10 Parallel cable 163
9.2.11 LBS cable 163
9.2.12 Shorting copper bar kit 163
9.2.13 LBS adapter 163
10 Communication 165
10.1 SNMP Protocol Communication 165
10.2 Modbus Protocol Communication 165
10.3 Dry Contact Communication 165
10.3.1 Communication through IS-Relay card 166
10.3.2 Communication through dry contact port of central control module 166
11 Service and Maintenance 167
11.1 Safety for Service and Maintenance 167
11.2 Service Procedures of Power Module and Bypass Power Module 167
11.2.1 Service procedures of power module 168
11.2.2 Replacement procedures of bypass power module 168
11.3 Key Components and Service Life of UPS 169
11.3.1 Life parameters and the proposed replacement time of key components 169
11.3.2 Replacement of air filter 169
11.4 Maintenance of UPS and Options 170
12 Specifications 171
12.1 Conformance and Standards 171
12.2 Environmental Characteristics 171
12.3 Frame 1 Mechanical Characteristics 172
12.4 Electrical Characteristics (Input Rectifier) 172
12.5 Electrical Characteristics (Battery Bus) 173
12.6 Electrical Characteristics (Inverter Output) 173
12.7 Electrical Characteristics (Bypass Input) 174
12.8 Efficiency and Loss 174
Appendices 176
Appendix A: Technical Support and Contacts 176
Appendix B: Glossary 177
Appendix C: Hazardous Substances and Content 178
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

1 Important Safety Instructions
This manual contains information about the installation and operation of the Vertiv™ Liebert® APM2 30 to 120 kVA UPS single
module and parallel system.
A Vertiv authorized engineer must install and commission the UPS. Failure to do so can cause product malfunction or
personal safety risk.
Read the UPS manual and safety precaution carefully, failure to do so can cause product malfunction or personal safety risk.
NOTE: The Liebert® APM2 30 to 120 kVA UPS is not manufactured to support the life support equipment.
WARNING! Never dispose of the internal or external battery of the UPS in a fire, as it may explode and
personnel safety is at risk.
1.1 Product Safety
1. If this product is stored or remain de-energized for a long period, it must be placed in a dry and clean
environment within specified temperature range.
2. The environmental requirements must be fulfilled while operating the UPS. See Environmental Requirement on
page26.
3. The UPS is designed for application in the following conditions:
•Where the temperature and relative humidity are not in specified range given in the Specifications on
page171.
•Is not subjected to vibrations or shocks.
•Where conductive dusts, corrosive gases, salts, or flammable gases are not present.
•Away from heat sources or strong electromagnetic interferences.
WARNING! The UPS with standard configuration is a product for commercial and industrial application in the
atmospheric environment (with dust, corrosion, electromagnetic interference). Installation restrictions or
additional measures may be needed to prevent disturbances.
1.2 Disclaimer
Vertiv disclaims all responsibility and/or liability for any defects or malfunction caused by the following actions:
•Any use or operation outside of the product Specifications on page171, including application ranges or operating
environments.
•Any unauthorized product operations, modifications or improper installation.
•Any forceful measures used when operating the product.
•Any other product related actions not in compliance with the instructions in this document.
If you need product assistance or have additional product questions, contact your Vertiv Technical Support representative.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

1.3 Safety Precautions
Always observe the following safety symbols.
WARNING! Used to alert the user to the risk of death or severe injury should the unit be used improperly.
NOTE: Used to alert the user to the risk of injury or equipment damage should the unit be used improperly.
IMPORTANT! Used to advise the user to carefully read and observe this unit though it may not cause damage.
Conformity and standards
This device complies with CE 2014/35/EU (Low Voltage Safety), 2014/30/EU (EMC) and 2011/65/EU (Rohs), as well as the
following UPS product standards:
•IEC62040-1 General safety requirements for UPS.
•IEC62040-2-EMC
•IEC62040-3 Performance requirements and test methods.
•IEC62040-4 Uninterruptible power supply systems (UPS). Part 4: Environmental factors. Requirements and
reports.
For details, refer to Specifications on page171.
Continued compliance requires installation in accordance with these instructions and the use of manufacturer approved
accessories only.
WARNING! High earth leakage current. Earth connection is essential before connecting input power
(including power supply and battery).
•This equipment is installed with an EMC filter.
•Earth leakage current is less than 3000 mA.
•Transient and steady state earth leakage currents, which may occur when the equipment is started, should be
considered in the selection of instantaneous RCCBs or RCD devices.
•RCCB which is sensitive to unidirectional DC pulse (class A) and insensitive to transient state current pulse must
be selected.
•The earth leakage currents of the load will be carried by the RCCBs or RCDs.
•The equipment must be earthed in accordance with the local electrical code of practice.
WARNING! Risk of voltage backfeed. Isolate the UPS, check for hazardous voltage between all terminals
including the protective earth before working on this circuit.
The UPS is fitted with a dry contact closure signal for use with an external automatic disconnect device (supplied by others)
to protect against backfeeding voltage into the incoming terminal through the rectifier or bypass static switch circuit. Place
the warning labels at all external at all external incoming primary supply disconnect device to warn service personnel that the
circuit is connected to a UPS.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

WARNING! The upstream distribution protection equipment of the UPS must be selected in accordance with
the local electrical regulations.
WARNING! All maintenance and servicing procedures involving internal access requires the use of a tool and
should be carried out only by trained personnel. There are no user serviceable parts behind the covers that
need a tool or wrench for removal.
WARNING! Battery voltage exceeds 400 VDC (For service personnel).
WARNING! Battery maintenance and servicing procedures require the use of a tool or key and must only be
performed by trained personnel. Pay attention when working with the batteries attached to this UPS, the
voltage at the battery terminal exceeds 400 VDC and can cause death.
Battery manufacturers provide details on precautions to be taken while operating when operating or in the vicinity of a large
battery. These precautions should be followed implicitly. Pay attention to the local environmental conditions and the provision
of protective clothing, first aid and fire fighting facilities.
WARNING! The APM2 UPS and battery circuit breaker box/battery cabinet have high voltage inside. The risk
of exposing to high voltage is reduced because the high voltage components can only be accessed when the
front door is opened.
There is no risk when operating this equipment according to the general instructions and the steps
recommended in this manual.
WARNING! This AMP2 UPS system receives power from more than one source. All AC source and the DC
source must be disconnected before servicing.
This UPS has several circuits that are energized with high AC as well as DC voltages. Check for voltage with
both AC and DC voltmeters before working within the UPS.
WARNING! When internal fuse of the UPS is damaged, it must be replaced with fuse of the same electric
parameters by qualified personnel.
IMPORTANT! The communication board is sensitive to electrostatic discharge, implement ESD prevention measures
when managing any communication board.
WARNING! Select an appropriate MCCB to protect against short circuit and overload for the battery. It is
recommended to use the Vertiv BCB box to provide a better solution.
WARNING! The power cables must be routed in the metal cable trough in order to avoid cable damage and
reduce the electromagnetic radiation.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

NOTE: The UPS meets the standard requirement of short time withstand current (Icw) of 10 kA. The specified
upstream fuses are required to obtain the conditional short circuit current rating, Icc at 65 kA symmetrical rms. It is
recommended to select the fuses in compliance with voltage of 690 V, current of 1500 A and breaking of 200 kA. The
specified upstream breakers should comply with an IEC 60269 series standard.
Product Model
120 kVA APM 0120kMK16FY02S00
Table 1.1 UPS Models
There are 3 types of cabinets for 120 kVA products.
1. UPS without switch.
2. UPS with maintenance switch Q3 cabinet.
3. UPS with input switch Q1, bypass switch Q2, maintenance switch Q3, output switch Q5 cabinet.
Hereinafter referred to as no switch, single switch, and four switches.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

2 Overview
This chapter describes the features, design concept, parallel system, operation mode, battery management and battery
protection of the Vertiv™ Liebert® APM2 30 to 120 kVA UPS. According to the model type, there are models with built-in
battery modules and models without built-in battery modules. According to the battery type, there are models with built-in
lithium battery modules and models with built-in lead-acid modules.
2.1 Features
The UPS is connected between a critical load, such as a computer, and mains power to provide high quality power for the
loads.
The UPS has the following advantages:
•Improves the input power quality.
•The UPS protects its output against the input power change through the intelligent controller.
•Protect the equipment in the scenario of mains direct power source failure.
•If the input power fails, the UPS will work in battery mode, and the power supply to the loads will not be
interrupted.
2.2 Design Concept
2.2.1 System design
This section describes the working principle of the UPS single module. The UPS adopts AC-DC-AC converter (as shown in
Figure 2.1 on the next page, Figure 2.2 on page7, and Figure 2.3 on page8). The first stage is conversion (AC/DC) adopts
three-phase high frequency rectifier to convert the three-phase input voltage into stable DC bus voltage.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

Figure 2.1 Block Diagram for Working Principle of UPS Single Module of Without Switch
Item Description Item Description
1 Input 7 Inverter
2 Output 8 Automatic inverter switch
3 Bypass input 9 UPS output
4 Static switch 10 Battery
5 Mains input 11 Battery charger/discharger
6 Rectifier
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

Figure 2.2 Block Diagram for Working Principle of UPS Single Module of with Single Switch
Item Description Item Description
1 Input 8 Rectifier
2 Output 9 Inverter
3 Bypass input 10 Automatic inverter switch
4 Maintenance bypass switch 11 UPS output
5 Static switch 12 Battery
6 Maintenance bypass 13 Battery charger/discharger
7 Mains input
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

Figure 2.3 Block Diagram for Working Principle of UPS Single Module of with Four Switches
Item Description Item Description
1 Input 9 Rectifier input switch
2 Output 10 Rectifier
3 Bypass input 11 Inverter
4 Maintenance bypass switch 12 Automatic inverter switch
5 Maintenance bypass 13 Output switch
6 Bypass input switch 14 UPS output
7 Static switch 15 Battery
8 Mains input 16 Battery charger/discharger
The UPS has its own battery charger and adopts advanced temperature compensation technology to effectively improve the
battery service life. The inverter adopts 3 level T-type IGBT topology and uses advanced SVPWM control technology to
derive the stable AC voltage from the DC bus voltage.
When the mains is normal, the rectifier and inverter work together to supply the power to the load and charge the battery.
When the mains is abnormal, the rectifier stops working, and the battery supplies power to the loads through the inverter. If
the battery voltage falls to end of discharge (EOD) voltage and the mains still has not been recovered, the UPS will shutdown
(if the system uses split bypass configuration and the bypass is normal, the system will transfer to bypass). The battery EOD
voltage is preset. When the mains is abnormal, the battery maintains the UPS operation till the battery voltage is reduced to
EOD voltage and the UPS shuts down, this time is called backup time. The length of backup time depends on the battery
capacity and the loads.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

2.2.2 Bypass
Through the intelligent control of the Static Switch module as shown in (Figure 2.1 on page6, Figure 2.2 on page7, and Figure
2.3 on the previous page). containing the controllable electronic switch, the loads can be supplied by the inverter or the
bypass. In normal situation, the loads are supplied by the inverter, in which case the automatic inverter switch at inverter side
is closed. In the case of overload (the overload delay time expires) or inverter failure, the automatic inverter switch is opened,
and the Static Switch module with UPS logic control will automatically transfer the loads to the bypass.
In normal operating state, to get the uninterrupted transfer between inverter and bypass, the inverter output must be
synchronized with the bypass.
Therefore, when the bypass frequency is within the synchronization range, the inverter control circuit will synchronize the
inverter output frequency with the bypass frequency and phase.
The UPS has a manual maintenance bypass switch (model without switch excluded) for shutdown of the UPS at the time of
maintenance. For maintenance, the bypass will directly supply power to the critical loads through the maintenance bypass.
NOTE: When the bypass maintenance mode supplies power to the load, the quality of the power supply may get
affected.
2.2.3 System control principle
Normal operation
Normal mode
The UPS has normal input mains, the rectifier and inverter operate normally. The inverter supplied power to the load, the
battery circuit breaker is closed, and the battery is in stable floating charge state.
For parallel system, as the UPS single module outputs are connected in parallel, the system checks that the inverter control
circuits are perfectly synchronized with one another and with the bypass in terms of both frequency and phase, and that they
have the same output voltages. Current supplied to the load is automatically divided among UPSs. A warning message
appears while synchronization is in progress.
Mains abnormal
When the mains fail or is abnormal, the rectifier will stop working automatically, and the system will transfer to battery output
(through inverter). The length of the operation time in battery mode depends on the load and the battery capacity. In the case
of Mains abnormal, if the battery voltage falls to the EOD voltage and the mains still has not been recovered, the inverter will
stop automatically, and the UPS touch screen will display alarm messages. If the system uses split bypass configuration and
the bypass is normal, the system will transfer to bypass.
Mains recovery
When the main power supply resumes normal within allowable time, the rectifier will start automatically and supply the load
and charge the battery again. Therefore, the power supply to the load will not be interrupted.
Disconnect battery
To disconnect the external battery from the UPS system for maintenance, use the external isolating switch. At this time,
except for the battery backup function upon mains power supply failure, other functions and all the steady state performance
of the UPS will not be affected.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

UPS module failure
For single module system, In case of inverter failure and output fuse blowout, the load will automatically transfer to the bypass,
and the output power supply will not be interrupted. In this situation, contact the local Vertiv technical support.
For parallel system, In the event of a fault in a UPS module, it will automatically exit from the parallel system. If the system is
still capable of providing the required load, the remaining modules will continue to supply the load with no interruption. If the
remaining modules are no longer capable of fulfilling the power requirements, the load will automatically transfer to the
bypass.
Overload
If the inverter is overloaded or the inverter current remains outside the Specifications on page171 (see Table 12.6 on
page173) longer than the specified time, the load will automatically transfer to the bypass without power interruption. If both
the overload and the current are reduced to a level within the specified range, then the load will be transferred back to the
inverter. In case of output short circuit, the load will be transferred to the bypass, and the inverter will shutdown. Five minutes
later, the inverter will start up automatically. If the short circuit is removed at this point, the load will be transferred back to the
inverter. The transfer is determined by the features of the protective device of the system.
In the above two situations, the UPS screen will display alarm messages.
For parallel system, the control logic system constantly monitors load requirements and controls the power supplied by each
UPS module. If an overload condition is sustained for greater than a preset time, the load will transfer to the bypass, when the
number of active modules is unable to satisfy load requirements. The load returns to the inverter if the power is reduced to a
value that can be sustained by the number of active modules in the system.
Maintenance bypass
The UPS has a second bypass circuit, that is maintenance bypass (no switch model), which provides a safe working
environment for the engineers to provide regular maintenance or repair to the UPS system and at the same time provide
unregulated mains supply to the loads. The maintenance bypass can be manually selected through the maintenance bypass
switch, and it can be disconnected by turning the switch to OFF.
NOTE: If the UPS system has 2 or more UPS modules and when the load capacity exceeds the single module capacity,
do not use the internal maintenance bypass switch an external maintenance bypass breaker should be used instead.
2.2.4 UPS power supply switch configuration
The available configurations are:
•The UPS without any switch.
•The UPS equipped with single switch: maintenance bypass switch Q3.
•The UPS equipped with four switches:
•Rectifier input switch Q1.
•Bypass input switch Q2.
•Maintenance bypass switch Q3.
•Output switch Q5.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

The block diagram of the UPS module are shown in Figure 2.4 below, Figure 2.5 on the next page and Figure 2.6 on page13.
The UPS has split bypass configuration (the bypass adopts independent mains input) and common input configuration. In
split bypass configuration, the static bypass and maintenance bypass share the same independent bypass power supply.
Where a separate power source is not available, the input supply connections of the bypass input switch Q2 and rectifier input
switch Q1 would be linked together to make the bypass input and rectifier input use mains power of the same route.
During the normal operation of the UPS, except for the maintenance bypass switch Q3, other switches must be closed.
Figure 2.4 UPS Power Supply Switch Configuration Without Switch
Item Description Item Description
1 Bypass input 8 Inverter
2 Shorting copper bar of input configuration 9 Automatic Inverter switch
3 Static switch 10 Battery charger/discharger
4 UPS 11 UPS output
5 Mains input 12 Neutral line input
6 Rectifier 13 Battery
7 DC bus 14 BCB
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual

Figure 2.5 UPS Power Supply Switch Configuration Single Switch
Item Description Item Description
1 Bypass input 9 Inverter
2 Maintenance bypass switch Q3 10 Automatic Inverter switch
3 Static switch 11 Battery charger/discharger
4 UPS 12 UPS output
5 Shorting copper bar of input configuration 13 Neutral line input
6 Mains input 14 Battery
7 Rectifier 15 BCB
8 DC bus
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual