KEHUA TECH SPI-B Series User manual

String PV Grid-tied Inverter
SPI-B Series (100K-125K)
User Manual

All rights reserved ©Kehua Hengsheng Co., Ltd.
i
Copyright © KehuaHengshengCo.,Ltd.2020.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 Kehua Hengsheng Co., Ltd.
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and other Kehua trademarks are trademarks of Kehua Hengsheng 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.
KEHUA HENGSHENG CO.,LTD.
Address:
No.457,MalongRoad,TorchHigh-TechIndustrialZone,Xiamen,Fujian,China
Manufacturer:
ZHANGZHOU KEHUA TECHNOLOGYCO.,LTD.
Postal Code:
361000(XIAMEN), 363000(ZHANGZHOU)
Website:
www.kehua.com
E-mail:
[email protected]
Customer Service Telephone:
400-808-9986
Tel:
0592-5160516
Fax:
0592-5162166

Foreword
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
ii
All rights reserved ©Kehua Hengsheng Co., Ltd.
Foreword
Summaries
Thank you for choosing the SPI-B series (100K-125K) string PV grid-tied inverter (Hereinafter
referred to as inverter)!
This document gives a description of the inverter, 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.
Applicable Model
SPI100K-B
SPI125K-B
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, if not avoided, result in
serious injury or death.
Alerts you to a medium or low risk hazard that could, if not avoided,
result in moderate or minor injury.
Alerts you to a potentially hazardous situation that could, if not
avoided, result in equipment damage, data loss, performance
deterioration, or unanticipated results.

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
Foreword
All rights reserved ©Kehua Hengsheng Co., Ltd.
iii
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/XMHS 003
Change History
Changes between document issues are cumulative. The latest document issue contains all the changes
made in earlier issues.
Issue 001 (2020-08-07)
First issue.

Contents
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
iv
All rights reserved ©Kehua Hengsheng Co., Ltd.
Contents
1 Safety Description.........................................................................................................................1
1.1 Safety Announcements.....................................................................................................................................1
1.1.1 Use Announcements................................................................................................................................1
1.1.2 PV String Protection ...............................................................................................................................3
1.1.3 ESD Protection........................................................................................................................................3
1.1.4 Grounding Requirements........................................................................................................................3
1.1.5 Moistureproof Protection........................................................................................................................4
1.1.6 Warning Mark Setting.............................................................................................................................4
1.1.7 Electrical Connection..............................................................................................................................4
1.1.8 Measurement Under Operation...............................................................................................................5
1.2 Operator Requirements ....................................................................................................................................5
2 Overview.........................................................................................................................................6
2.1 Product Intro.....................................................................................................................................................6
2.1.1 Features...................................................................................................................................................7
2.1.2 Model Meaning.......................................................................................................................................7
2.2 Apperance and Structure ..................................................................................................................................8
2.2.1 Apperance ...............................................................................................................................................8
2.2.2 Operation Panel.......................................................................................................................................8
2.2.3 Bottom Layout ........................................................................................................................................9
2.2.4 Size........................................................................................................................................................ 11
2.3 Working Principle........................................................................................................................................... 11
2.4 Communication.............................................................................................................................................. 11
2.4.1 Ethernet Communication ...................................................................................................................... 11
2.4.2 RS485 Communication.........................................................................................................................12

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
Contents
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2.4.3 WIFI/GPRS Communication (Optional)...............................................................................................13
2.4.4 PLC Communication (Optional)...........................................................................................................14
2.4.5 PID Function (Optional) .......................................................................................................................16
3 Installation....................................................................................................................................18
3.1 Installation Process.........................................................................................................................................18
3.2 Installation Tools............................................................................................................................................18
3.3 Selection of Installation Site ..........................................................................................................................20
3.3.1 Installation Environment.......................................................................................................................20
3.3.2 Installation Clearance............................................................................................................................21
3.3.3 Requirements for Installation Carrier....................................................................................................23
3.3.4 Installation Method ...............................................................................................................................23
3.4 Transporting, Unpacking and Checking.........................................................................................................24
3.4.1 Transporting..........................................................................................................................................24
3.4.2 Unpacking and Checking......................................................................................................................26
3.5 Inverter Installation ........................................................................................................................................26
3.5.1 Bracket Installation ...............................................................................................................................26
3.5.2 Wall Mounting ......................................................................................................................................30
3.6 Electrical Connection.....................................................................................................................................34
3.6.1 Safety Announcements..........................................................................................................................34
3.6.2 Requirements for Wire..........................................................................................................................34
3.6.3 External Grounding Connection ...........................................................................................................35
3.6.4 AC Output Wiring.................................................................................................................................37
3.6.5 Internal Grounding Connection.............................................................................................................41
3.6.6 PV String Input Wiring .........................................................................................................................42
3.6.7 WIFI/GPRS Communication Connection (Optional) ...........................................................................47
3.6.8 COM. Communication Connection ......................................................................................................48
3.7 Check the Installation.....................................................................................................................................51
4 Startup and Shutdown ...............................................................................................................52
4.1 Check Before Startup .....................................................................................................................................52
4.2 Start Inverter...................................................................................................................................................52

Contents
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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4.3 Shut Down Inverter........................................................................................................................................53
5 Maintenance and Troubleshooting .........................................................................................54
5.1 Maintenance...................................................................................................................................................54
5.1.1 Maintenance Details and Period............................................................................................................54
5.1.2 Maintenance Guide...............................................................................................................................55
5.2 Troubleshooting..............................................................................................................................................58
6 Stop Running, Dismantle, Discard Inverter..........................................................................61
6.1 Stop Running..................................................................................................................................................61
6.2 Dismantle the Inverter....................................................................................................................................62
6.3 Discard the Inverter........................................................................................................................................62
7 Package, Transportation, Storage.............................................................................................63
7.1 Package ..........................................................................................................................................................63
7.2 Transportation ................................................................................................................................................63
7.3 Storage ...........................................................................................................................................................63
A Technical Specifications ...........................................................................................................64
B Quality Assurance ......................................................................................................................69
C Acronyms and Abbreviations..................................................................................................71

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
1 Safety Description
All rights reserved ©Kehua Hengsheng Co., Ltd.
1
1 Safety Description
This chapter mainly describes the safety announcements. Prior to performing any work on the device,
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 device 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
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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All rights reserved ©Kehua Hengsheng Co., Ltd.
There is no operational part inside the inverter. Please do not open the crust of the inverter by
yourself, or it may cause electric shock. The device damage caused by illegal operation is out of the
guarantee range.
After disconnect the input and output of the inverter, there still has residual energy in the storage
capacitor, which may cause electric shock. Do not perform the maintenance until all power sources
are switched off for 30 minutes.
Please do not put fingers or tools into the rotating fans to avoid human injury or device damage.
The surface temperature of the inverter 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 inverter, or, it may cause inverter damage.
In case of fire, please use dry power fire extinguisher. If using liquid fire extinguisher, it may cause
electric shock.

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
1 Safety Description
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1.1.2 PV String Protection
When install PV string in daytime, it necessary to cover the PV string by light-proof material, or the
PV string will generate high voltage under sunshine. If touching PV string accidently, it may cause
electric shock or human injury!
There exists dangerous voltage between the positive and negative of PV string!
When installing the device, make sure that the connection between inverter and PV string has been
disconnected completely. And set warning mark in the disconnected position to avoid reconnecting.
1.1.3 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.
1.1.4 Grounding Requirements
High leakage risk! The inverter must be grounded before wiring. The grounding terminal must be
connected to ground, or, there will be the risk of electric shock when touching the inverter.
When installing, the inverter must be grounded first. When dismantling, the grounding wire must
be removed at last;
Don't damage the grounding conductor;
The inverter must be connected to protection grounding permanently.
Before operation, check the electrical connection to ensure the inverter is grounded reliably.

1 Safety Description
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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All rights reserved ©Kehua Hengsheng Co., Ltd.
1.1.5 Moistureproof Protection
Moisture invasion may cause inverter damage!
Observe the following items to ensure the inverter works normally.
When the air humidity is more than 95%, don't open the door of the inverter;
In the wet or damp weather, don't open the door of the inverter to maintain or repair.
1.1.6 Warning Mark Setting
In order to avoid accident for unwanted person gets close to the inverter or makes improper operation,
observe the following requirements while installing, maintaining or repairing.
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
device damage.
1.1.7 Electrical Connection
Electrical connection must be performed according to the description in the user manual and the
electrical circuit schematic.
The configuration of PV string, grid level, grid frequency, etc. must meet the technical requirements
of inverter.
Grid-tied generation should be allowed by the local power supply department and the related
operation should be performed by professionals.
All electrical connection must meet the related country and district standard.

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
1 Safety Description
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1.1.8 Measurement Under Operation
There exists high voltage in the device. If touching device 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 device must meet the following requirements:
The range and operation requirements of measuring device meets the site requirements;
The connections for measuring device should be correct and standard to avoid arcing.
1.2 Operator Requirements
The operation and wiring for inverter 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:
Be trained strictly and understand all safety announcements and master correct operations.
Fully familiar with the structure and working principle of the whole PV grid-tied generation
system.
Know well about the related standards of local country and district.

2 Overview
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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All rights reserved ©Kehua Hengsheng Co., Ltd.
2 Overview
This chapter mainly describes product appearance, structure, working principle and communication
method, etc.
2.1 Product Intro
The inverter converts the DC energy from PV string into AC energy and then feedbacks to power grid,
which is suitable for the large power station grid-tied system. The PV grid-tied generation system
consists of PV string, PV grid-tied inverter, transformer and power distribution system, as shown
Figure2-1.
Figure2-1 PV grid-tied generation system
PV grid-tied power generation needs to obtain the permission of local power supply department and
performed by professionals.
The grid form supported by the inverter is shown in Figure2-2.

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
2 Overview
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Inverter
Transformer
IT
PE
L1
L2
L3
Figure2-2 Grid form
2.1.1 Features
Innovated three level design, with high transition efficiency.
Support PLC communication, night SVG function, which satisfies the requirement of grid
scheduling.
The reactive power is adjustable, the range of power factor is -0.8(lag)～+0.8(ahead).
Smart I-V scanning, fault wave capture, remote online update function.
Perfect protection functions: island protection, high/low voltage ride through, reverse DC
connection protection, AC short circuit protection, leakage current protection, surge protection,
etc.
2.1.2 Model Meaning
SPI □□□K-B
Product series mark
SPI series PV grid-tied inverter.
Rated output power mark
When it is 100, that means the rated power of the inverter is 100kVA;
When it is 125, that means the rated power of the inverter is 125kVA;
And so on.
Isolation type mark
“B”represents non-isolated power.
Figure2-3 Model meaning

String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
2 Overview
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NO.
Mark
Color
Meaning
Status illustration
OFF: All PV strings are disconnected.
○
2
Green
Grid indicator
ON: Grid-tied status.
Flicker: Inverter stay in decrease rated power
output status.
OFF: No grid-tied status.
○
3
Green
WIFI/GPRS
indicator
ON: WIFI/ GPRS has been connected.
OFF: WIFI/ GPRS has been disconnected.
○
4
Red
Fault indicator
ON: The inverter has alarm.
2.2.3 Bottom Layout
The inverter's bottom layout is shown as Figure2-6.
Figure2-6 Bottom layout
SPI100K-B has 18 groups PV string inputs. The connection identifiers MPPT10+ ~ MPPT12+,
MPPT10- ~ MPPT12- in Figure 2-6 are not installed with PV connectors.
The above figure takes SPI125K-B as an example to illustrate. If there is no special explanation, the
following we will take SPI125K-B as an example to explain.

2 Overview
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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Table2-2 Mark description
NO.
Mark
Name
Remarks
○
1
MPPT n +/MPPT n -
PV string input
terminal
Used to connect PV string input.
○
2
DC SWITCH
DC switch
It is the connection switch between
inverter and PV string. Each DC switch
controls the PV string input terminals of
marked area.
○
3
-
Breather valve
Used to balance the pressure difference
between inside and outside of the
inverter.
○
4
WIFI/GPRS
WIFI/GPRS interface
Used to WIFI/GPRS connection and
communication
○
5
AC OUTPUT
AC output wiring hole
Used to connect the wire of AC output.
○
6
COM.
Communication
wiring hole
Used to connect the communication wire
of RS485 or Ethernet.
○
7
○
8
Internal grounding
hole
For internal grounding.
○
9
External grounding
terminal
For the grounding of the inverter.
DC Switch
The DC switch (the position is shown as ○ 2 in Figure2-6) is the connection switch between the
inverter and the PV string, when necessary, it can safely disconnect the connection of the inverter and
the PV string. In order to ensure the safety of the operator, make sure that the DC switch is turned off
under the following conditions:
When installing and wiring, the DC switch must be placed to OFF position.
When checking and repairing, place the DC switch to OFF position and wait for 30 minutes. Use
a multimeter to measure the DC bus voltage inside the inverter, only when the voltage lower than
10V, you can perform repair work.

String PV Grid-tied Inverter SPI-B Series (100K-125K)
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2.2.4 Size
Figure2-7 Size (unit: mm)
2.3 Working Principle
The PV string input is connected to the inverter, and the maximum power point for the PV string is
tracked through the internal 12 groups of MPPT circuits to achieve the maximum power output of the
PV string, and then the conversion of DC power to three-phase AC power is realized through the
inverter circuit, as shown in Figure2-8.
Output
EMI filter
Relays
SPD
CHCT
HCT
HCT
( –)
( + )
( –)
( + )
( –)
( + )
MPPT1
C
( –)
( + )
PWM
+
–
GND
DC/DC1
DC/DC12
…
L1
L2
L3
PE
Input
EMI filter
…… ……
SPD
GND
GND
DC switch
L1 L2 L3
MPPT12
Figure2-8 Working principle diagram
2.4 Communication
The inverter has multiple communication methods, including Ethernet communication, RS485
communication, WIFI/GPRS communication (optional), and PLC communication (optional). Users
can easily obtain the current operation data of the inverter.
2.4.1 Ethernet Communication
Ethernet communication (the interface is shown in Figure2-9) is mainly used for local area network
monitoring, which can realize the background remote monitoring.

2 Overview
String PV Grid-tied Inverter SPI-B Series (100K-125K)
User Manual
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Figure2-9 Ethernet communication interface diagram
……
Inverter
Monitoring
platform
Inverter
Inverter
Router
Figure2-10 Ethernet monitoring (multiple inverters)
2.4.2 RS485 Communication
RS485 communication (the interface is shown in Figure2-11) is mainly used for local area network
monitoring, which can realize the background remote monitoring.