Always On GES-153NX User manual

M0703_NX_Series_Operators_Manual V1.25 2012-06-12
NX-Series
Three Phase UPS System
GES-103NX – GES-1603NX
10 kVA – 160 kVA
Operators Manual

Always On UPS Systems
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Always On UPS Systems
M0703_NX_Series_Operators_Manual V1.25 2012-06-12 ii
Dear Customer,
We Thank You for selecting our NX Series UPS
system as your power quality solution, and we are
pleased to include you as one of our valued
customers at Always On UPS Systems Inc.
We are confident that this Always On NX Series
Uninterruptible Power Supply system, developed and
manufactured in our ISO 9001 Certified facilities will
provide the quality and satisfaction you demand.
Please read the Operators Manual carefully as it
contains the necessary information required to extend
the life of this UPS to its fullest and this manual will
also inform you as to how to use this UPS.
Thank you for choosing us.
We Are Always On!

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Preface
Congratulations on your choice of NX Series Uninterruptible Power Supply (UPS). This system will
protect your valuable equipment from the electrical noise, spikes, surges and other power
aberrations found in today’s power grids.
This manual describes how to prepare the installation site and procedures for moving, installing
and connecting the UPS, with detailed information of maintenance procedures suggested to allow
for maximum reliability.
It will also explain the function of the UPS module, the purpose and location of the switches, the
meaning of system events identified on the front LCD panel and provides procedures for starting
and stopping the UPS.
While every care has been taken to ensure the completeness and accuracy of this manual, Always
On UPS Systems Inc assume no responsibility or liability for any losses or damages resulting from
the use of the information contained in this document.
WARNING!
Installation restrictions or additional measures may be needed to prevent specific disturbances.
Ensure all local and national electrical codes are followed during installation and connection. The
information contained in this manual is to be used as a guideline and recommendation only.
We recommend that this manual be kept with the UPS (Holder provided inside the front door) for
future reference. If any problems are encountered with the procedures contained in this manual,
please contact our Service Center before proceeding.
This document shall not be copied or reproduced without the explicit written permission of Always
On UPS Systems Inc.
Due to technical advancements and improvements, some of the information contained in this
manual may be changed or modified without prior notice.
Safety Instructions
Read the safety instructions contained on the following pages carefully before the installation, start-
up of the UPS its options and batteries. Also refer to this manual before any maintenance
procedures are undertaken
Please pay particular attention to the text in the rectangular boxes as below:
They contain important information or warnings concerning electrical connections and personnel
safety.

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TABLE OF CONTENTS
1IMPORTANT SAFETY INSTRUCTIONS..................................................................................1
2INTRODUCTION.......................................................................................................................3
2.1 System Description.........................................................................................................................3
2.2 Definitions........................................................................................................................................3
3THEORY OF OPERATION.......................................................................................................5
3.1 General Topology............................................................................................................................5
3.2 Normal Operation Mode..................................................................................................................6
3.3 Back-Up Mode: ................................................................................................................................6
3.4 Reserve Mode:.................................................................................................................................7
3.5 Maintenance Bypass Mode: ...........................................................................................................7
3.6 Features and Advantages...............................................................................................................8
3.7 Rectifier ..........................................................................................................................................10
3.8 Inverter ...........................................................................................................................................11
3.9 Static Switch ..................................................................................................................................12
3.10 Maintenance Bypass Switch ........................................................................................................12
4INTER-PCB DIAGRAM...........................................................................................................13
5DIMENSIONS & DRAWINGS.................................................................................................14
6INSTALLATION......................................................................................................................18
6.1 Transport........................................................................................................................................18
6.2 Delivery...........................................................................................................................................18
6.3 Storage ...........................................................................................................................................19
6.3.1 STORAGE OF THE UPS............................................................................................................19
6.3.2 STORAGE OF BATTERY...........................................................................................................19
6.4 Site & Environment Consideration..............................................................................................20
6.5 Unpacking ......................................................................................................................................21
6.6 Cable Selection..............................................................................................................................23
6.6.1 CURRENT RATING FOR INPUT ...............................................................................................23
6.6.2 CABLE SIZE FOR INPUT & OUTPUT .......................................................................................23
6.6.3 FUSE RATING & CABLE SIZE FOR BATTERY BANKS...........................................................27
6.7 Terminal Connection.....................................................................................................................28
7FRONT PANEL.......................................................................................................................29
8OPERATION...........................................................................................................................34
8.1 Switch On Procedure (Authorized Trained Personnel ONLY) ..................................................34
8.2 Shutdown Procedure ....................................................................................................................35
8.3 From Inverter To Manual Bypass Procedure..............................................................................36
8.4 From Manual Bypass To Inverter Procedure..............................................................................37
9THE LCD DISPLAY ................................................................................................................38
9.1 Menu 0 – Main Menu .....................................................................................................................38
9.2 Menu 1 – Select Menu ...................................................................................................................39
9.3 Menu 2 – Status Warning Menu ...................................................................................................40

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9.4 Menu 3 – Real Time Data Menu....................................................................................................41
9.5 Menu 4 – Historical Event Menu ..................................................................................................42
9.6 Menu 5 – Parameter Setting Menu...............................................................................................43
9.7 Menu 6 – Rectifier Data Menu ......................................................................................................44
9.8 Menu 7 – Reserve Data Menu.......................................................................................................44
9.9 Menu 8 – Output Data Menu.........................................................................................................45
9.10 Menu 9 – Other Data Menu ...........................................................................................................45
9.11 Menu 10 – Boost Charge Setting Menu.......................................................................................46
9.12 Menu 11 – Data Time Setting Menu .............................................................................................48
9.13 Menu 12 – Other Setting Menu.....................................................................................................48
10 INTERFACE CONNECTIONS ................................................................................................49
10.1 Dry Contacts ..................................................................................................................................49
10.2 Software for PC Monitoring..........................................................................................................50
10.3 Emergency Power Off Connection ..............................................................................................50
10.4 DB9 Connectors ............................................................................................................................50
10.5 Web Monitoring Module (SNMP Module) ....................................................................................50
11 OPTIONS ................................................................................................................................51
11.1 Battery Cabinet..............................................................................................................................51
11.2 Battery Runtime Charts ................................................................................................................52
11.3 Emergency Stop Switch ...............................................................................................................53
11.4 Remote Display Panel...................................................................................................................53
11.5 Isolated Parallel Redundant Operation (IPRO)...........................................................................53
11.6 12-Pulse Rectifier ..........................................................................................................................53
11.7 5th Harmonic Filter.........................................................................................................................53
11.8 External Wrap Around Bypass ....................................................................................................53
12 TECHNICAL SPECIFICATION...............................................................................................54
12.1 NX Series – 10kVA to 60kVA UPS 3Ø Input................................................................................54
13 CONTACT INFORMATION..................................................................................................... 60

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1 IMPORTANT SAFETY INSTRUCTIONS
READ AND FOLLOW ALL SAFETY INSTRUCTIONS.
SAVE THESE INSTRUCTIONS.
This manual contains important safety instructions that should be followed during installation and
maintenance of the NX Series UPS system and optional packages. Before the installation process
begins, we recommend that the installer read through the safety precautions, operators manual
and the option installation instructions, taking all necessary safety precautions to protect
themselves and the equipment being installed.
GENERAL
-Move the UPS in an upright position, in its original packaging, to its final destination.
To lift the cabinets, use a forklift or lifting belts with spreader bars.
- Check for sufficient floor and elevator loading capacity.
- Check the integrity of the UPS equipment carefully.
If visible damage is evident, do not attempt to install or start the UPS. Contact the transport
delivery company immediately, file a claim with the transport company and inform Always On
directly.
- Do not use outdoors
- The use of accessory equipment not recommended by Always On may cause an unsafe
condition
- WARNING! RISK OF ELECTRICAL SHOCK: use extreme caution when removing covers.
- All maintenance and service work should be performed by qualified and trained service
personnel. The UPS may contain its own energy source, (batteries) which can be dangerous to
the untrained person. This UPS contains potentially hazardous voltages
- The field-wiring terminals may be electrically live, even when the UPS is not connected to the
utility.
- Use caution when servicing batteries. A battery can present a risk of electrical shock, burn from
high short-current. Battery acid can cause burns to skin and eyes. If acid is spilled on skin or in
eyes, flush with fresh water and contact physician immediately.
- When replacing batteries use the same number and type (sealed-cell lead acid).
- Proper disposal of batteries is required. Refer to your local codes for disposal requirements.
- Dangerous voltages may be present during battery operation. The batteries must be
disconnected during maintenance or service work. (Open battery breaker of fuses)
- Be aware that the inverter can restart automatically after the utility voltage is restored.
- Do not use this equipment for other than intended use.

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INSTALLATION
-This UPS is intended for use in a controlled indoor environment free of conductive
contaminants and protected against any type of intrusion.
-Do not install the UPS in an excessively humid environment or near water.
-Avoid spilling liquids and/or dropping any foreign object(s) onto the UPS.
-The unit must be placed in a sufficiently ventilated area; the ambient temperature should not
exceed 40°C (104°F).
-Optimal battery life is obtained if the ambient temperature does not exceed 25°C (77°F).
-HIGH GROUND LEAKAGE CURRENT: ground connection completed before connecting the
AC voltage wires on the input!
-Switching OFF the UPS does not isolate the UPS from the utility as the utility supply is still HOT
at the input terminal strip. Supply breaker needs to be opened.
-It is important that air can move freely around and through the unit. Do not block the air vents.
-Avoid locations in direct sunlight or near heat sources (gas or electric heaters).
STORAGE
-Store the UPS in a dry location free of contaminants;
-Storage temperature must be within -25°C (-13°F) to 55°C (131°F).
- If the unit is stored for a period exceeding 3 months, the batteries must be recharged
periodically (time depending on storage temperature).
WARNING!
LETHAL VOLTAGES MAY BE PRESENT WITHIN THIS UNIT EVEN WHEN IT IS APPARENTLY
NOT OPERATING. OBSERVE ALL CAUTIONS AND WARNINGS IN THIS MANUAL. FAILURE
TO DO SO COULD RESULT IN SERIOUS INJURY OR DEATH. REFER UNIT TO QUALIFIED
SERVICE PERSONNEL IF MAINTENANCE IS REQUIRED. NO ONE SHOULD WORK ON THIS
EQUIPMENT UNLESS THEY ARE FULLY QUALIFIED TO DO SO. AN INSTALLER SHOULD
NEVER WORK ALONE.
WARNING!
WHEN REMOVING POWER FROM THE UPS, ALLOW FIVE MINUTES FOR CAPACITORS TO
DISCHARGE BEFORE WORKING ON THE EQUIPMENT.
CAUTION!
This equipment complies with the requirements in Part 15 of FCC rules for a Class A
computing device. Operation of this equipment in a residential area may cause interference
to radio and TV reception, requiring the operator to take whatever steps necessary to
correct the interference.
CAUTION!
Do not put option control wiring in the same conduit as the UPS input or output power
cables.
READ AND FOLLOW ALL SAFETY INSTRUCTIONS.
SAVE THESE INSTRUCTIONS.

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2 INTRODUCTION
2.1 System Description
The NX Series (UPS) continually monitors and provides conditioning to the incoming electrical
power removing surges, spikes, sags, over-voltages, and other irregularities that are inherent in
commercial utility power. This UPS system supplies clean, consistent power at the rated
voltage with low wave distortion to your sensitive electronic equipment. Blackouts, brownouts
and other power interruptions regardless of duration can be protected against with additional
optional battery cabinets to provide the necessary emergency power to safeguard your
operation.
Always On UPS Systems Inc. believes that product reliability is first and foremost in acquiring
the confidence of the industry. Our Quality Control Standards ensures that testing at the
component level, board level, function level and completed stage level as specified by our
ISO9001 Certification allows us to gain this confidence and sets us apart as one of the leading
UPS manufacturers in this industry.
Always On maintains reliability by incorporating conservatively rated components minimizing
transfers to bypass, which eliminates over working many components. Always On provides a
truly isolated output (no common neutral from input to output) to eliminate all types of power
aberrations as well as Common and Normal Mode noise increasing the reliability and life of the
loads connected.
2.2 Definitions
UPS Module: That portion of the UPS system which contains the rectifier/charger, inverter,
static bypass switch, maintenance bypass switch, controls, monitoring, and indicators.
Rectifier/Charger: That portion of the UPS module, which converts the normal source AC
input power to DC power for the inverter input and for charging the battery.
Inverter: That portion of the UPS module, which converts DC bus power to regulated and filter
AC power that is then supplied to the critical loads.
Static Bypass Switch: That portion of the UPS module which automatically transfers the
critical loads, without interruption, from the inverter output to the bypass AC power source in
the event of an overload or degradation of the inverter’s performance.
Maintenance Bypass Switch: That portion of the UPS module which is used to connect the
bypass AC power source to the critical loads while electrically isolating the static bypass switch,
rectifier/charger and inverter for maintenance purposes.
Battery: The battery system provides DC power to the inverter input when the normal AC input
power to the UPS fails or in the event that the rectifier/charger failure.
Critical Loads: These are loads that require clean, regulated and continuous AC power and
which are connected to the output of the UPS module.

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Key features:
¾0.9 power factor, the Always On NX Series delivers more real power than other
manufactured UPS’s. With today’s trend toward power factor corrected loads, the NX
Series can support more total load than any other UPS, of similar size, allowing you
to support a greater number of today’s Power Factor Corrected (PFC) equipment.
¾Isolated Parallel Redundancy Operation (IPRO) is exclusive Always On technology.
With IPRO the NX Series UPS’s are controlled in a true peer-to-peer configuration
where all critical elements and functions (including bypass) being redundant. The NX
Series is designed to be the most reliable power protection system available on the
market today.
¾IGBT technology and new triggering technology allows the NX Series to offer
efficiencies up to 94%.
¾Digital Signal Processor (DSP), Flash memory and user compatibility are the
technology corner stones of our New Age of power quality and reliability.
¾Custom made power protection and tailored to meet your individual requirements,
the NX Series offers user selectable options. I.e. Input harmonic filters,
comprehensive shutdown software suite for mission control and data protection
needed to facilitate all your needs.

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3 THEORY OF OPERATION
3.1 General Topology
UPS Module Components: The UPS module consists of the following major components:
-Input, Reserve and Bypass circuit breakers
-Rectifier / Charger
-Inverter
-Microprocessor controlled logic and control panel with alarm indicators and digital
metering display
-External battery connection
-Static bypass
-Full maintenance bypass
-Emergency power off (EPO) connection
-Communications interface
-Input power walk-in
-Front cable connections
-Output isolation transformer
-Optional Features:
-5
th harmonic filter to reduce input harmonic content.
-SNMP Adapter for network communications and monitoring
-Additional battery modules for extended runtime
-Top cable entry
-Remote display panel
-Emergency power off switch
-External maintenance bypass cabinet
-Isolated parallel redundant operation (IPRO)
Generally, there are four modes of operation for a UPS system, NORMAL MODE, BACK-UP
(BATTERY) MODE, RESERVE MODE and MAINTENANCE BYPASS MODE.
Figure 3.1.1
General Block Diagram

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3.2 Normal Operation Mode
The rectifier/charger converts the supplied
AC power into DC (bus) power, which is then supplied to the inverter and the battery charger.
The DC to AC inverter then supplies continuous, noise free AC power to the critical loads. The
inverter output is synchronized with the bypass AC power source provided that the bypass AC
power source is within the specified frequency range.
3.3 Back-Up Mode:
As the batteries are connected to the DC bus they supply energy to the inverter via this DC
bus, the AC power will remain constant and continuous without interruption to the loads when
the AC fails or falls out side of the operating parameters. Upon return of the supplied AC input
power the UPS the rectifier will automatically assume the DC load (charger, inverter) from the
batteries. The UPS will simultaneously supply power to the inverter and the battery charger to
replenish the batteries.
Figure 3.2.1
Normal Mode Operation
Figure 3.3.1
Back-up Mode Operation

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3.4 Reserve Mode:
If the inverter is placed into an abnormal condition, such as over temperature, short circuit,
abnormal output voltage or is overloaded for a period which exceeds the inverter’s limits, the
inverter will automatically shutdown in order to protect itself. If the AC utility power is within the
normal parameters, the static switch will automatically transfer the load to the reserve (utility)
source without interruption of the AC output.
3.5 Maintenance Bypass Mode:
During UPS maintenance procedures or battery replacement, the loads cannot be interrupted,
and as such the technician needs to turn off the inverter switch, close the bypass breaker and
then open the rectifier and reserve (utility) breakers. The UPS is now running in Maintenance
By-pass mode supplying utility AC to the loads. The AC output will not be interrupted during the
manual bypass transfer procedure because the maintenance bypass switch is designed to
supply continuous power to the loads.
Figure 3.4.1
Reserve Mode Operation
Figure 3.5.1
Maintenance (Manual) Bypass Mode Operation

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3.6 Features and Advantages
a. Reliable input protection: Circuit breakers are in each input loop to ensure power can
continue through the other loops in the event of a breaker trip caused by abnormal conditions
in either the rectifier or the load.
b. Input surge protection: Input surge protection is added at the input to provide enhanced
protection to both the UPS and the load and also protects against lightning effects and/or
surges caused by large cycling loads or those that are being turned on and/or off.
c. EMI suppression: An EMI filter is added to meet the international EMC limits to ensure that
No noise will effect or interfere with other equipment connected to the same AC source.
d. Ruggedness: The rectifier employs phase control technology to regulate the DC bus
voltage allowing the batteries to be charged while supplying DC power to the inverter. This has
been proven to be the most efficient method to control and regulate the charge on the
batteries. The SCR technology and PFC circuit also assist in maintaining the input waveform.
e. High frequency design: The inverter design incorporates high frequency, highly efficiency
Insulated Gate Bi-polar Transistors (IGBT). A PWM wave, synchronized to the bypass input,
triggers the IGBT’s, which invert the DC into AC power required by the loads. This design
decreases the number of required components, increases reliability and performance while
decreasing acoustic noise, size and weight.
f. True galvanic isolation: The isolation transformer addresses ground differentials between
the input and output, and prevents ground leakage current problems, common mode and
normal mode noise. This transformer is located on the output side of the UPS system providing
isolation under every mode of operation.
g. PNP modular design: The circuit boards are designed into several modules, which are
plugged into slots in the UPS. These plug-able modules allow for easy replacement in the field
when necessary and eliminate field diagnostics.
h. Cold start function: The UPS can be started without the utility AC supply being activated.
Or present at the input terminal strip because our designed system is designed with current
limiting circuitry, which allows Startup of the UPS on battery DC power.
i. Multi-CPU design: Several CPU’s are designed into the control circuit. These critical
functions are designed with multi-level redundancy increasing reliability and up-times by
eliminating field problems.
j. Protection against possible operator error: The UPS is designed with breaker on/off
sensors and power supply sensors. These sensors prevent potential operational mistakes from
interfering with the start –up operation causing possible damage.
k. Wide input range: The components are overrated by designed to handle high input
voltages and currents without harm to the system, ensuring that Always On UPS’s remain one
of the most reliable UPS Systems available in today’s market.
l. Harsh environment: Each component of the UPS is chosen with the highest degree of
safety margins allowing for wider environmental parameters and specifications related to
temperature, humidity, altitude, surge or noise.

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m. Intelligent charger: The UPS will automatically recharge (boost charge) the batteries when
the battery voltage level decreases to approximately 2V/Cell or to a user specified level. To
prevent the over-charging of the battery, the boost charge will stop when batteries achieve a
90% charged level or the ambient temperature reaches 35oC (95oF) at which point the float
charging begins.
n. Intelligent battery test: The batteries are tested after every boost charge whether the
charge has been initiated by a battery discharge state (2V/Cell) or by the regular battery test
preformed by the UPS (monthly test). When an abnormal condition (low charge rating, or bad
battery) is found the user will be informed immediately through alarms on the UPS system.
o. Charging rate: The charging rate is selectable (L/M/H) according to Ah ratings of the
batteries. The charger is designed to charge the larger battery banks without adding an
additional charger (up to 8hr. back-up).
p. MTBF of cooling fans: Long cycling fans will operate at variable speeds necessary which is
dependent on the ambient temperature of the UPS system increasing the life expectancy of the
fan motors.
q. Redundant power supply: Redundant power supplies have been installed to allow for
worry free operation of the system.
r. Intelligent interface: One remote control panel (or one PC) can monitor and control up to
ninety-nine UPS’s. The communication allows for N+1 redundancy, whereby if one system
encounters an emergency or fault condition, it will warn the user immediately and the load is
automatically transferred to the other UPS systems. The UPS status, data or commands are
transmitted to external modules through four RS-485 ports.
s. Data log capability: All abnormal conditions will be stored within the UPS control interface
board for further reference by the user. Each abnormal condition is time and date stamped
(real-time clock) as the event occurs. This history is stored and cannot be removed even if or
when the UPS is turned off for servicing.
t. Convenient front panel design: The LCD display and control switches are accessible
through the up, down, and enter switches below the front panel window. All the viewable
parameters can be read without opening the front door. The inverter on/off switch is protected
from accidental operation by being located behind the locked front door although the inverter
can still be switched on and off via the control switches on the front panel but this feature is
password protected.
u. Emergency stop: In the event of an emergency the UPS can be shutdown (no AC at the
output) either through a switch (optional) or through a smoke detector signal (optional).

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3.7 Rectifier
The main function of a rectifier is to convert the AC input power to DC power. The DC power is
then used to charge the batteries, supply the DC bus, which in turn supplies the inverter.
The rectifier design used in the 10kVA to 60kVA UPS’s include a 6-pulse full controlled rectifier.
Power Factor Correction (PFC) has been added to maintain a high input power factor,
independent of the load power factor. This 6 pulse rectifier smoothes the current waveform and
reduces the harmonic content reflected back to the utility. The control circuit regulates the DC
bus to within 1% of the nominal voltage. Soft walk-in circuitry (approximately 20 seconds) and
current limiting circuitry are used to prevent over current or surge currents from affecting any
part of the UPS system.
Additionally, over and under-voltage protection is added to improve reliability and to shutdown
the rectifier in the event of abnormal conditions. The DC bus is adjustable to allow for different
types and capacities of batteries. The power components used within the rectifier are specially
designed and selected to handle extreme ranges of high voltage and high current (–25% to
+25%).
In order to further improve the power factor and reduce harmonic current drawn by the rectifier,
Always On UPS’s above 80kVA incorporate a 12-pulse full controlled rectifier (also available as
an option on the 10 to 60kVA UPS’s) to reduce the total harmonic current to less than 12%. A
phase shift transformer is added with input inductors to achieve this higher level of
performance while maintaining our high input power factor. An optional 5th harmonic filter can
be added to further reduce the total harmonic distortion current to less than 9%.
The total harmonic current can be decreased to less than 7% with the inclusion of the 18-pulse
full controlled rectifier. This option is recommended for the larger (80kVA and up) UPS systems.

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3.8 Inverter
The inverter is composed of IGBT’s, inductors, capacitors, highly efficient filters, control
circuitry and protection circuitry. This inverter inverts the DC power received on the DC bus to
isolated, noise-free AC power, which is then supplied to the critical loads. Our PWM wave
generator is switching at a higher frequency well above the human audible range.
The Voltage regulating circuitry limits the output voltage variation to within 1% of the nominal
voltage and special compensation circuitry has been added to eliminate output distortion.
Every component is oversized to accept a wide DC input range (from 285 to 420VDC), allowing
the output waveform to remain sinusoidal throughout the entire range. With the aid of dynamic
feedback loop circuits the inverter maintains a true sine wave output, even if non-linear loads
are connected.
The system is designed and incorporates an independent inverter per phase. These inverters
are totally independent of each other preventing the possibility of cascading failures while
allowing the user to connect loads to adjacent inverters without affecting the other inverters.
This connectivity provides high-end voltage regulation under a 100% unbalanced load
situation.
The IGBT is operated in its optimal condition to obtain maximum efficiency, keeping electrical
costs to a minimum.
Usually, most UPS failures are a result of inverter failures. To prevent this occurrence, Always
On has included redundant protection circuitry to protect the inverter and increase its reliability.
To enhance this protection we have also added a high efficiency filter designed to suppress the
spikes and noise that can be reflected from the attached loads back into the UPS system.
Specifying oversized and high quality components, additional semi-conductor fuses and
allowing for good ventilation systems within further increase reliability.
Figure 3.8.1
Inverter Layout

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3.9 Static Switch
The static switch is composed of two pairs of back to back naturally commutated SCR’s, which
moves the load from inverter to reserve (utility) or from reserve to inverter without interruption
of power to the load.
Detection circuitry is included in the control circuit to achieve “0” dead time transfer. Additional
detection is employed to control the static switch transfer.
Dead Short: If a dead short circuit was to occur under normal mode operation, the UPS would
detect the short circuit and immediately stop the inverter until the problem has been rectified.
Due to the large amount of current a dead short requires, the static switch will not transfer to
reserve preventing the tripping of the reserve breaker.
Overload condition: The UPS will transfer the load to reserve (utility) path. The static switch is
designed to handle 110% of the capacity of the system but will switch to the reserve path if the
overload continues for any length of time. The load will still be operational, but the load system
will not be protected from a utility failure, as it has no battery capability until the overload is
removed.
The static switch will only be activated if the input levels are within parameters to ensure the
load is only supplied with acceptable power to protect against damage that may be caused to
the critical load. The system performs numerous checks on the transfer from inverter to
bypass and visa versa to ensure the exchange is smooth.
3.10 Maintenance Bypass Switch
The maintenance bypass switch is a function of Always On UPS’s, which is open under normal
operation, and closed for maintenance service. All power supplied to the UPS should be
disconnected before service begins. The maintenance bypass is switched seamlessly to
supply utility AC power to the loads during UPS maintenance and servicing. If the bypass
breaker is closed (by mistake) under normal operations, the inverter will stop and the load will
be transferred to reserve (utility) power.
The inverter cannot be turned on when the maintenance bypass breaker is in the closed
position.
(The operation of the maintenance bypass breaker is explained later in this manual)
Figure 3.9.1
Static Bypass

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4 INTER-PCB DIAGRAM
Rectifier
Driver
Rectifier
Control
Rectifier
Driver
Rectifier
Control
Switch
LED
Display
Controller
Power Supply
Batt
Relay
SS Drive
R Phase
S Phase
T Phase
Inverter
Driver
Inverter
Driver
Inverter
Driver
Call
Service
Remote Control
Panel
PC
Communications
SNMP (Web)
Monitoring
Battery Monitoring
LCD
Optional Communication
Features
6 Pulse Rectifier
12 Pulse Rectifier
Dry
Contact
Figure 4.1
Block Diagram For Component And Feature Layout

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5 DIMENSIONS & DRAWINGS
559mm [22”]
815mm [32"]
1600mm [63"]
95mm [3 3/4"]
Figure 5.1
10kVA to 60kVA Dimensional Drawing