Sungrow SG350HX-US User manual

SG350HX-USPV
Grid-Connected InverterUser
ManualSG350HX-US-UEN-Ver12-
202301
User Manual
PV Grid-Connected Inverter
SG350HX-US
SG350HX-US-UEN-Ver12-202301

I
All Rights Reserved
All Rights Reserved
No part of this document can be reproduced in any form or by any means without the prior
written permission of Sungrow Power Supply Co., Ltd (hereinafter "SUNGROW").
Trademarks
and other Sungrow trademarks used in this manual are owned by
SUNGROW.
All other trademarks or registered trademarks mentioned in this manual are owned by their
respective owners.
Software Licenses
• It is prohibited to use data contained in firmware or software developed by SUNGROW,
in part or in full, for commercial purposes by any means.
• It is prohibited to perform reverse engineering, cracking, or any other operations that
compromise the original program design of the software developed by SUNGROW.

II
About This Manual
The manual mainly contains the product information, as well as guidelines for installation,
operation, and maintenance. The manual does not include complete information about the
photovoltaic (PV) system. Readers can get additional information at www.sungrowpower.
com or on the webpage of the respective component manufacturer.
Validity
This manual is valid for the following model of low-power grid-connected PV string inverters:
• SG350HX-US
It will be referred to as "inverter" hereinafter unless otherwise specified.
Target Group
This manual is intended for professional technicians who are responsible for installation, op-
eration, and maintenance of inverters, and users who need to check inverter parameters.
The inverter must only be installed by professional technicians. The professional technician
is required to meet the following requirements:
• Know electronic, electrical wiring and mechanical expertise, and be familiar with electri-
cal and mechanical schematics.
• Have received professional training related to the installation and commissioning of elec-
trical equipment.
• Be able to quickly respond to hazards or emergencies that occur during installation and
commissioning.
• Be familiar with local standards and relevant safety regulations of electrical systems.
• Read this manual thoroughly and understand the safety instructions related to
operations.
How to Use This Manual
Please read this manual carefully before using the product and keep it properly at a place
for easy access.
All contents, pictures, marks, and symbols in this manual are owned by SUNGROW. No part
of this document may be reprinted by the non-internal staff of SUNGROW without written
authorization.
Contents of this manual may be periodically updated or revised, and the actual product pur-
chased shall prevail. Users can obtain the latest manual from support.sungrowpower.com
or sales channels.
Symbols
This manual contains important safety instructions, which are highlighted with the following
symbols, to ensure personal and property safety during usage, or to help optimize the prod-
uct performance in an efficient way.
Please carefully understand the meaning of these warning symbols to better use the manual.

III
Indicates high-risk potential hazards that, if not avoided, may lead to death or seri-
ous injury.
Indicates moderate-risk potential hazards that, if not avoided, may lead to death or
serious injury.
Indicates low-risk potential hazards that, if not avoided, may lead to minor or mod-
erate injury.
Indicates potential risks that, if not avoided, may lead to device malfunctions or fi-
nancial losses.
“NOTE” indicates additional information, emphasized contents or tips that may be
helpful, e.g., to help you solve problems or save time.

V
Contents
All Rights Reserved .....................................................................................................I
About This Manual......................................................................................................II
1 Safety Instructions ............................................................................................1
1.1 Unpacking and Inspection ...............................................................................2
1.2 Installation Safety ...........................................................................................2
1.3 Electrical Connection Safety............................................................................3
1.4 Operation Safety ............................................................................................4
1.5 Maintenance Safety........................................................................................5
1.6 Disposal Safety ..............................................................................................6
2 Product Description ..........................................................................................7
2.1 System Introduction........................................................................................7
2.2 Product Introduction........................................................................................8
2.3 Symbols on Product........................................................................................9
2.4 LED Indicator ...............................................................................................10
2.5 DC Switch.................................................................................................... 11
2.6 Circuit Diagram ............................................................................................ 11
2.7 Function Description .....................................................................................12
3 Unpacking and Storage .................................................................................13
3.1 Unpacking and Inspection .............................................................................13
3.2 Unpacking Steps ..........................................................................................13
3.3 Inverter Storage ...........................................................................................15
4 Mechanical Mounting .....................................................................................16
4.1 Safety During Mounting.................................................................................16
4.2 Location Requirements .................................................................................17
4.2.1 Environment Requirements..................................................................17
4.2.2 Carrier Requirements ..........................................................................18
4.2.3 Angle Requirements............................................................................18
4.2.4 Clearance Requirements .....................................................................19
4.3 Installation Tools...........................................................................................21
4.4 Moving Inverter ............................................................................................22
4.4.1 Manual Transport................................................................................23

VI
4.4.2 Hoisting Transport...............................................................................23
4.5 Installing Mounting-bracket............................................................................25
4.5.1 Bracket-Mounted Installation................................................................26
4.5.2 Wall-Mounted Installation.....................................................................28
4.5.3 Pole-Mounting ....................................................................................30
4.6 Installing the Inverter.....................................................................................33
5 Electrical Connection .....................................................................................34
5.1 Safety Instructions........................................................................................34
5.2 Terminal Description .....................................................................................36
5.3 Electrical Connection Overview .....................................................................37
5.4 Crimp OT/DT terminal...................................................................................39
5.5 External Protective Grounding Connection .....................................................40
5.5.1 External Protective Grounding Requirements ........................................ 40
5.5.2 Connection Procedure.........................................................................41
5.6 AC Cable Connection ...................................................................................41
5.6.1 AC Side Requirements ........................................................................41
5.6.2 Requirements for OT/DT Terminal ........................................................44
5.6.3 Connection Procedure.........................................................................44
5.7 DC Cable Connection ...................................................................................48
5.7.1 PV Input Configuration ........................................................................49
5.7.2 Assembling PV Connectors .................................................................52
5.7.3 Installing PV Connector .......................................................................53
5.8 RS485 Connection(COM1)............................................................................55
5.8.1 Interface Description ...........................................................................55
5.8.2 RS485 Communication System............................................................55
5.8.3 Connection Procedure.........................................................................56
5.9 PLC Communication Connection ...................................................................59
6 Commissioning ...............................................................................................61
6.1 Inspection Before Commissioning..................................................................61
6.2 Commissioning Procedure ............................................................................61
7 iSolarCloud App ..............................................................................................63
7.1 Brief Introduction ..........................................................................................63
7.2 Installing App ...............................................................................................63
7.3 Login ...........................................................................................................64
7.3.1 Requirements .....................................................................................64
7.3.2 Login Procedure .................................................................................64

VII
7.4 Function Overview........................................................................................67
7.5 Home ..........................................................................................................67
7.6 Run Information............................................................................................69
7.7 Records.......................................................................................................71
7.8 More............................................................................................................73
7.8.1 System Parameters.............................................................................73
7.8.2 Operation Parameters .........................................................................74
7.8.3 Power Regulation Parameters..............................................................75
7.8.4 Communication Parameters.................................................................80
7.8.5 Firmware Update ................................................................................81
7.8.6 Password Changing ............................................................................82
8 Troubleshooting and Maintenance ..............................................................83
8.1 Troubleshooting ...........................................................................................83
8.2 Maintenance ................................................................................................91
8.2.1 Maintenance Notices...........................................................................91
8.2.2 Disconnecting Inverter.........................................................................92
8.2.3 Routine Maintenance ..........................................................................93
8.2.4 Cleaning Air Inlet and Outlet.................................................................93
8.2.5 Fan Maintenance ................................................................................94
8.2.6 Heat Sink Cleaning .............................................................................96
8.3 Inverter Disposal ..........................................................................................97
8.3.1 Dismantling the Inverter.......................................................................97
8.3.2 Disposal of Inverter .............................................................................98
9 Appendix ..........................................................................................................99
9.1 Technical Data .............................................................................................99
9.2 Wring Distance of DI Dry Contact................................................................. 100
9.3 Quality Assurance ......................................................................................102
9.4 Contact Information ....................................................................................102

1
1Safety Instructions
When installing, commissioning, operating, and maintaining the product, strictly observe the
labels on the product and the safety requirements in the manual. Incorrect operation or work
may cause:
• Injury or death to the operator or a third party.
• Damage to the product and other properties.
• Do not operate the product and cables (including but not limited to moving the
product, installing the product, operating the product and cables, powering up
the product, maintaining the product, and working at heights) in harsh weather
conditions such as lightning, rain, snow, and level 6 or stronger wind.
• In case of fire, evacuate from the building or product area and call the fire alarm.
Re-entry into the burning area is strictly prohibited under any circumstances.
• Tighten the screws with the specified torque using tools when fastening the
product and terminals. Otherwise, the product may be damaged. And the dam-
age caused is not covered by the warranty.
• Learn how to use tools correctly before using them to avoid hurting people or
damaging the device.
• Maintain the device with sufficient knowledge of this manual and use proper
tools.
• The safety instructions in this manual are only supplements and cannot cover
all the precautions that should be followed. Perform operations considering ac-
tual onsite conditions.
• SUNGROW shall not be held liable for any damage caused by violation of gen-
eral safety operation requirements, general safety standards, or any safety in-
struction in this manual.
• When installing, operating, and maintaining the product, comply with local laws
and regulations. The safety precautions in this manual are only supplements
to local laws and regulations.

2
1.1 Unpacking and Inspection
• Check all safety signs, warning labels and nameplates on devices.
• The safety signs, warning labels and nameplates must be clearly visible and
cannot be removed or covered before the device is decommissioned.
After receiving the product, check whether the appearance and structural parts of
the device are damaged, and check whether the packing list is consistent with the
actual ordered product. If there are problems with the above inspection items, do
not install the device and contact your distributor first. If the problem persists, con-
tact SUNGROW in time.
1.2 Installation Safety
• Make sure there is no electrical connection before installation.
• Before drilling, avoid the water and electricity wiring in the wall.
Improper installation may cause personal injury!
• If the product supports hoisting transport and is hoisted by hoisting tools, no
one is allowed to stay under the product.
• When moving the product, be aware of the product weight and keep the balance
to prevent it from tilting or falling.
Before operating the product, must check and ensure that tools to be used have
been maintained regularly.
1 Safety Instructions User Manual

3
1.3 Electrical Connection Safety
• Before electrical connections, please make sure that the inverter is not dam-
aged, otherwise it may cause danger!
• Before electrical connections, please make sure that the inverter switch and all
switches connected to the inverter are set to "OFF", otherwise electric shock
may occur!
The PV string will generate lethal high voltage when exposed to sunlight.
• Operators must wear proper personal protective equipment during electrical
connections.
• Must ensure that cables are voltage-free with a measuring instrument before
touching DC cables.
• Respect all safety instructions listed in relevant documents about PV strings.
• The inverter must not be connected to a PV string that requires positive or neg-
ative grounding.
Danger to life due to a high voltage inside the inverter!
• Be sure to use special insulation tools during cable connections.
• Note and observe the warning labels on the product, and perform operations
strictly following the safety instructions.
• Respect all safety instructions listed in this manual and other pertinent
documents.
Damage to the product caused by incorrect wiring is not covered by the warranty.
• Electrical connection must be performed by professionals.
• All cables used in the PV generation system must be firmly attached, properly
insulated, and adequately dimensioned.
User Manual 1 Safety Instructions

4
• Check the positive and negative polarity of the PV strings, and connect the PV
connectors to corresponding terminals only after ensuring polarity correctness.
• During the installation and operation of the inverter, please ensure that the posi-
tive or negative poles of PV strings do not short-circuit to the ground. Other-
wise, an AC or DC short-circuit may occur, resulting in equipment damage. The
damage caused by this is not covered by the warranty.
Comply with the safety instructions related to PV strings and the regulations re-
lated to the local grid.
1.4 Operation Safety
When routing cables, ensure a distance of at least 30 mm between the cables and
heat-generating components or areas to protect the insulation layer of cables from
aging and damage.
When the product is working:
• Do not touch the product enclosure.
• It is strictly forbidden to plug and unplug any connector on the inverter.
• Do not touch any wiring terminal of the inverter. Otherwise, electric shock may
occur.
• Do not disassemble any parts of the inverter. Otherwise, electric shock may
occur.
• It is strictly forbidden to touch any hot parts of the inverter (such as the heat
sink). Otherwise, it may cause burns.
• Do not connect or remove any PV string or any PV module in a string. Other-
wise, electric shock may occur.
1 Safety Instructions User Manual

5
1.5 Maintenance Safety
Risk of inverter damage or personal injury due to incorrect service!
• Before maintenance, disconnect the AC circuit breaker on the grid side and
then the DC switch. If a fault that may cause personal injury or device damage
is found before maintenance, disconnect the AC circuit breaker and wait until
the night before operating the DC switch. Otherwise, a fire inside the product or
an explosion may occur, causing personal injuries.
• After the inverter is powered off for 5 minutes, measure the voltage and current
with professional instrument. Only when there is no voltage nor current can op-
erators who wear protective equipment operate and maintain the inverter.
• Even if the inverter is shut down, it may still be hot and cause burns. Wear pro-
tective gloves before operating the inverter after it cools down.
Touching the power grid or the contact points and terminals on the inverter con-
nected to the power grid may lead to electric shock!
• The power grid side may generate voltage. Always use a standard voltmeter to
ensure that there is no voltage before touching.
To prevent misuse or accidents caused by unrelated personnel, post prominent
warning signs or demarcate safety warning areas around the product.
To avoid the risk of electric shock, do not perform any other maintenance opera-
tions beyond this manual. If necessary, contact SUNGROW for maintenance. Oth-
erwise, the losses caused is not covered by the warranty.
• If the paint on the inverter enclosure falls or rusts, repair it in time. Otherwise,
the inverter performance may be affected.
• Do not use cleaning agents to clean the inverter. Otherwise, the inverter may be
damaged, and the loss caused is not covered by the warranty.
• As the inverter contains no parts that can be maintained, never open the enclo-
sure of the inverter or replace any internal components without authorization.
Otherwise, the loss caused is not covered by the warranty.
User Manual 1 Safety Instructions

6
1.6 Disposal Safety
Please scrap the product in accordance with relevant local regulations and stand-
ards to avoid property losses or casualties.
1 Safety Instructions User Manual

7
2Product Description
2.1 System Introduction
The inverter is a transformerless 3-phase PV grid-connected inverter. As an integral compo-
nent in the PV power system, the inverter is designed to convert the direct current power
generated from the PV modules into grid-compatible AC current and to feed the AC current
into the utility grid.
Do not connect any local load between the inverter and the AC circuit breaker ex-
cept for the tracking axis.
• When designing the system, ensure that the operating ranges of all devices that
are connected to the inverter meet the requirements of the inverter.
• The inverter is only applicable to the scenarios described in the manual and
cannot be used in other situations.
The intended usage of the inverter is illustrated in the following figure.
figure 2-1 Inverter Application in PV Power System
Item Description Note
APV strings Monocrystalline silicon, polycrystalline silicon and thin-film
without grounding
B Inverter SG350HX-US
C Transformer Raises the output voltage of the inverter to a level that meets
the requirements of the grid
DUtility grid The grid form supported by the inverter is shown in the figure
below

8
2.2 Product Introduction
Model Description
The model description is as follows.
Appearance
The following figure shows the appearance of the inverter.
figure 2-2 Appearance
The image shown here is for reference only. The actual product received may differ.
No. Name Description
1 LED indicator To indicate the current working state of the inverter.
2AC junction box To connect AC cable and tracking system power cable in
this area.
3
External protec-
tive grounding
terminals
2, use at least one of them to ground the inverter.
2 Product Description User Manual

9
No. Name Description
4 Bottom handles 2, used to move the inverter.
5Mounting lugs 4, used to hang the inverter onto the mounting-bracket.
6Wiring area DC switches, DC terminals, and communication terminals.
For details, refer to "5.2 Terminal Description".
7 Labels To clearly identify the product, including nameplate, warning
symbols and QR code.
Dimensions
The following figure shows the dimensions of the inverter.
figure 2-3 Product Dimensions(in mm)
Weight
Model Weight
SG350HX-US ≤ 122 kg
2.3 Symbols on Product
Symbol Explanation
Do not dispose of the inverter together with household waste.
Read the user manual before maintenance!
CSA mark of conformity.
CE mark of conformity.
EU/EEA Importer
Disconnect the inverter from all the external power sources be-
fore maintenance!
User Manual 2 Product Description

10
Symbol Explanation
Burn danger due to the hot surface that may exceed 60℃.
Danger to life due to high voltages!
Do not touch live parts for 5 minutes after disconnection from
the power sources.
Only qualified personnel can open and maintain the inverter.
External protective grounding terminal.
2.4 LED Indicator
The LED indicator on the front of the inverter indicates the working state of the inverter.
table 2-1 LED Indicator State Description
LED Color State Definition
Blue
On The device is connected to the grid and operating
normally.
Fast blink
(Period: 0.2s)
The Bluetooth connection is established, and there is
data communication.
No system fault occurs.
Slow blink
(Period: 2s) The device is in standby or startup state (not feeding
power into the grid).
Slow blink
once, fast
blink three
times
The inverter is performing PID recovery.
Red
On A fault occurs and the device cannot connect to the
grid.
Blink The Bluetooth connection is established, data commu-
nication in process, and a system fault occurs.
Gray
OFF Both the AC and DC sides are powered down.
2 Product Description User Manual