Vertiv Liebert APM Plus User manual

Vertiv™ Liebert® APM Plus
User Manual
50-250 kVA UPS

Vertiv™ | Liebert® APM Plus User Manual
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
taken to ensure the accuracy and completeness of this document, Vertiv
assumes no responsibility and disclaims all liability for damages resulting from
use of this information or for any errors or omissions. Refer to other local
practices or building codes as applicable for the correct methods, tools, and
materials to be used in performing procedures not specifically described in this
document.
The products covered by this instruction manual are manufactured and/or sold
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Vertiv™ Liebert® APM Plus User Manual

TABLE OF CONTENTS
1 Im portan t Safety In structions 1
2 O verview 2
2.1 Features 2
2.2 Design Concept 2
2.2.1 System Design 2
2.2.2 Bypass 4
2.2.3 System Control Principle 4
2.2.4 UPS Power Supply Switch Configuration 5
2.2.5 Battery Circuit Breaker (BCB) 6
2.3 Parallel System 7
2.3.1 Parallel System Features 7
2.3.2 Parallel System Requirements 7
2.4 Operation Modes 8
2.5 Battery Management 15
2.5.1 Normal Function 15
2.5.2 Advanced Function 16
2.5.3 Battery Temperature Compensation 17
2.6 Battery Protection 17
3 M echanical Installation 18
3.1 Precautions 18
3.2 Transportation 19
3.3 Tools 19
3.4 Unpacking 21
3.5 Initial Inspection 23
3.6 Environmental Requirement 24
3.6.1 UPS Location Selection 24
3.6.2 Battery Location Selection 24
3.6.3 Storage 24
3.7 Mechanical Requirement 25
3.7.1 Composition 25
3.7.2 Moving Cabinet 25
3.7.3 Clearance 25
3.7.4 Cable Access Mode 25
3.8 Installation Drawings 26
4 Electrical Installation 28
4.1 Wiring of Power Cable 28
4.1.1 System Configuration 28
4.1.2 Maximum Steady State AC and DC Currents 29
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4.1.3 Recommended CSA of UPS Cable 29
4.1.4 Selection of UPS I/O Switch 29
4.1.5 Distance between the UPS Connection Point and Floor 30
4.1.6 Notes 30
4.1.7 Power Cable Connecting Terminal 30
4.1.8 Protection Ground 30
4.1.9 External Protective Device 31
4.1.10 Power Cable Connection Steps 32
4.2 Wiring of Signal Cable 37
4.2.1 Overview 37
4.2.2 Dry Contact Port J6 38
4.2.3 Dry Contact Port J7 39
4.2.4 Dry Contact Port J8 42
4.2.5 REPO Port 43
4.2.6 Host Communication Port 44
4.2.7 Parallel and LBS Communication Ports 44
4.2.8 Intellislot Port 44
4.2.9 Signal Cable Connection Steps 45
5 O p era tor C o ntro l an d D is play P an el 4 8
5.1 Introduction 48
5.2 Navigating through the Liebert APM Plus Touchscreen Control Panel 49
5.2.1 Access Level Log-In 49
5.2.2 Liebert APM Plus Touchscreen Control Panel Components 50
5.3 Operation 56
5.3.1 Log In to the Liebert APM Plus Touchscreen Control Panel 56
5.3.2 Customizing the Display 57
5.3.3 Operator Controls 64
5.4 Viewing UPS Status 71
5.4.1 Viewing UPS Data with the Status Gauge 71
5.4.2 Viewing UPS Data with the Status Panel 75
5.4.3 Logs—Alarms and Events 80
5.5 Viewing UPS Component Status 82
5.6 Status Bar Component 85
5.6.1 Status Bar Messages 85
5.7 Alarm List 89
6 S ing le U P S O p era tion Intro du ctio n 9 4
6.1 Brief Introduction 94
6.1.1 Precautions 94
6.1.2 Power Switch 95
6.2 UPS Startup Procedures 96
6.2.1 Startup Procedures in Normal Mode 96
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6.2.2 Startup Procedures in ECO Mode 100
6.2.3 Startup Procedures in Battery Mode (Battery Cold Start) 101
6.3 Procedures for Transfer Between Operation Modes 102
6.3.1 Transfer from Normal Mode to Battery Mode 102
6.3.2 Transfer from Normal Mode to Bypass Mode 102
6.3.3 Transfer from Bypass Mode to Normal Mode 102
6.3.4 Transfer from Normal Mode to Maintenance Mode 103
6.3.5 Transfer from Maintenance Mode to Normal Mode 104
6.4 Battery Test Procedures 105
6.5 UPS Shutdown Procedures 107
6.5.1 Procedures for Completely Powering Down UPS 107
6.5.2 Procedures for Completely Powering Down UPS while Maintaining Power to Load 107
6.6 EPO Procedures 108
6.7 UPS Reset Procedures after EPO 108
6.8 Automatic Restart 108
6.9 Selecting Language 109
6.10 Changing Current Date and Time 110
6.11 Control Password 111
7 Battery 112
7.1 Introduction 112
7.2 Safety 112
7.3 UPS Battery 114
7.4 Precautions for Installation Design 114
7.5 Battery Installation Environment and Number of Batteries 115
7.5.1 Installation Environment 115
7.5.2 Number of Batteries 116
7.6 Battery Protection 116
7.7 Battery Installation and Connection 117
7.7.1 Battery Installation 117
7.7.2 Battery Connection 117
7.8 Design of Battery Room 119
7.9 Common Battery String 120
7.10 BCB Cabinet (Optional)- Applicable for APAC Region 121
7.11 Battery Temperature Sensor (Optional) 124
7.12 Battery Ground Fault Detector (Optional)- Applicable for APAC Region 124
7.13 BCB Reference Current and Connection 125
7.14 Battery Maintenance 126
7.15 Disposal of Used Battery 126
8 Parallel S ystem and LB S System 128
8.1 General 128
8.2 System Installation Procedures 128
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8.2.1 Preliminary Checks 128
8.2.2 Cabinet Installation 128
8.2.3 External Protective Device 130
8.2.4 Power Cable 130
8.2.5 Parallel Cable 131
8.2.6 Remote EPO 132
8.3 Operation Procedures for Parallel System 133
8.3.1 Startup Procedures in Normal Mode 133
8.3.2 Maintenance Bypass Procedures 133
8.3.3 Procedures for Isolating One UPS module from Parallel System 134
8.3.4 Procedures for Inserting One Isolated UPS module in Parallel System 135
8.3.5 Procedures for Completely Powering Down UPS 136
8.4 LBS System 136
8.4.1 Cabinet Installation 136
8.4.2 External Protective Device 139
8.4.3 Power Cable 139
8.4.4 LBS Cable 139
9 O p tion s 14 2
9.1 Option List 142
9.2 Option Introduction 143
9.2.1 Optional Side Cabinet 143
9.2.2 Battery Temperature Sensor Kit 146
9.2.3 Battery Ground Fault Kit- Applicable for APAC Region 147
9.2.4 Bypass Short-circuit Withstand Option 147
9.2.5 Seismic Anchor Kit 148
9.2.6 IS-UNITY-DP Card 151
9.2.7 IS-UNITY-LIFE 151
9.2.8 SIC Card- Applicable for APAC Region 152
9.2.9 IS-Relay Card 153
9.2.10 UF-RS485 Card- Applicable for APAC Region 155
9.2.11 Parallel Cable 156
9.2.12 LBS Cable 156
9.2.13 BCB Cabinet- Applicable for APAC Region 156
9.2.14 Back-feed Contactor Option 157
9.2.15 Top Fan Assembly 158
9.2.16 I/O Switch Assembly 159
9.2.17 IP21 Option 160
9.2.18 IP31 Option 161
9.2.19 LBS Adapter 162
10 C om m un ication 16 4
10.1 SNMP Protocol Communication 164
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Vertiv™ Liebert® APM Plus User Manual

10.2 Modbus Protocol Communication 164
10.3 Dry Contact Communication 165
10.3.1 Communication through IS-Relay Card 165
10.3.2 Communication through Dry Contact Port of Bypass Module 165
11 Service and M aintenance 166
11.1 Safety 166
11.2 Service Procedures of Power Module and Bypass Power Module 166
11.2.1 Notes 166
11.2.2 Service Procedures of Power Module 167
11.2.3 Replacement Procedures of Bypass Power Module 167
11.3 Key Components and Service Life of UPS 168
11.3.1 Life Parameters and the Proposed Replacement Time of Key Components 168
11.3.2 Replacement of Air Filter 169
11.4 Maintenance of UPS and Options 170
12 Specifications 172
12.1 Conformance and Standards 172
12.2 Environmental Characteristics 172
12.3 Mechanical Characteristics 173
12.4 Electrical Characteristics (Input Rectifier) 173
12.5 Electrical Characteristics (Intermediate DC Circuit) 174
12.6 Electrical Characteristics (Inverter Output) 175
12.7 Electrical Characteristics (Bypass Input) 176
12.8 Efficiency and Loss 176
Appendices 178
Appendix A: Glossary 178
Appendix B: Hazardous Substances and Content 179
Appendix C: Disposal After End of Product (Applicable for India) 180
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Vertiv™ Liebert® APM Plus User Manual

1 Important Safety Instructions
Personnel Safety
1. This product must be installed and commissioned by professional engineers of the manufacturer or its
authorized agent. Failure to observe this could result in product malfunction or personnel safety risk.
2. Take time to read this product manual and the safety precaution thoroughly before installing and commissioning
this product. Failure to observe this could result in product malfunction or personnel safety risk.
3. This product is not intended for life support equipment application.
4. Never dispose of the internal or external battery of this product in fire, as it may explode and jeopardize
personnel safety when exposed to flame.
Product Safety
1. If this product will be stored or remain de-energized for a long period, it must be placed in a dry and clean
environment within specified temperature range.
2. This product should be used in an appropriate operating environment. For details, refer to the section on the
environmental requirement in this manual.
3. This product is not designed for application in an environment:
•Where the temperature and relative humidity are outside the specifications
•Subjected to vibrations or shocks
•Where conductive dust, corrosive gases, salts, or flammable gases are present
•Near heat sources or strong electromagnetic interferences.
Disclaimer
Vertiv disclaims any and all responsibility or liability for the defects or malfunction caused by:
•Application range or operating environment outside the specifications
•Unauthorized modification, improper installation or operation
•Force majeure
•Other actions not in compliance with the instructions in this manual.
1 Important Safety Instructions 1
Vertiv™ Liebert® APM Plus User Manual

Safety Precaution
This manual contains information concerning the installation and operation of the Liebert® APM Plus 250 kVA UPS single
module and parallel system. Read this manual thoroughly before installing, using, and servicing the UPS.
W A R N IN G ! T he U P S w ith s tan da rd c on fig uratio n is a c ate go ry C 3 p rod uct fo r co m m e rcial a nd
indu strial app lication in the second env iron m en t. Installation restrictions o r ad ditional
m easu res m ay b e ne ed ed to p reven t d isturbanc es.
IM PO RTA NT ! The U PS ad ding C 2 EM C op tion b ased o n th e stan dard configu ration is a ca teg ory C 2
prod uct for a reside ntial e nv ironm ent o r com m ercial and in du strial app lica tion in th e seco nd
env iron m ent.
Conformity and Standards
This product conforms to the following European directives and UK Regulations:
2014/35/EU
Directive of the council for adapting the legal regulations of member states on electrical equipment for use within specific
voltage limits.
Electrical Equipment (Safety) Regulations: 2016
Regulations implemented according to EU Directive (2014/35/EU) on electrical equipment designed for use within specific
voltage limits approved on the GB market.
2014/30/EU
Directive of the council for adapting the legal regulations of member states on electromagnetic compatibility.
Electromagnetic Compatibility Regulations: 2016
Regulations concerning the aspects on electromagnetic compatibility approved on the GB market.
Conformity is established through compliance with the following standards:
•IEC/EN/BS 62040-1:2008+A1:2013
•IEC/EN/BS 62040-2:2018
Additional information regarding adherence to these directives and regulations is included in the appendices NSR and EMC
to the Declarations of Conformity. If needed, the Declarations of Conformity can be requested to Vertiv.
2011/65/EU
Directive of the council for adapting the legal regulations of member states on the restriction of the use of certain hazardous
substances that can be used in the manufacture of electrical and electronic equipment.
The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment Regulations 2012.
The restriction of the use of certain hazardous substances that can be used in the manufacture of electrical and electronic
equipment approved on the GB market.
1 Important Safety Instructions
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Vertiv™ Liebert® APM Plus User Manual

W A R N IN G ! H ig h e arth lea ka ge cu rre nt
Earth con nection is critical before connec ting the inpu t su pp ly (includ ing b oth m ains supp ly
and b attery).
T his e qu ipm e nt is insta lle d w ith a n E M C filter.
Earth leaka ge cu rrent is less than 30 00 m A .
T ran sien t a nd ste ad y s tate ea rth leak ag e c urre nts , w hich m a y oc cu r w h en th e eq uipm e nt is
started, should be taken into account in the selection of instantan eous RCC B s or R C D devices.
RC CB w hich is sensitive to unidirectional DC pulse (class A ) and insensitive to transient state
curre nt p ulse m ust b e selected .
N ote also that the earth leakage curren ts of the load w ill be carried b y the R C C Bs or RC D s.
The eq uipm ent m u st b e earth ed in acco rdan ce w ith the local electrical cod e of p ractice.
W A R N IN G ! B ac kfe ed ing p rote ctio n
T his U P S is fitte d w ith a d ry con tac t c lo su re s ig na l fo r u se w ith an e xte rn al au tom a tic
disconnect d evice (supplied by others) to protect against b ackfeeding voltage into the
incom ing te rm ina l throu gh the rectifier or b yp ass sta tic sw itch circuit. A lab el m ust be a dd ed
at all ex ternal inc om ing p rim ary supp ly d isconnec t d evice to w arn service perso nn el tha t the
circuit is conn ected to th e U P S. T h e text of the label has th e follow ing m eaning : Risk of
vo lta ge b ac kfee d! Isolate th e U P S, th en c he ck fo r haz ard ou s vo lta ge b etw e en all te rm ina ls
inclu din g th e p rote ctive earth b efore w o rk in g o n th is circ uit.
W A R N IN G ! T he s ele ctio n o f th e u p stre am d istrib utio n p ro tec tion e qu ip m e nt o f th e U P S sh all
b e se lec ted in a cc ord an ce w ith th e loc al electrica l re gu lation s.
W A R N IN G ! U se r se rv ic ea b le c om p on en ts (F or s erv ic e p er so nn el)
A ll equ ip m en t m ainte nan ce an d servicing proce du res involv in g intern al acce ss req uire s the
use of a tool and should be carried out only b y trained personnel. T here are no user-
serv iceab le p arts beh in d co vers req uiring a tool/k ey fo r re m oval.
W A R N IN G ! B atte ry vo lta ge e xce ed s 4 0 0 V d c (F or se rvice p e rso nn el)
A ll ph ysical b attery m ainten ance and se rvicing p roced ures req uires th e use of a tool/k ey an d
should be carried out only by trained personnel.
T ak e sp ec ial care w h en w orkin g w ith th e b atterie s asso cia ted w ith th is U P S. W h en co nn ec ted ,
th e b atte ry term in al vo ltag e w ill e xc ee d 4 00 V d c an d is p ote ntially leth al.
B atte ry m a nufactu rers sup ply d eta ils o f th e n ec es sa ry p rec au tion s to be o bs erve d in w ork ing
on , or in th e vicin ity of, a la rge b an k o f b atte ry cells. T he se p rec au tion s sh ou ld b e fo llo w ed
im plicitly. Particu la r atte ntion sho uld b e paid to th e recom m en da tion s con cernin g loca l
env iron m ental con ditions an d the prov isio n of protective clothin g, first aid a nd fire-figh ting
facilities.
1 Important Safety Instructions 3
Vertiv™ Liebert® APM Plus User Manual

W A R N IN G ! G en era l sa fety (F or u se rs)
Lik e oth er ty pes of larg e p ow e r e qu ipm e nt, th e U P S an d b attery c ircu it b rea ke r b ox /ba ttery
cabinet have hig h voltage inside. As the com ponents w ith h igh voltage can b e accessed only
w hen th e fro nt d oo r is o pene d, the risk o f contacting h ig h voltag e has b een m inim ized. Th is
equipm e nt m eets th e IP2 0 stand ard, an d th e other safe ty sh ield s are provide d inside the
equipm e nt.
T here w ill n ot b e a ny risk w he n o pe ratin g th is eq uipm e nt ac co rdin g to th e ge ne ral
instruc tion s and the step s reco m m end ed in this m a nu al.
W A R N IN G ! M u ltip le p ow e r in pu ts (F or u se rs)
T his U P S sy stem rec eiv es po w er fro m m o re th an o ne s ou rce. D is co nn ectio n o f a ll A C so urc e
and the D C source is required b efore servicing.
T his U P S h as se ve ral c ircu its th at are e nerg ized w ith h ig h A C as w ell a s D C v olta ges. C he ck
fo r v oltag e w ith b oth A C a nd D C vo ltm e ters b efore w o rk in g w ithin th e U P S.
W A R N IN G ! W h en in tern al fu se o f th e U P S is d am a ge d, it m u st b e rep lac ed w ith fu se o f th e
sam e electric pa ram e ters by qualified p erson ne l.
IM PO R TA NT ! T he co m m un ica tion b oa rd is sensitive to electro -static d isc harg e, im p lem ent E SD
preve ntion m easures w hen m an ag ing any c om m u nication b oard .
W A R N IN G ! T he u se r m u st s ele ct a n a pp ro pria te M C C B to p rote ct ag ain st s ho rt circu it a nd
ove rloa d for th e batte ry. W e recom m end u sing V ertiv BC B box to provide a be tter solu tion .
N OT E: Th e U PS m eets the standard require m ent o f sh ort tim e w ithsta nd curren t o f 10 kA . T he
specified upstream fuses are requ ired to obtain the conditional short circuit curren t rating, Icc at 6 5
kA sym m etrica l rm s. It is recom m en de d to select th e fuses in co m plian ce w ith volta ge of 69 0 V ,
cu rren t o f 8 0 0 A an d b rea kin g o f 2 00 k A. T he sp ec ified u pstrea m fu ses s hou ld c om p ly w ith a n IE C
60 26 9 Part 4 standard.
N O T E: B y pas s SC R is o nly p rote cte d a ga inst sh ort c ircu it w h en a de qu ate ca pa city of fu se s/c irc uit
breaker are present in the upstream distribution.
1 Important Safety Instructions
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Vertiv™ Liebert® APM Plus User Manual

The Manual Describes the Equipment
P ro duc t M od el
250 kVA APM 0250kMK16FN02000
1 Important Safety Instructions 5
Vertiv™ Liebert® APM Plus User Manual

Revision Information
V1.0 (December 22, 2021)
Initial release.
V1.1 (April 1, 2021)
Updated Safety precautions; Figure 5-6, 5-11, 5-13, 5-15, 5-21, 5-22, 5-25, 5-26, 5-27, 5-28, 5-29, 5-34, 6-3, 6-5, 6-8, 6-9, 6-11;
Table 12-1, 12-2 and 12-6.
V1.2 (April 20, 2021)
Updated Safety precautions and Table 12-6.
V1.3 (July 18, 2022)
Updated for adding Applicable for APAC Region for selected optional item. Updated Pin J22 to J2 in 7.11 Battery Temperature
Sensor. Updated 2.4 Operation Modes for adding dynamic online mode. Updated table 12.8 Efficiency and Loss.
V1.6 (October 31, 2022)
Updated the manual for GHMI images in Chapter 5 Operator Control and Display Panel. Updated values in Table 7.2 Number
of batteries. Added 28-block battery in Table 7.5 BCB rated current and battery m ax. discharge current at full load
(recommended). Added 9.2.13 LBS Adapter. Updated Table 12.1 European and international standards, Table 12-2
Environmental characteristics, Table 12.3 Mechanical Characteristics, 12.5 Battery, Table 12.6 Inverter output (to critical load),
Table 12.7 Bypass input, and Table 12.8 Efficiency and loss.
1 Important Safety Instructions
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Vertiv™ Liebert® APM Plus User Manual

2 Overview
This chapter briefly introduces the features, design concept, parallel system, operation mode, battery management, and
battery protection of the Liebert® APM Plus 250 kVA UPS (UPS for short).
2.1 Features
UPS is connected between a critical load (e.g. a computer) and mains power to provide high quality power for the loads. UPS
has the following advantages:
•Augment power quality
UPS protects its output against the input power change through the intelligent controller.
•Provide mains failure protection
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 introduces 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). The first stage conversion (AC-DC) adopts three-phase high frequency rectifier to convert the
three-phase input voltage into stable DC bus voltage.
2 Overview 2
Vertiv™ Liebert® APM Plus User Manual

Fig ure 2.1 B lo ck d iag ra m for w o rking p rinc ip le o f U P S s in gle m o du le
N o . D e scrip tio n N o . D e scrip tio n
1 Input 9 Rectifier input switch
2 Output 10 Rectifier
3 Bypass input 11 Inverter
4 Maintenance bypass switch 12 Inverter switch
5 Bypass input switch 13 Output switch
6 Static switch 14 UPS output
7 Maintenance bypass 15 Battery
8 Mains input 16 Battery charger
The UPS has its own battery charger and adopts advanced temperature compensation technology to effectively prolong the
battery service life. The inverter adopts three 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 loads 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 shut down
(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.
2 Overview
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Vertiv™ Liebert® APM Plus User Manual

2.2.2 Bypass
Through the intelligent control of the ‘Static Switch’ module (as shown in Figure 2.1 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 that 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 will
automatically transfer the loads to the bypass.
In normal operating state, to realize 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.
Besides, the UPS has a manual maintenance bypass switch (without switch excluded) for shutdown of the UPS upon
maintenance. In this situation, the bypass will directly supply the critical loads through the maintenance bypass.
N O T E : W hen the load is sup plied by the bypass or m aintenance bypass, the quality of the pow er
su pp ly w ill b e u nc erta in.
2.2.3 System Control Principle
Normal operation
Normal mode: It means that the UPS has normal input mains, the rectifier and inverter operate normally, the load is supplied
by the inverter, the battery circuit breaker is closed, and the battery is in stable floating charge state.
(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 fails 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. During this
period, if the battery voltage falls to the EOD voltage and the mains still has not been recovered, the inverter will stop working
automatically, and the UPS touch screen will display corresponding alarm messages. If the system uses split bypass
configuration and the bypass is normal, the system will transfer to bypass.
Mains recovery
When the mains 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.
Battery disconnection
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 failure, other functions and all the steady state performance of the UPS
will not be affected.
2 Overview 4
Vertiv™ Liebert® APM Plus User Manual

UPS module failure
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, please contact the local customer service center of Vertiv for technical support.
(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 (refer to Table 12.6 on page175) 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 shut down. 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 first of all by the features of the protective device of the system.
In the above two situations, the UPS touch screen will display alarm messages.
(Parallel System) The control logic system constantly monitors load requirements and controls the power supplied by each
UPS module. In the event that 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, i.e. maintenance bypass (without switch excluded), 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.
W A R N IN G ! If th e U P S s ys tem c on sists of tw o o r m o re U P S m o du le s a nd w h en th e loa d
cap acity exceeds the sing le m odu le cap ac ity, d o not use the interna l m ainte nan ce bypass
sw itch .
2.2.4 UPS Power Supply Switch Configuration
The UPS equipped with four switches: rectifier input switch Q1, bypass input switch Q2, maintenance bypass switch Q3, and
output switch Q5. Note that switches Q1, Q2, and Q5 are options of switch group, and the switch group does not support single
switch installation.
Figure 2.2 on the facing page describes the block diagram of the UPS module. The UPS has split bypass configuration (that is,
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 (split
bypass configuration for delivery) 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 shall be closed.
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Vertiv™ Liebert® APM Plus User Manual

Fig ure 2.2 U PS p ow er su pp ly s w itch co nfig uratio n
N o . D e scrip tio n N o . D e scrip tio n
1 Bypass input 10 DC bus
2 Maintenance bypass switch Q3 11 Inverter
3 Bypass input switch Q2 12 Inverter switch
4 Static switch 13 Output switch Q5
5 UPS 14 UPS output
6 Shorting copper bar of input configuration 15 Charger
7 Mains input 16 Neutral line input
8 Rectifier input switch Q1 17 Battery
9 Rectifier 18 BCB
N O T E: Q 1, Q 2 a nd Q 5 a re o ptio nal w hile Q 3 is s tan da rd
N OT E: Th e m ains input an d b yp ass inpu t sh are the sam e n eu tral lin e.
2.2.5 Battery Circuit Breaker (BCB)
The external battery shall be connected to the UPS through the BCB. The BCB cabinet is optional, which shall be installed
near the battery. The BCB is closed manually. The BCB has a shunt tripping coil. When the system is faulty and the BCB
needed to be disconnected, the UPS control circuit will send a signal to the shunt tripping coil so as to trip the BCB. It also has
a magnetic trip facility for overload protection and short circuit protection.
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Vertiv™ Liebert® APM Plus User Manual

2.3 Parallel System
Up to four UPS modules can be parallel-connected to form a parallel system to increase the system capacity and reliability.
The load is equally shared between the paralleled UPS modules.
Moreover, two UPS modules or parallel system can comprise a dual bus system. Each parallel system has independent output.
Output synchronization is achieved through the LBS cable or LBS device, thus enabling seamless load transfer between the
two parallel systems or single modules through the STS device.
2.3.1 Parallel System Features
1. The hardware and software of parallel system are completely the same as those of the single module. The
parallel system configuration is achieved through settings in configuration software.
2. Parallel cables are connected in a ring, providing both system reliability and redundancy.
3. The total load of the parallel system can be queried from each UPS module's TOUCH SCREEN.
2.3.2 Parallel System Requirements
A group of paralleled modules behaves as one large UPS with the advantage of presenting higher reliability. To ensure that all
modules are equally utilized and to comply with relevant wiring rules, the following requirements apply:
1. All UPS modules must be of the same series, and connected to the same bypass source.
2. The bypass and rectifier input sources must be connected to the same neutral line input terminal.
3. Any RCD, if installed, must be of an appropriate setting and located upstream of the common neutral line input
terminal. Alternatively, the device must monitor the protective earth current of the system. Refer to Warning:
High earth leakage current on page3 .
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Vertiv™ Liebert® APM Plus User Manual