KStar KAC50DP User manual

KAC50DP Industrial and Commercial
Power Conversion System
User Manual
Shenzhen Kstar New Energy Co., Ltd.
V1.0

1
Contents
1About This Manual ............................................................................................................ 1
1.1 Introduction ...................................................................................................................1
1.2 Applicable Products .......................................................................................................1
1.3 Naming Rules of Product Models...................................................................................1
1.4 Manual Description........................................................................................................1
1.5 Description of Signs........................................................................................................2
2Safety Instructions............................................................................................................. 2
2.1 Personnel Requirements................................................................................................3
2.2 Safety Warning Operation .............................................................................................3
2.3 Protection of Symbols on Equipment Body ...................................................................3
2.4 Matters on Electricity Safety..........................................................................................3
2.5 Requirements of Environmental Space..........................................................................4
2.6 Specification of Live Test................................................................................................4
2.7 Parameters Setting.........................................................................................................5
2.8 Maintenance or Overhaul Specifications.......................................................................5
2.9 Product Scrapping..........................................................................................................5
2.10 Other Precautions ........................................................................................................6
3 Product Introductions............................................................................................................. 7
3.1Power Conversion System ..............................................................................................7
3.2 Product Appearance.......................................................................................................8
3.3Main Power Topology.....................................................................................................9
3.4 Product Features............................................................................................................9
3.5 Communication Scheme ................................................................................................9
4 PCS Modes and Functions .................................................................................................... 11
4.1Mode Introduction........................................................................................................11
4.2 PCS Functions...............................................................................................................12
4.3 Introduction to PCS States ...........................................................................................13
5Guide for Mechanical Installation ......................................................................................... 14
5.1Precautions before Installation.....................................................................................14
5.2 Installation Process ......................................................................................................14
5.3 Preparation for Installation..........................................................................................15
5.4 Machine Transportation ..............................................................................................16
5.5 Positioning and Fixing ..................................................................................................17

5.6 Air Duct Design and Installation...................................................................................19
6Electrical Installation Instructions ......................................................................................... 20
6.1 Cable Requirements.....................................................................................................20
6.2 Wiring Specifications....................................................................................................20
6.3 Fixing and Protection of Connecting Cables ................................................................21
6.4 DC Side Wiring..............................................................................................................23
6.5 AC Side Wiring..............................................................................................................24
6.6 Communication interface ............................................................................................25
6.7 System Grounding........................................................................................................26
6.8 Installation Complete...................................................................................................26
7Commissioning ................................................................................................................ 27
7.1 Check before Starting...................................................................................................27
7.2 Power on/off operation process..................................................................................28
7.3 Fault shutdown operation process ..............................................................................28
8 Maintenance and Troubleshooting...................................................................................... 28
8.1 Description...................................................................................................................30
8.2 Precautions ..................................................................................................................30
8.3 Troubleshooting...........................................................................................................32
Appendix 1: Technical Parameters.......................................................................................... 36
Appendix 2: Quality Assurance................................................................................................ 38

About This Manual
1
1About This Manual
1.1 Introduction
Dear user, thank you very much for using the power conversion system developed and
produced by Shenzhen Kstar New Energy Co., Ltd. We sincerely hope that this product can
meet your needs. We also look forward to your valuable opinions on the performance and
functions of this product. We will continue to improve.
1.2 Applicable Products
This manual is suitable for the industrial and commercial power conversion system of
Shenzhen Kstar New Energy Co., Ltd.: KAC50DP
※Unless otherwise specified, all references to “PCS” and “power conversion system” in this manual refer
to this series of products.
1.3 Naming Rules of Product Models
Field 1
Field 2
Field 3
Field 4
Field 5
Field 6
System
model
K
A
C
50
D
P
KAC50DP
KSTAR
AC
Converter
Power
Outdoor
PV
1.4 Manual Description
This Manual is a special instruction manual for the KAC50DP seriesprovided by Shenzhen
Kstar New Energy Co., Ltd. The Manual introduces product-related information,
installation instructions, operation, maintenance, and troubleshooting in detail. Before
installing and commissioning the equipment, please read and understand all the
instructions contained in this Manual, and be familiar with the relevant safety symbols.
Readers need to have certain knowledge in electrical theory, electrical wiring and
equipment. Please read this Manual carefully before installing this product, and ensure
that the relevant personnel can easily obtain and use it.
The content, pictures, logos and symbols used in this Manual are owned by Shenzhen
Kstar New Energy Co., Ltd. It is prohibited to publicly reproduce all or part of the content
without written authorization of Kstar.

About This Manual
2
1.5 Description of Signs
In order to ensure the personal and property safety of users when using this product, and
make better use of this product, relevant information is provided in the Manual and
highlighted with appropriate symbols.
Below list the symbols that may be used in this Manual. Please read it carefully.
Danger
Indicate a situation that has a high degree of potential hazard, which will result in death or
serious injury if not avoided.
Warning
Indicate that there is a moderate potential hazard, which may cause death or serious injury
if not avoided.
Caution
Indicate that there is a low-level potential hazard, which may cause moderate or light injury
to personnel if not avoided.
Attention
Indicate that there is a potential risk, which may cause the equipment to fail to operate
normally or report a failure if not avoided.
“Description” emphasizes and supplements the content and may also provide techniques for optimizing
the use of the product.
Please always pay attention to the hazard warning symbols on the equipment. The symbols
include:
Symbol
Description
This symbol indicates that the equipment contains high voltage inside and touching it may
cause electric shock.
This symbol indicates that the temperature here is higher than the acceptable range for
the human body. Do not touch it in order to avoid personal injury.
This symbol indicates the protective ground (PE) terminal, which needs to be firmly
grounded to ensure the safety of the operator.

Safety Instructions
3
2Safety Instructions
2.1 Personnel Requirements
Only professional electricians or qualified personnel are allowed to perform operations
on this product.
The operators should be fully familiar with the structure and working principle of the
whole power conversion system.
The operators should be fully familiar with this User Manual of KAC50DP Power
Conversion System.
The operators should be fully familiar with the relevant standards of the country/region
where the project is located.
Warning
It is strictly forbidden to perform maintenance or overhaul operations when the
equipment is live!
When maintaining or overhauling the equipment, at least two operators must be on
site. The maintenance or overhaul operations can be performed only when the
equipment has been safely disconnected and the power conversion system has
discharged after 10 minutes.
2.2 Safety Warning Operation
During the installation, daily maintenance and overhaul of the power conversion system,
abide by the following in order to prevent unrelated personnel from approaching and causing
misoperation or accidents:
Set up conspicuous signs at the front and rear switches of the power conversion system
to prevent accidental switching.
Set up warning signs or safety warning belts near the operation area.
After maintenance or overhaul, be sure to lock the upper cover.
2.3 Protection of Symbols on Equipment Body
The warning symbols on the power conversion system contain important information
for safe operation of the power conversion system. Man-made tearing or damage is
strictly prohibited!
A nameplate is installed inside the front door of the power conversion system. The
nameplate contains important parameters of the product. Man-made tearing or damage
is strictly prohibited!
If any symbol is damaged or blurred, please contact Shenzhen Kstar New Energy Co., Ltd.
Attention
Please ensure that the symbols on equipment body are clear and readable at all times.
Once any symbol is damaged or blurred, it must be replaced immediately.

Safety Instructions
4
2.4 Matters on Electricity Safety
2.4.1 Electrical safety
Danger
Please ensure that the equipment is well grounded before use!
Danger
There is a lethal high voltage inside the product!
Do not touch the terminals or conductors connected to the grid circuit.
Pay attention to all instructions or safety documents about connecting to the power
grid, and follow the warning symbols on the product.
Observe the safety precautions listed in this Manual and other related documents of
this equipment.
Danger
Damaged equipment or system failure may cause electric shock!
Before operation, visually inspect the equipment for damage or other hazards.
Check whether other external equipment or circuit connections are safe.
Confirm that the equipment is in safe state before operation.
2.4.2 Electrostatic safety
Attention
Electrostatic sensitive components on the circuit board or elsewhere may be damaged due
to improper operation or contact by the operator.
Operators are required to avoid unnecessary contact with the circuit board.
Operators are required to comply with electrostatic protection regulations, such as
wearing ESD wristband.
2.5 Requirements of Environmental Space
2.5.1 Escape passage requirements
To ensure that the operator can quickly evacuate the scene in the event of an accident, please
observe the following:
Do not place flammable or explosive materials around the power conversion system.
It is strictly forbidden to stack debris in the escape passage or occupy the escape passage
in any form.
2.5.2 Moisture protection
Do not open the cover in high humidity or rainy days!

Safety Instructions
User Manual of KAC50DP Power Conversion System
5
2.6 Specification of Live Test
2.6.1Live measurement
Danger
There is high voltage in the equipment. Accidental contact may cause fatal electric shock.
Therefore, during live measurement, be sure to:
Take proper protection (such as wearing insulating gloves, insulating shoes, etc.).
At least two operators must be on site to ensure personal safety.
2.6.2 Use of measuring equipment
In order to ensure that the electrical parameters meet the requirements, it is necessary to
use related electrical measurement equipment when performing electrical connection and
trial operation of the power conversion system.
Warning
Select high-quality measuring equipment that meets the requirements of the site,
such as range and applicable conditions.
Ensure that the connection and use of the measuring equipment are correct and
standardized to avoid arcing and other dangers.
2.7 Parameters Setting
The parameters are closely related to the operation of the power conversion system. The
operating conditions of the system and the power conversion system must be reliably
analyzed and evaluated before these parameters can be modified. The specific parameters
are set in the background (PC or EMS).
Warning
Inappropriate parameter settings may affect the normal function of the power
conversion system!
Only authorized professionals can set the parameters of the power conversion system.
2.8 Maintenance or Overhaul Specifications
Pay attention to the following points when performing maintenance or overhaul operations
on the equipment:
Ensure that the power conversion system will not be re-powered accidentally.
Use a multimeter to ensure that the internal discharge of the power conversion system
has been completed.
Ensure that the equipment is properly grounded.
Live parts must be insulated and covered with insulating materials.
The upper cover can be opened for maintenance or overhaul of the power conversion
system after at least 10 minutes when the power conversion system has been shut down
and the AC-DC power supply has been disconnected.
During the entire process of maintenance and overhaul, it is necessary to ensure that
the escape passage is completely unblocked.

Safety Instructions
6
2.9 Product Scrapping
When the power conversion system needs to be discarded, it mustn’t be treated as
conventional waste.
Please contact the local authorized professional recycling agency.
2.10 Other Precautions
The actual operation summary should be based on site needs, and the following protective
or emergency measures should be taken:
When performing equipment maintenance, overhaul and other operations, relevant
personnel should take appropriate protective measures as needed, such as wearing
noise-proof earplugs, insulating shoes and anti-scald gloves.
The installation location of the power conversion system is usually far away from the
urban area. Corresponding emergency rescue facilities should be prepared for
implementation when needed.
Take all necessary auxiliary measures to ensure the safety of personnel and equipment.
Attention
All operations on the power conversion system must comply with the relevant standards of
the country/region where it is located.
All descriptions in this Manual are for the power conversion system with standard configuration. If you
have special needs, please explain to the staff of Shenzhen Kstar New Energy Co., Ltd. when ordering.
Please refer to the actual product you received for details.
This Manual can’t cover all possible situations in the process of operation, maintenance, and inspection.
If you have any question, please contact Shenzhen Kstar New Energy Co., Ltd. in time.

Product Introductions
7
3 Product Introductions
3.1Power Conversion System
On the power generation side, Power Conversion System (PCS) can effectively
connect renewable energy power generation such as solar power and wind power
to the power grid; on the transmission side, it can respond to the power grid and
achieve peak and frequency modulation, and peak load shifting to coordinate with
grid dispatch and stabilize the frequency of the power grid; when used on the power
distribution side, it can achieve peak load shifting to alleviate the power shortage
during the peak period of power consumption and smoothing the waste caused by
excess electric energy when the power consumption is low; on the power
consumption side, it can be used as a large uninterruptible power supply. It can
control the charging and discharging process of the battery, carry out AC/DC
conversion, and directly supply power to the AC load without power grid. PCS is
composed of DC/AC bidirectional converter, DC/DC bidirectional converter, MPPT
converter, control unit, etc. The PCS controller receives the background control
command through communication, controls the converter to charge or discharge
the battery according to the symbol and size of the power command, so as to realize
the adjustment of the active power and reactive power of the grid. PCS controller
communicates with BMS through CAN interface to obtain the status information of
the battery pack, which can realize protective charging and discharging of battery
and ensure the safety of battery operation.

Guide for Mechanical Installation
8
3.2 Product Appearance
The appearance of the power conversion system and the introduction of external
components are shown in the following figures:
Figure 3-1 Front view of KAC50DP
Figure 3-2 Bottom view of KAC50DP

Product Introductions
User Manual of KAC50DP Power Conversion System
9
3.3Main Power Topology
The PCS adopts two-phase staggered BOOST-BACK+T-type three-level topology to realize
four-quadrant operation; the filter circuit adopts an LCL filter circuit.
The principle of the main circuit inside the power conversion system is shown in the figures
below:
Figure 3-3 KAC50DP main circuit topology
3.4 Product Features
KAC50DP power conversion system adopts advanced digital control technology to optimize
control performance and improve system reliability. It is suitable for different battery
charging and discharging needs and the main performance features are as follows:
Accept power grid dispatch, communication method includes CAN, RS485, etc.
Multiple working modes such as on-grid mode, off-grid mode, and hybrid mode.
Independent and controlled frequency and voltage regulation.
With off-grid independent inverter function, a micro-grid system is established by the
power conversion system to ensure the power supply of important loads.
Off-grid with strong three-phase unbalanced load capacity.
High frequency design scheme, high power density.
Use AC/DC dual auxiliary power supply mode to improve reliability.
Independent air duct, excellent heat dissipation.
3.5 Communication Scheme
3.5.1 Background communication scheme
The PCS communicates with the EMS through RS485, and the EMS communicates with the
PC through Ethernet, and it is monitored by self-designed ESS monitoring software.

Guide for Mechanical Installation
10
3.5.2 EMS communication scheme
Through the RS485 communication line, the PCS can communicate with the EMS, and it can
be monitored in real time by self-designed ESS monitoring software.
3.5.3 BMS communication scheme
Through the CAN communication line, the PCS can communicate with the BMS to realize
data transmission.
Figure 3-4 PC monitoring via Ethernet
PC
Ethernet
EMS
Figure 3-6 BMS transmits data through CAN
PCS
RS485
EMS
Figure 3-5 EMS monitoring via RS485
CAN
PCS
BMS

Product Introductions
User Manual of KAC50DP Power Conversion System
11
4 PCS Modes and Functions
4.1Mode Introduction
4.1.1 On-grid mode and off-grid mode
Figure 4-1 System block diagram
On-grid mode: connected to the public grid, following the grid voltage amplitude/phase and
frequency, with island protection.
Off-grid mode: in the island state, the PCS operates in voltage source mode and outputs a given
voltage and frequency.
On-grid mode, off-grid mode: Mainly according to the on-site power grid situation, manually set
the PCS working mode.

Guide for Mechanical Installation
12
4.2 PCS Functions
4.2.1 Basic functions
Self-use:
The electricity generated by photovoltaic is stored or directly used by the load.
Off-peak power consumption:
During the working day, the load is mainly powered by photovoltaic and battery to
avoid snatching power at the peak of the power grid; at weekends, the power grid
supplies power and stores energy for the load.
Peak cutting and valley filling:
Through photovoltaic and ESS, the power demand for the grid is reduced during the
peak period of power consumption, and increased during the low period.
Charge and discharge control of energy storage battery
All KAC50DP models can be charged and discharged in on-grid mode. The depth of
charging and charging can be set by the user.
4.2.3 Cooling system start
The cooling system will automatically start when the PCS reaches a certain power or the
temperature reaches a threshold, and the speed will be adjusted steplessly.

Product Introductions
User Manual of KAC50DP Power Conversion System
13
4.3 Introduction to PCS States
The PCS has 5 states in total, as shown in Table 4-1 below:
Table 4-1 State and Description
State
Description
Self-test
When the DC side switch is turned on, the DC side of the
converter will perform a self-test to detect whether the DC
side voltage is normal.
Standby
After the self-test is completed, the DC side enters the
soft-start state, and when the soft-start ends, the DC
contactor closes, and the converter is in standby mode.
On-grid
After the system is in standby mode, if the power grid side
is normal at this time, the user can use EMS or PC to set
the converter operation mode to on-grid mode. When the
converter receives the boot command of the EMS or PC,
the relay on the AC side is closed, and the system is in the
on-grid operation state.
Off-grid
After the system is in standby mode, the user can use EMS
or PC to set the converter operation mode to off-grid
mode. When the converter receives the boot command of
the EMS or PC, the relay on the AC side is closed, and the
system is in the off-grid operation state.
Fault
All relays of the PCS are disconnected and the system
stops working.
Warning
When the PCS fails, it is forbidden to turn it on again.
Please turn off the power and check and ensure that there is no problem before powering
on again, or else it will cause damage to the machine.

Guide for Mechanical Installation
14
Preparation before installation
Mechanical installation
Electrical Installation
Installation verification
Commissioning test
Start
End
5Guide for Mechanical Installation
5.1Precautions before Installation
The installation of this series of PCS requires at least two qualified personnel to operate
at the same time, and all electrical installation must comply with local electrical
installation standards. Pay attention to prevent falling and smashing.
When installing, do not touch any other parts inside the chassis except for the wiring
terminals.
Safety signs “Work in progress! Do not switch on!” must be set up at all upstream
switches.
5.2 Installation Process
The installation process of KAC50DP power conversion system is as follows:
Figure 5-1 Installation flowchart

Guide for Mechanical Installation
及功能
User Manual of KAC50DP Power Conversion System
15
5.3 Preparation for Installation
5.3.1 Packaging inspection
Check whether the equipment is damaged before installation. If any transportation damage
is found, please contact the transportation company or Shenzhen Kstar New Energy Co., Ltd.
and provide a photo of the damage.
5.3.2 Checking delivery list
According to the packing list in the box, check whether all the delivered accessories are
complete and intact:
Table 5-1 Delivery List
Item
Quantity
Converter
1 PCS
User manual
1 PCS
External PV connection terminal (positive)
6 PCS
External PV connection terminal (negative)
6 PCS
AC OT terminal
5 PCS
Certificate
1 PCS
Warranty card
1 PCS
Mounting bracket (2 mounting bracket assemblies and 1
connecting rod)
1 PCS
RJ45 line end parallel plug
1 PCS
RS485/CAN plug
1 PCS
Bolt (M10)
4 PCS
Combination screw (M6)
2 PCS
Combination screw (M4)
2 PCS
Wrench (for removing PV connector)
1 PCS
L-type wrench (for cover removal)
1 PCS
External battery connection terminal (positive)
2 PCS
External battery connection terminal (negative)
2 PCS
5.3.3 Installation tools and parts
The tools and parts needed to install the power conversion system are as follows:
Table 5-2 List of Tools
Tool
Remark
Wire stripper
1 pcs
Crimping pliers
1 pcs
Screwdriver
1 set
Sleeve
1 set
Multimeter
1 set
Inner hexagon spanner
1 pcs
PV wrench
1 pcs
Screws, nuts, washers
Several

Guide for Mechanical Installation
16
5.3.4 Requirements of installation environment
Please confirm the following environment requirements before installing the power
conversion system:
Table 5-3 Environmental Requirements
Item
Requirement
Temperature
-20℃~50℃
Humidity
＜95% (no
condensation)
5.4 Machine Transportation
5.4.1 Transport Instructions
Transport the power conversion system with packaging as much as possible in order to
keep it in a better protective state.
When using a forklift or crane for transportation, pay attention to the weight of the
power conversion system, ensure that the transportation equipment has sufficient load-
bearing capacity and arrange supporting or lifting points reasonably.
Detailed product parameters and transportation requirements are marked on the outer
packaging. Please transport according to the signs on the packaging. The illustrations of
the PCS packaging signs are shown in Table 5-4 and 5-5:
Table 5-4 Description of Parameters on Package
Name
Description
MODEL
Model of power
conversion system
SIZE
Package size
NW
Net weight of PCS
GW
Gross weight of PCS with
outer packing box
Table 5-5 Description of Symbols on the Package
Symbol
Description
Keep the front side up. Do not place the PCS horizontally,
inclined or upside down.