KEHUA TECH MY-A Series User manual

User Manual
MY-A Series (10kVA-20kVA) UPS

MY-A Series (10kVA-20kVA) UPS
User Manual
Foreword
i
Foreword
Summaries
Thank you for choosing the Uninterruptible Power System (hereinafter referred to as the "UPS")
product!
This document gives a description of the MY-A series UPS, including the features, performance,
appearance, structure, working principles, installation, operation and maintenance.etc.
Please save the manual after reading, in order to consult it in the future.
The figures in this manual are just for reference, for details please see the actual product.
Suitable Model
MY10-A/MY10-AS/MY10-AT
MY15-A/MY15-AS/MY15-AT
MY20-A/MY20-AS/MY20-AT
Symbol Conventions
The manual quotes the safety symbols, these symbols used to prompt users to comply with safety
matters during installation, operation and maintenance. Safety symbol meaning as follows.
Symbol
Description
Alerts you to a high risk hazard that could exist, if not avoided, result
in serious injury or death.
Alerts you to a medium or low risk hazard that could exist, if not
avoided, result in moderate or minor injury.
Alerts you to a potentially hazardous situation that could exist, if not
avoided, result in equipment damage, data loss, performance
deterioration, or unanticipated results.

Foreword
MY-A Series (10kVA-20kVA) UPS
User Manual
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Symbol
Description
Anti-static prompting.
Be care electric shock prompting.
Provides a tip that may help you solve a problem or save time.
Provides additional information to emphasize or supplement
important points in the main text.
Product standard: Q/ZZKJ 001
Change History
Changes between document issues are cumulative. The latest document issue contains all the changes
made in earlier issues.
Issue 002 (2021-01-15)
Update wiring diagram between UPS and external battery.
Issue 001 (2020-11-19)
First issue.

MY-A Series (10kVA-20kVA) UPS
User Manual
Contents
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Contents
1 Safety Description.........................................................................................................................1
1.1 Safety Announcements.....................................................................................................................................1
1.1.1 Safety Instructions ..................................................................................................................................1
1.1.2 Use Announcements for Battery .............................................................................................................2
1.1.3 Anti-Static Protection..............................................................................................................................3
1.2 Operation and Maintenance Requirements ......................................................................................................3
1.3 Environment Requirements..............................................................................................................................3
2 Overview.........................................................................................................................................5
2.1 Product Intro.....................................................................................................................................................5
2.1.1 Model Meaning.......................................................................................................................................5
2.1.2 Features...................................................................................................................................................6
2.1.3 Appearance..............................................................................................................................................7
2.1.4 Communication.....................................................................................................................................11
2.1.5 Fittings Illustration................................................................................................................................18
2.2 Work Principle................................................................................................................................................18
2.2.1 Work Principle Diagram........................................................................................................................18
2.2.2 Work Mode ...........................................................................................................................................19
3 Installation....................................................................................................................................23
3.1 Announcements..............................................................................................................................................23
3.2 Installation Preparation ..................................................................................................................................23
3.2.1 Tools......................................................................................................................................................23
3.2.2 Install Environment...............................................................................................................................24
3.2.3 Install Space..........................................................................................................................................24
3.2.4 Select Breaker & Wires.........................................................................................................................24

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3.2.5 Select Input Breaker..............................................................................................................................25
3.2.6 Select Wires ..........................................................................................................................................26
3.3 Transport and Unpacking ...............................................................................................................................27
3.3.1 Transport...............................................................................................................................................27
3.3.2 Unpacking.............................................................................................................................................28
3.4 Mechanical Installation ..................................................................................................................................29
3.5 Electrical Connection.....................................................................................................................................32
3.5.1 UPS Wiring Operation ..........................................................................................................................32
3.5.2 Wiring Between UPS and External Battery ..........................................................................................37
3.5.3 Wiring of Parallel System .....................................................................................................................41
4 Touch Screen Operation ............................................................................................................44
4.1 Menu Hierarchy .............................................................................................................................................44
4.2 Main Page ......................................................................................................................................................46
4.2.1 Icon Meaning ........................................................................................................................................46
4.2.2 Working Status......................................................................................................................................47
4.2.3 Bypass Information Page ......................................................................................................................49
4.2.4 Mains Informaiton Page........................................................................................................................50
4.2.5 Battery Information Page......................................................................................................................50
4.2.6 Output Information Page.......................................................................................................................51
4.3 Login Page .....................................................................................................................................................52
4.4 Information Management Page ......................................................................................................................52
4.4.1 Run Information Page ...........................................................................................................................53
4.4.2 History Record Page .............................................................................................................................55
4.4.3 User Log Page.......................................................................................................................................55
4.4.4 Device Infomation Page........................................................................................................................56
4.5 Setting Management Page..............................................................................................................................57
4.5.1 System Manage Page ............................................................................................................................57
4.5.2 Battery Management Page ....................................................................................................................60
4.5.3 Battery Test Page ..................................................................................................................................63
4.5.4 Dry Contact Page ..................................................................................................................................64

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User Manual
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4.5.5 HMI Setting Page..................................................................................................................................66
4.5.6 Password Setting Page ..........................................................................................................................67
4.5.7 Device Configuration Page...................................................................................................................67
4.5.8 Dedust Setting Page..............................................................................................................................70
4.5.9 Record Manage Page ............................................................................................................................71
4.6 Current Fault Page..........................................................................................................................................72
4.7 Buzzer Control ...............................................................................................................................................73
4.8 ON\OFF Operation.........................................................................................................................................74
5 LCD Screen Operation ...............................................................................................................76
5.1 Menu Hierarchy .............................................................................................................................................76
5.2 Main Page ......................................................................................................................................................77
5.3 System Working Status Display .....................................................................................................................77
5.4 Monitoring Page.............................................................................................................................................79
5.5 Setting Management.......................................................................................................................................79
5.5.1 Parameter Setting..................................................................................................................................80
5.5.2 Function Setting....................................................................................................................................81
5.5.3 Log Management ..................................................................................................................................83
5.5.4 Screen Setting .......................................................................................................................................83
5.5.5 Permission Setting ................................................................................................................................84
6 Use and Operation ......................................................................................................................86
6.1 Check Before Startup .....................................................................................................................................86
6.2 Startup Operation ...........................................................................................................................................86
6.3 Shutdown Operation.......................................................................................................................................87
6.4 Parallel System Operation..............................................................................................................................87
6.4.1 Start Parallel System.............................................................................................................................87
6.4.2 Shut Down Parallel System...................................................................................................................88
6.4.3 Exit Parallel System..............................................................................................................................88
6.4.4 Redundance Function of Parallel System..............................................................................................89
6.5 Periodic Preventative Maintenance................................................................................................................89
6.6 Battery Maintenance ......................................................................................................................................89

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User Manual
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6.7 Troubleshooting..............................................................................................................................................90
6.7.1 Common Fault ......................................................................................................................................90
7 Package, Transportation and Storage......................................................................................95
7.1 Package ..........................................................................................................................................................95
7.2 Transportation ................................................................................................................................................95
7.3 Storage ...........................................................................................................................................................95
A Technical Specifications ...........................................................................................................96
B Acronyms and Abbreviations ..................................................................................................99

MY-A Series (10kVA-20kVA) UPS
User Manual
1 Safety Description
1
1 Safety Description
This chapter introduces the safety announcements. Prior to performing any work on the UPS, please
read the user manual carefully to avoid human injury and device damage by irregular operations.
1.1 Safety Announcements
This section introduces the safety announcements that must be complied with and pay special
attention while installing, using, maintenance and other relative operations.
Before operating, please read the announcements and operation instructions in this section carefully
to avoid accident.
The DANGER, WARNING, CAUTION, etc. in the manual are not all the safety announcements that
you must abide by, they are just the supplements for the safety announcements during operating.
Our company does not undertake the responsibility caused by violating common safety operation
requirements or the safety standard of design, manufacture and use.
1.1.1 Safety Instructions
There exists high temperature and high voltage inside the UPS. During using, please strictly comply
with all warnings and operation instruments on the UPS and in the user manual.

1 Safety Description
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User Manual
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The UPS is class C3 device. If it is used in residential purpose, it may cause wireless interference.
User should take actions to avoid the interference.
No liquid or other objects are allowed to enter the UPS.
UPS must be well grounded.
In case of fire, please use dry power fire extinguisher. If using liquid fire extinguisher, it may
cause electric shock.
1.1.2 Use Announcements for Battery
The following instructions are for models with built-in batteries only.
Please use specified battery. Non-specified battery will damage the UPS.
Only authorized professional can replace battery. Do not wear conductive objects, such as
watches, bracelets and rings during operating. Wear rubber shoes and gloves and use tools with
insulated handle.
Don't put tools or other conductive objects on the battery.
It is prohibited to short the positive pole and negative pole of the battery or connect them
reversely, which is to avoid fire or electric shock.
Before connecting or disconnecting the battery terminals, disconnect charger first.
The battery must be with the same type, model and manufacturer.
Battery should be kept away from fire source or other electrical equipment that may easily cause
spark to avoid human injury.
Don't open or destroy the battery. The electrolyte in the battery includes some dangerous objects,
such as strong acid, which will be harmful to skin and eyes. If it is careless to touch the
electrolyte, clean it by a lot of water immediately and then check it in the hospital.
The waste battery should be disposed according to the local regulations.

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1 Safety Description
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1.1.3 Anti-Static Protection
The static generated by human bodies may damage the electrostatic-sensitive components on PCB.
Before touching the sensitive component, please wear anti-static rings and well connect the other end
of the anti-static rings to ground.
1.2 Operation and Maintenance Requirements
Only authorized professionals are allowed to open the UPS chassis, or it may cause electric shock
and the caused UPS fault is out of the guarantee range.
If UPS needs to be moved, rewired or maintained, disconnect all electrical connection, such as
AC power, battery power, etc. to isolate power input. Do not do any work on the UPS until it is
powered off completely (≥10min). Otherwise, the output may exist electricity, which may cause
electric shock.
When dismantling fan, do not put fingers or tools into the rotating fan to avoid device damage or
human injury.
1.3 Environment Requirements
Do not put the UPS in the environment where has inflammable, explosive gas or smog, do not do any
operation in this environment.
Do not use the UPS in the place where has direct sunshine, rain or wet.
The normal work temperature of UPS is -5℃~+40℃, relative humidity: 0%-95%RH, with no
condensation (recommended work temperature is 20℃~25℃, humidity is about 50%).

1 Safety Description
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User Manual
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Put the UPS in the flat floor without vibration and the vertical gradient is less than 5°. Keep good
ventilation around the UPS. The clearance between the rear or the side of UPS and adjacent
devices or wall should be at least 300mm~500mm. Poor ventilation will rise temperature inside
UPS, which will reduce the service life of inner components and even affect the life span of the
UPS.
The UPS must be used below 2000m. If the altitude exceeds 2000m, it needs to decrease the
rated power according to IEC62040-3: 2011 to use.

MY-A Series (10kVA-20kVA) UPS
User Manual
2 Overview
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2 Overview
This chapter mainly introduces the UPS's model meaning, features, structure, work principle, etc.
2.1 Product Intro
MY-A series UPS is whole high frequency, pure online, double-conversion, smart product. The
system is perfect power security for file server, enterprise server, center server, micro-computer,
concentrator, telecom system, data center and others that require high quality power protection. They
are widely used in many key business areas, such as post, finance, network, stock, petroleum,
refining, industrial power, electric power, automobile, etc.
2.1.1 Model Meaning
MY □□-A □
MY series online UPS
Rated power
When it is 10, that means the output power of the UPS is 10kVA;
When it is 15, that means the output power of the UPS is 15kVA;
And so on.
None: Without internalbattery and transformer;
S: With internalbattery;
T: With internaltransformer
A series
Work voltage is 110V/115V/120V/127V, default is 120V.
Figure2-1 Model meaning
1. UPS is three-phase input three-phase output mode (33 mode).
2. UPS standard parallel function and can be change single/parallel working mode through the
screen setting.

2 Overview
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2.1.2 Features
Completely digitalized smart control
The UPS can monitor the grid frequency (50Hz/60Hz) and self-adapt the frequency. The output
voltage can be set to 110V/115V/120V/127V, which makes the use more flexible.
Energy conservation and high efficiency
Adopts three-level inverter technology and PFC control technology, the output voltage wave is
perfect and the whole efficiency can be 94%, the input power factor is greater than 0.99, which
greatly improves the use ratio of electric energy and reduces the load of power grid.
Smart fan speed control
The fan speed is adjusted automatically in accordance with the load status, which prolong fan life and
reduce noise.
ECO energy conservation mode design
The UPS is designed with ECO energy conservation mode. When the grid is good, if the UPS
operating in this mode, the bypass prior to output, and the efficiency can be 99%.When the bypass
voltage or frequency out of normal range and cannot satisfy the user’s power supply requirement, it
will switch to inverter output, which guarantee the reliability of power supply and also, save energy.
Low mains input voltage
Adopt the independent rapid detection technology. When output load is small, even the battery
voltage is 70V, which is the mains low limit, the battery still doesn't discharge. Therefore, in the
mains mode, all output power gets from the grid, which is to ensure the battery in 100% energy
storage status, and at the same time, reduce the battery discharge times and prolong the service life.

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User Manual
2 Overview
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2.1.3 Appearance
Figure2-2 Appearance
UPS has two types of operation panels, touch screen and LCD screen (optional). In this manual, we
take the touch screen model as an example to illustrate.
Operation panel
Touch screen
Figure2-3 Operation panel

2 Overview
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User Manual
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Table2-1 Illustration for touch screen operation panel
No.
Name
Illustration
Illustration for operation panel
○
1
Touch screen display
Shows the working status and system setting.
○
2
AC/DC indicator
On (green): rectifier works normally;
On (red): rectifier abnormal.
○
3
DC/AC indicator
On (green): inverter works normally;
On (red): inverter abnormal.
○
4
BYP. indicator
On (green): bypass output;
On (red): bypass abnormal.
○
5
BATT. LOW indicator
On (red): battery is low-voltage.
○
6
OVERLOAD indicator
On (red): output is overload or overload protection.
Buttons operation instructions
○
7
"ON" combination button
Press a couple "ON" buttons for 1s at the same time, the
system will power on.
○
8
"OFF" combination button
Press a couple "OFF" buttons for 1s at the same time, the
system will power off.
○
9
EPO emergency power off
button
Press the button, the system will power outage immediately.
LCD screen (optional)
Figure2-4 Operation panel

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Table2-2 Illustration for LCD operation panel
No.
Name
Illustration
Illustration for operation panel
○
1
LCD screen display
Shows the working status and system setting.
○
2
" " page down button
and power off LED
indicator
Short press " " button, the LCD will enter next setting page.
○
3
" " function button and
breathing light
Short press " " button to confirm the command of the current
LCD page.
Long press " " button for 3s, will entry the parameter and
function setting page.
When UPS is on, " " button will be in a cycle of light up to
fade out.
○
4
" " page up button and
power on LED indicator
Short press " " button, the LCD will enter previous page or
previous option.
Combination buttons operation instructions
○
5
Power on
Press the " " and " " button for 2s at the same time, the UPS
on and the corresponding indicate LED is on.
○
6
Power off
Press the " " and " " button for 2s at the same time, the UPS
off and the corresponding indicate LED is on.

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Rear panel
Figure2-5 Structure of 10kVArear panel
Figure2-6 Structure of 15kVA/20kVArear panel

MY-A Series (10kVA-20kVA) UPS
User Manual
2 Overview
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1. When the UPS connect to external battery, 10kVA models can be directly connected to external
battery through wiring terminal bar; 15kVA/20kVA models are connected to external battery port,
and corresponding extension battery wiring assembly shall be selected.
2. The battery start operation: press "BATT. Start" button and wait for the buzzer sounds 7s, and
then the system establishes auxiliary power and then start ON operation, the device will start up.
1. Battery start only works in this case: the UPS power on through battery power when there is no
mains power.
2. The gate controlled switch release automatically when dismantle the maintenance breaker cover
plate, closes automatically when reinstall the cover plate.
3. Operation method of maintenance bypass mode: firstly, dismantle the maintenance breaker
cover plate, the door control switch for maintenance bypass detection pops up automatically, the
UPS turns off the inverter and switches to bypass mode. Closes the maintenance bypass breaker
and then open the input breaker, bypass breaker and output breaker. Meanwhile, the
maintenance bypass power for load, and the UPS input and output power are all opened, so the
UPS can dismantle wire for maintenance.
4. Operation method of restoring maintenance bypass mode to inverter mode: close input breaker,
bypass breaker and output breaker in turn. When UPS working power is normal and touch
screen has display bypass output voltage, open maintenance bypass breaker, reinstall
maintenance bypass breaker cover plate. Finally, press ON combination button on UPS panel to
start UPS inverter power.
2.1.4 Communication
The supported communication method of this series UPS include RS485, parallel kit, communication
dry contact, RS485+relay card, protocol transfer card and SNMP card.
Table2-3 Communication method correspondence with hardware port
Communication way
Communication port
RS485
RS485
Dry contact
Dry contact 1: output dry contact (OUT.1~OUT.5);
Dry contact 2: input dry contact (EPO+IN. 1)

2 Overview
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User Manual
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Table2-4 Communication method correspondence with hardware port
Communication way
Sketch map
Communication port
Parallel kit
Parallel port
SNMP card
Slot 1
RS485+relay card (optional)
Slot 2 (choose any one)
Protocol transfer kit (optional)
SNMP card (optional)
RS485
The UPS adopt RS485 series port to communicate with PC. The corresponding pin relationship of
RS485 port between UPS and PC is as shown Table2-5.