KEHUA TECH KM-ACU User manual

Smart Communication Box KM-ACU
User Manual

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Copyright © Xiamen Kehua Digital Energy Tech Co., Ltd. 2022. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior
written consent of Xiamen Kehua Digital Energy Tech Co., Ltd.
Trademarks and Permissions
and other Kehua trademarks are the licensed trademarks of Xiamen Kehua Digital Energy
Tech Co., Ltd.
All other trademarks and trade names mentioned in this document are the property of their respective
holders.
Notice
The purchased products, services and features are stipulated by the contract made between Kehua and
the customer. All or part of the products, services and features described in this document may not be
within the purchase scope or the usage scope. Unless otherwise specification in the contract, all
statements, information, and recommendations in this document are provided “AS IS” without warranties,
guarantees or representations of any kind, either express or implied.
The information in this document is subject to change without notice. Every effort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations in this document do not constitute a warranty of any kind, express or implied.
XIAMEN KEHUA DIGITAL ENERGY TECH CO., LTD.
Address:
Room 208-38, Hengye Building, No. 100 Xiangxing Road, Torch High-tech
Zone (Xiang'an) Industrial Zone, Xiamen, China
Website:
www.kehua.com
E-mail:
[email protected]
Customer Service Telephone:
400-808-9986
Tel:
0592-5160516
Fax:
0592-5162166

Foreword
Smart Communication Box KM-ACU
User Manual
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Foreword
Summaries
Thank you for choosing the smart communication box!
This document gives a description of the smart communication box, including appearance, features,
working principles, installation, electrical connection, operation, maintenance and storage, etc.
Please save the manual after reading, in order to consult in the future.
The figures in this manual are just for reference, for details please see the actual product.
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 will, if not avoided, result in
serious injury or death.
Alerts you to a medium low risk hazard that could, if not avoided,
result in moderate or minor injury.
Alerts you to a low risk hazard that could, if not avoided, result in
minor injury.
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.

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Contents
1 Safety Description.........................................................................................................................1
1.1 Safety Announcements.....................................................................................................................................1
1.1.1 Use Announcements................................................................................................................................1
1.1.2 ESD Protection........................................................................................................................................3
1.1.3 Grounding Requirements........................................................................................................................3
1.1.4 Moistureproof Protection........................................................................................................................3
1.1.5 Warning Mark Setting.............................................................................................................................3
1.1.6 Electrical Connection..............................................................................................................................4
1.1.7 Measurement Under Operation...............................................................................................................4
1.2 Operator Requirements ....................................................................................................................................4
2 Overview.........................................................................................................................................6
2.1 Product Intro.....................................................................................................................................................6
2.1.1 Features...................................................................................................................................................7
2.2 Appearance and Structure.................................................................................................................................7
2.2.1 Appearance..............................................................................................................................................7
2.2.2 Bottom Layout........................................................................................................................................7
2.2.3 Size .........................................................................................................................................................9
2.3 Application Scheme .........................................................................................................................................9
2.3.1 PLC Communication(Optinal)..............................................................................................................10
2.3.2 PID Function(Optional) ........................................................................................................................10
2.3.3 IO Function(Optional)........................................................................................................................... 11
3 Installation....................................................................................................................................12
3.1 Installation Process.........................................................................................................................................12
3.2 Installation Tools............................................................................................................................................12

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3.3 Selection of Installation Site ..........................................................................................................................14
3.3.1 Installation Environment.......................................................................................................................14
3.3.2 Installation Clearance............................................................................................................................15
3.4 Transporting, Unpacking and Checking.........................................................................................................16
3.4.1 Transporting..........................................................................................................................................16
3.4.2 Unpacking and Checking......................................................................................................................16
3.5 Installation......................................................................................................................................................17
3.5.1 Wall-mounted Installation.....................................................................................................................17
3.5.2 Floor-mounted Installation....................................................................................................................25
3.6 Electrical Connection.....................................................................................................................................25
3.6.1 Safety Announcements..........................................................................................................................25
3.6.2 Wire Requirements................................................................................................................................26
3.6.3 Preparations for Electrical Connection .................................................................................................27
3.6.4 Electrical Connection Procedures.........................................................................................................28
3.7 Check the Installation.....................................................................................................................................36
4 Startup and Shutdown ...............................................................................................................37
4.1 Check Before Startup.....................................................................................................................................37
4.2 Start the Smart Communication Box..............................................................................................................37
4.3 Shut Down the Smart Communication Box...................................................................................................39
5 Maintenance.................................................................................................................................40
5.1 Maintenance...................................................................................................................................................40
6 Stop Running, Dismantle, Discard..........................................................................................42
6.1 Stop Running..................................................................................................................................................42
6.2 Dismantle the Smart Communication Box.....................................................................................................43
6.3 Discard the Smart Communication Box.........................................................................................................43
7 Package, Transportation, Storage.............................................................................................44
7.1 Package ..........................................................................................................................................................44
7.2 Transportation ................................................................................................................................................44
7.3 Storage ...........................................................................................................................................................44

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A Technical Specifications...........................................................................................................46
B Quality Assurance ......................................................................................................................48
C Acronyms and Abbreviations..................................................................................................50

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1 Safety Description
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1 Safety Description
This chapter mainly describes the safety announcements. Prior to performing any work on the
equipment, please read the user manual carefully, follow the operation and installation instructions
and observe all danger, warning and safety information.
1.1 Safety Announcements
This section mainly describes the safety announcements when operation and maintenance. For details,
please refer to safety description in relevant chapters.
Before operation, please read the announcements and operation instructions in this section carefully
to avoid accident.
The promptings in the user manual, such as "Danger", "Warning", "Caution", etc. don't include all
safety announcements. They are just only the supplement of safety announcements when operation.
Any equipment damage caused by violating the general safety operation requirements or safety
standards of design, production, and usage will be out of Kehua's guarantee range.
1.1.1 Use Announcements
Don't touch terminals or conductors that connected with grid to avoid lethal risk！

1 Safety Description
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There is no operational part inside the equipment. Please do not open the crust of the equipment by
yourself, or it may cause electric shock. The equipment damage caused by illegal operation is out of
the guarantee range.
After disconnect the input and output of the equipment, there still has residual energy in the storage
capacitor of equipment, which may cause electric shock. Do not perform the maintenance until all
power sources are switched off for 5 minutes.
The surface temperature of the equipment may reach to 75℃. During running, please don't touch the
surface to avoid scald.
No liquid or other objects are allowed to enter the equipment, or, it may cause equipment damage.
In case of fire, please use dry power fire extinguisher. If using liquid fire extinguisher, it may cause
electric shock.

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1.1.2 ESD Protection
To prevent human electrostatic damaging sensitive components (Such as circuit board), make sure
that you wear a anti-static wrist strap before touching sensitive components, and the other end is well
grounded.
1.1.3 Grounding Requirements
High leakage risk! The equipment must be grounded before wiring. The grounding terminal must be
connected to ground, or, it may cause electric shock when touching the equipment.
When installing, the equipment must be grounded first. When dismantling, the grounding wire
must be removed at last;
Don't damage the grounding conductor;
The equipment must be connected to protection grounding permanently;
Before operation, check the electrical connection to ensure the equipment is grounded reliably.
1.1.4 Moistureproof Protection
Moisture invasion may cause equipment damage!
Observe the following items to ensure the equipment works normally.
When the air humidity is more than 95%, don't open the door of the equipment;
In the wet or damp weather, don't open the door of the equipment to maintain or repair.
1.1.5 Warning Mark Setting
In order to avoid accident for unwanted person gets close to the equipment or makes improper
operation, observe the following requirements while installing, maintaining or repairing.

1 Safety Description
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Set warning marks where the switches are to avoid switching them on improperly.
Set warning signs or safety warning belt in the operation area, which is to avoid human injury or
equipment damage.
1.1.6 Electrical Connection
Electrical connection must be performed according to the description in the user manual and the
electrical circuit schematic.
Grid level, grid frequency, etc. must meet the technical requirements of equipment.
All electrical connection must meet the related country and district standard.
1.1.7 Measurement Under Operation
There exists high voltage in the equipment. If touching equipment accidently, it may cause electric
shock. So, when perform measurement under operation, it must take protection measure(Such as
wear insulated gloves, etc.)
The measuring equipment must meet the following requirements:
The range and operation requirements of measuring equipment meets the site requirements;
The connections for measuring equipment should be correct and standard to avoid arcing.
1.2 Operator Requirements
The operation and wiring for equipment should be performed by qualified person, which is to ensure
that the electrical connection meets the related standards.
The professional technicist must meet the following requirements:

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1 Safety Description
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Be trained strictly and understand all safety announcements and master correct operations.
Know well about the related standards of local country and district.

2 Overview
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2 Overview
This chapter mainly describes product appearance, structure, working principle and communication
method, etc.
2.1 Product Intro
The smart communication box includes RS485 port, PLC port, DI port, DO port, AI port, etc. to
collect data from PV array and then transmit it to the monitoring platform, which realizes the smart
communication and management of PV array. Besides, it has build-in lighting protection module to
keep equipment safe and reliable and supports the external meter and environment detector to
manage plant.
Data collector
RS485
RS485
RS485 chain1
RS485
……
RS485 chain3
SPID-S
RS485
RS485
……
Fiber switch User
SCADA
system
Meter
Environment
detector
RS485 chain6
RS485 chain5
RS485 chain4
PLC
PLC
PLC
PLC
CCO PLC
Fiber
KM-ACU
RS485
RS485 communication
AC wire
DC wire
PLC communication
Fiber
Isolation
transformer Grid
Figure2-1 PV smart communication system

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2.1.1 Features
Flexible and various networking methods, integrating with fiber switch, data logger, etc.
Include SPID module to prevent the PID effect of PV array and extend its service life.
Include PLC module to realize the smart communication control and it doesn't need to perform
wiring.
Support the double split winding transformer and configuring double PID modules and double
PLC modules are allowed.
Include lighting protection module to enhance the reliability.
Reach the IP 66 protection grade, and it can be used in the outdoor.
Support the flexible installation methods, including wall installation, bracket installation and
floor installation.
2.2 Appearance and Structure
2.2.1 Appearance
The appearance of the smart communication box is as shown in Figure2-2.
Figure2-2 Appearance
2.2.2 Bottom Layout
The bottom layout of the smart communication box is shown as Figure2-3.

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Figure2-3 Bottom layout
Table2-1 Mark description
NO.
Mark
Name
Remarks
○
1
Optical fiber ports
Fiber input wiring hole
Connect with fiber.
○
2
ETH
Ethernet wiring hole
Connect with the Ethernet
communication wire.
○
3
DO
DO wiring hole
Connect with DO signal wire
○
4
External grounding wiring hole
Connect with the external
grounding wire.
○
5
RS485
RS485 communication wiring
hole
Connect with the RS485
communication wire.
○
6
Input AC220V
AC 220V power wiring hole
Connect with the
single-phase AC 220V
power wire.
○
7
Input PID-PLC01
Input PID-PLC02
Three-phase AC power(Including
grounding function wire) wiring
hole
Connect with the PID/PLC
three-phase AC power.
○
8
DI
DI wiring hole
Connect with DI signal wire
○
9
AI
AI wiring hole
Connect with AI signal wire
○
10
PID/PLC AC Switch 1
PID/PLC AC Switch 2
Three-phase AC switch
Connect or disconnect with
three-phase AC input

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2.2.3 Size
Figure2-4 Size (Unit: mm)
2.3 Application Scheme
The smart communication box is used in outdoor. Data logger, RS485 signal SPD, PID module and
inductor, optical fiber terminal box, PLC module, SPD, etc. can be installed in the cabinet to realize
the communication and control of PV array. The networking application scheme of the smart
communication box is as shown in Figure2-5.
Environment
monitoring
instrument Inverter Box-type
transformer
Smart
communication box
Ethernet
switch
Ethernet
switch Ethernet
switch
Ethernet
switch
Ethernet
switch
Monitoring
platform
Figure2-5 Network application scheme

2 Overview
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2.3.1 PLC Communication(Optinal)
PLC module can use the power line as the transmission path. Place the smart communication box and
PV array in the same grid, and it will can realize the communication and management, which it
doesn't need to connect communication wire. The PLC communication is more convenient and
reliable, as shown in Figure2-6.
Inverter 1
Inverter 2 Smart
communication
box PC
Isolation
transformer Grid
Fiber
Inverter N
Figure2-6 PLC communication connection
If PLC communication is configured, the AC cables can only be multi-core cable, single-core
cable cannot be used.
The length of the AC cables between inverter and smart communication box should be within
300mm and cannot exceed 400mm.
2.3.2 PID Function(Optional)
If PID function is configured and enabled, the voltage of all PV arrays to ground is greater than zero,
that is to say, the voltage of all PV arrays to ground is positive voltage status.
Before enabling PID protection or repair function, please pay attention to the polarity
requirement for the voltage of different PV arrays to ground. If any doubt, please contact the
manufacturer of PV array or read the user manual of PV array.
When the type of PV array mismatches the voltage scheme of PID protection or repair function,
the PID function will not reach the expected effect even cause harmful influence for PV array.

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2.3.3 IO Function(Optional)
Detect and remotely control the each types of standard analogy values and switch values(e.g.
frequency, pulse or switch status signal) in the measurement and control area.

3 Installation
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3 Installation
This chapter mainly introduces the equipment's installation, including installation process,
installation preparation, handling, unpacking and checking, installation procedures, electrical
connection, check the installation, etc.
3.1 Installation Process
The installation process of the smart communication box is as shown in Figure3-1.
Start
Electrical connection
Check the
installation
End
Installation
preparation
Install smart
communication box
Install optional
components
Figure3-1 Installation process
3.2 Installation Tools
The recommended installation tools include but not limited to the following tools, if necessary, you
can also use other auxiliary tools according to the site conditions.