Sunways STT-80K User manual

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User Manual
Ningbo Sunways Technologies Co., Ltd.
Grid-connected PV Inverter
Three Phase Eight/Ten MPPT
STT-80K/100K/110K/125KTL

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CONTENTS
1. Preface ...................................................................................................................... 5
1.1 Overview ...................................................................................................... 5
1.2 Target Groups .............................................................................................. 5
2. Safety Instructions .............................................................................................. 5
2.1 Safety Notes ................................................................................................ 5
2.2 Statement .................................................................................................... 5
2.3 Important Safety Matters ........................................................................... 6
2.4 Symbols Explanation .................................................................................. 7
3. Product Introduction ......................................................................................... 9
3.1 Basic Features ............................................................................................. 9
3.2 Appearance Introduction ......................................................................... 10
3.3 Display Interface ....................................................................................... 12
3.4 Packing List ................................................................................................ 13
4. Product Installation .......................................................................................... 13
4.1 Selection of Installation Location ............................................................ 13
4.2 Mounting the Inverter ............................................................................... 15
4.3 Electrical Connection ............................................................................... 17
4.4 Monitoring Device Installation ................................................................. 22
4.5 RS485/DRED Connection .......................................................................... 23
5. Start and Stop .....................................................................................................27
5.1 Inverter start-up .......................................................................................27
5.2 Inverter shutdown .................................................................................... 27
6. General Operation ............................................................................................. 28
6.1 Display Operation .................................................................................... 28
6.2 Auto-Test ................................................................................................... 29
7. Troubleshooting................................................................................................. 30
7.1 Fault Messages ......................................................................................... 30
7.2 Maintenance ............................................................................................. 31
8. Technical Parameters ...................................................................................... 32

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Attention
The products, services or features you purchase are subject to the commercial contracts and
terms of Ningbo Sunways technologies Co., Ltd. All or part of the products, services or features
described in this document may not be within your purchasing or using scope. Unless otherwise
agreed in the contract, the Company shall not make any express or implied declaration or
guarantee of the contents of this document.
Due to product version upgrades or other reasons, the contents of this document will be
updated periodically. Unless otherwise agreed, this document serves only as a guide to use,
and all statements, information and recommendations in this document do not constitute any
express or implied guarantee.
Manufacturer: Ningbo Sunways technologies Co., Ltd.
Address: No. 1, Second Road, Green Industrial Zone, Chongshou Town,
Cixi City, ZheJiang Province, PEOPLE’S REPUBLIC OF CHINA
Website: www.sunways-tech.com
Service Mail: [e-mail]
Hotline: [phone]
1. Preface
1.1 Overview
This manual is an integral part of Sunways STT 80~125kW series three-phase inverters
(hereinafter referred to as the inverters). It mainly introduces the assembly, installation,
electrical connection, debugging, maintenance and troubleshooting of the products. Before
installing and using inverters, please read this manual carefully, understand the safety
information and be familiar with the functions and characteristics of inverters.
1.2 Target Groups
This manual is applicable to the electrical installers with professional quali󽗉cations and the
people who bought this inverter. If there are any problems in the installation process, please
call Sunways service telephone at [phone] or email Sunways at service@sunways-
tech.com for consultation.
2. Safety Instructions
2.1 Safety Notes
2.1.1 Before installation, you should read this manual carefully and follow the instructions in
this manual strictly.
2.1.2 Installation operators need to undergo professional training or obtain electrical related
professional quali󽗉cation certi󽗉cates.
2.1.3 When installing, do not touch any part of the inner part of the inverter except the
terminals.
2.1.4 All electrical installations must conform to local electrical safety standards.
2.1.5 If the inverter needs maintenance, please contact the local designated personnel for
system installation and maintenance.
2.1.6 To use this grid-connected inverter for power generation needs the permission of the
local power supply authority.
2.1.7 During the operation of the inverter, the surface temperature may be higher and there is
a risk of burns. Do not touch.
2.1.8 When installing photovoltaic panels in the daytime, the photovoltaic panels should be
covered with opaque materials to avoid the risks and danger of high voltage at the panel end
in sunlight.
2.2 Statement
Ningbo Sunways technologies Co., Ltd. has the right not to undertake quality assurance in any
of the following circumstances:
2.2.1 Damages caused by irregular transportation.

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2.2.2 Damages caused by incorrect storage, installation or use.
2.2.3 Damages caused by installation and use of equipment by non-professionals or untrained
personnel.
2.2.4 Damages caused by failure to comply with the instructions and safety warnings in the
products and documents.
2.2.5 Damages caused by running in an environment that doesn't meet the requirements
which stated in the documents.
2.2.6 Damages caused by operation beyond the parameters speci󽗉ed in applicable technical
speci󽗉cations.
2.2.7 Damages caused by unauthorized disassembly, alteration of products or modi󽗉cation of
software codes.
2.2.8 Damages caused by abnormal natural environment (force majeure, such as lightning,
earthquake, 󽗉re, storm, etc.).
2.2.9 Any damages caused by the process of installation and operation which unable to follow
the local standards and regulations.
2.2.10 Products beyond the warranty period.
2.3 Important Safety Matters
The following symbols may appear in this manual, which represent the following meanings:
Danger
Warning
Caution
Used to warn of urgent dangerous situations, if not avoided, it
could result in death or serious personal injury.
DescriptionSymbol
Used to warn of potentially dangerous situations, if not avoided, it
may result in death or serious personal injury.
Used to warn of potentially dangerous situations, if not avoided, it
may result in moderate or minor personal injury.
Attention
Used to transmit the safety warning information about equipment
or environment, if not avoided, it may cause equipment damage,
data loss, equipment performance degradation or other
unpredictable results. "Attention" does not involve personal
injury.
Note Used to highlight important information, best practices and tips,
etc.
2.4 Symbols Explanation
This chapter mainly elaborates the symbols displayed on the inverter, nameplate and packing
box.
2.4.1 Symbols on the Inverter
A fault occurred if the red light is on, please report it to the installer
or manufacturer as soon as possible.
DescriptionSymbol
Inverter running indicator.
Grounding symbol, the inverter casing needs to be properly
grounded.
2.4.2 Symbol on the Inverter nameplate
The inverter cannot be disposed of with household waste.
DescriptionSymbol
Please read the instructions carefully before installation.
Do not touch any internal parts of the inverter until 5 min after
being disconnected from the mains and PV input.
CE mark, the inverter complies with the requirements of the
applicable CE guidelines.
Danger. Risk of electric shock!
TUV certi󽗉cation.
The surface is hot during operation and no touch is allowed.
Electric shock hazard, it is strictly forbidden to use the person to
disassemble the inverter casing.

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Figure 3-1 400V output inverter applicable grid type
Figure 3-2 500V output inverter applicable grid type
Handle with care.
DescriptionSymbol
This side up.
Keep dry.
Stacked layers.
2.4.3 Symbol on the Packing box 3. Product Introduction
3.1 Basic Features
3.1.1 Function
The Sunways STT 80~125kW series is a three-phase grid-connected PV inverter which is used
to e󽗋ciently convert the DC power generated by the PV string into AC power and feed it into
the grid.
3.1.2 The STT 80~125kW series inverter contains 5 models which are list below:
· STT-80KTL, STT-100KTL, STT-110KTL
· STT-100KTL-HV, STT-125KTL-HV
3.1.3 Applicable grid type
The applicable grid types for the Sunways STT 80~125kW series are TN-S, TN-C, TN-C-S, IT and
TT. When applied to the TT grid, the voltage of N to PE should be less than 30V.
· STT-80KTL, STT-100KTL, STT-110KTL, connection mode see Figure 3-1 for details.
· STT-100KTL-HV, STT-125KTL-HV, connection mode see Figure 3-2 for details.
3.1.4 Storage conditions
1) Inverter must be stored in its original packaging.
2) The storage temperature should be in the range of -30 ° C and + 60 ° C , and the relative
humidity stored should be less than 90%.
3) If a batch of inverters needs to be stored, the height of each pile should be no more than 2
levels.

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3.2.2 Inverter side view, as shown in Figure 3-4:
680mm
975mm
LOGO Display
680mm
290mm
3.2.3 Inverter bottom view, as shown in Figure 3-5:
3.2.4 Inverter back view, as shown in Figure 3-6:
Back Rail
Back Rail
Back Rail
Back Rail
3.2 Appearance Introduction
3.2.1 Inverter front view, as shown in Figure 3-3:
Name
Plate
DC Switch (Optional) DC Switch (Optional)
DC Input Terminal Com Port
AC Output Terminal
290mm
DC Switch (Optional)
Figure 3-3 Front view
Figure 3-5 Bottom view
Figure 3-6 Inverter back view
Figure 3-4 Side view

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Item Indicator Status Description
1Power
Indicator
O󽗈 No input voltage detected or input voltage is too low.
Slow 󽗊ashing Inverter powered on, waiting for the grid connection.
Quick 󽗊ashing Inverter detected grid power and entered self-test status.
Always on Normal, grid-connected and power generated.
2Alarm
Indicator
Always on An alarm or fault is detected, and the display can view the speci󽗉c
fault information.
O󽗈 The inverter is running normally.
Slow 󽗊ashing The monitoring device is not connected to the router or is not
connected to the base station.
Quick 󽗊ashing The monitoring device is connected to the router or connected to
the base station but not connected to the server.
3OLED
Display
On Display the inverter operating information.
O󽗈 If the button pressed without any response, the screen is faulty or
not well connected.
4 Button Physical
button
Switch OLED display information and set parameters by short
press and long press.
3.3 Display Interface
Figure 3-7 Display interface
3.3.1 Display interface, as shown in Figure 3-7：
Figure 3-8 Packing list
3.4 Packing List
The packaging of the inverter includes the following accessories. Please check whether the
accessories in the packing box are complete at the 󽗉rst time when receiving the goods. See
Figure 3-8 for the packing list:
4. Product Installation
4.1 Selection of Installation Location
The Sunways STT 80~125kW series is designed with IP65 protection for indoor and outdoor
installations. When selecting an inverter installation location, the following factors should be
considered:
1)The object used for mounting the inverter must be strong and can withstand the weight of
the inverter for a long time.
2) The inverter needs to be installed in a well-ventilated environment.
3) Do not expose the inverter directly to strong sunlight to prevent the power derating due to
excessive temperature.
4) The inverter should be installed in a place with shelter to prevent direct exposure to sunlight
and rain.
5) Install the inverter at the eye level for easy inspection of screen data and further
maintenance.
6) The ambient temperature of the inverter installation location should be between -30 ° C and
60 ° C.
7) The surface temperature of the inverter can reach up to 75 ° C. To avoid risk of burns, do
not touch the inverter while it’s operating and inverter must be installed out of reaching of
children.
4.1.1 Recommended installation location of the inverter, as shown in Figure 4-1:
sunways
① STT 80KTL 16pcs / STT 100~125KTL 20pcs.
② This connector already pre-installed inside the inverter.
Note
Ring Spanner × 1
Back Bracket × 1 PV Terminal × 20
M10
Bracket Screw × 6
Monitoring Device
(Optional) × 1
Inverter × 1
Inspection
Report
User
Manual
Quick
Guide
User Manual × 1
Quick Guide × 1
Inspection Report × 1
6Pin Terminal × 2②①

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4.1.2 The requirements for inverter installation spacing are shown in Figure 4-2:
4.1.3 The installation angle of the inverter is recommended as shown in Figure 4-3:
Figure 4-2 Recommended installation space
Figure 4-3 Recommended installation angle
1500mm 1000mm
1000mm
500mm 500mm
500mm 500mm
x
4.2 Mounting the Inverter
4.2.1 Wall bracket installation
Dimensions of wall bracket, see Figure 4-4:
1) Use the inverter back bracket as the template to mark the position of 6 holes on installation
bracket.
2) Use an electrical driller with 12mm diameter bit to drill 6 holes on the installation bracket.
See Figure 4-5 for details:
Figure 4-4 Dimensions of wall bracket
Figure 4-5 Mark the hole position
12mm
Figure 4-1 Recommended installation location
Do not put 󽗊ammable and explosive articles around the inverter.
Warning
483mm
668mm
334mm 334mm
23mm
668mm
≥ 15°

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Figure 4-6 Fix the wall bracket
Figure 4-7 Mounting the inverter
3) Follow the instructions in the picture below to install the M10 assembling bolts (bolt, spring
washer, 󽗊at washer) and tighten the bolts with torque wrench in the torque of 35-40N.m, see
Figure 4-6 for details:
4) Lift up the inverter with both hands, hang the back rail on the 󽗉xed back bracket carefully,
see Figure 4-7 for details:
Handle
Handle
4.3.1 Inverter PV string connection
4.3.1.1 The following principles must be considered when making electrical connections to the
inverter:
1) Disconnect the AC breaker on the grid side.
2) All DC switches at the bottom of the inverter must be turned to the "OFF" position.
3) The number and type of the PV modules connected in series in each string in a same MPPT
must be same.
4) Make sure the maximum output voltage of each PV string does not exceed 1100V.
4.3.1.2 DC connector assembly procedure
1) Select the appropriate photovoltaic cable according to the table below:
2) Strip o󽗈 the DC cable insulation sleeve for 7 mm, as shown in Figure 4-8:
Cable type Conductor cross-setional area (mm²)
General photovoltaic cable
Scope (mm²) Recommended value
(mm²)
2.5-4.0 4.0
Figure 4-8
Wire cross-setional area 2.5-4mm27mm
4.3 Electrical Connection
Danger hint
A high voltage in the conductive part of the inverter may cause an electric
shock. When performing any installation on the inverter, make sure that the AC
and DC sides of the inverter are completely de-energized.
Do not ground the positive or negative pole of the PV string, otherwise it will
cause serious damage to the inverter.
Static may cause damage to the electronic components of the inverter. Anti-
static measures should be taken during the repairing or installation.
Do not use other brands or other types of PV terminals other than the PV
terminals in the accessory package. Sunways has the right to refuse all
damages caused by the mixed-use of terminals.
Moisture and dust can damage the inverter, ensure the cable gland is securely
tightened during installation. The warranty claim will be invalided if the inverter
damaged by the cable connector not well installed.
Danger
Warning
Attention
Attention
Warning

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Crimping Plier
Figure 4-9
Figure 4-11
3) Disassemble the connector in the accessory bag, as shown in Figure 4-9:
5) Insert the positive and negative cables into the corresponding positive and negative
connectors and pull back the DC cable to ensure that the terminal is tightly attached in the
connector.
6) Screw the nut to the end with some power and ensure the terminal is well sealed, as
shown in Figure 4-11:
Figure 4-10
4) Insert the DC cable through the DC connector nut into the metal terminal and press the
terminal with a professional crimping plier (pull back the cable with some power to check if
it’s tight enough), as shown in Figure 4-10:
+
-
Model Inverter Rated
Output Voltage
AC Breaker
Rated Voltage
AC Breaker
Rated Current
STT-80KTL 400V 400V 160A
STT-100KTL 400V 400V 200A
STT-110KTL 400V 400V 200A
STT-100KTL-HV 500V 690V 160A
STT-125KTL-HV 500V 690V 200A
4.3.2 Connection of AC output
Before connecting to the power grid, make sure that the power grid voltage and frequency
meet the requirements of the inverter. See technical parameters for details.
1) AC circuit breaker
The rated output voltage of Sunways STT series 80~125kW three-phase inverter and the
recommended circuit breaker speci󽗉cations are shown in the table below:
2) Requirements for OT/DT terminal
OT/DT terminals (not included in the delivery scope) are required for 󽗉xing AC cables to the
terminal block. Purchase the OT/DT terminals according to the following requirements.
Figure 4-12
7) Insert the positive and negative connectors into the inverter DC input terminals respectively,
and a "click" sound represents the assembly in place, as shown in Figure 4-12:
8) Seal the unused PV terminals with the terminal caps.
1.Before assembling the DC connector, make sure that the cable polarity is
correct.
2.Use a multimeter to measure the voltage of the DC input string, verify the
polarity of the DC input cable, and ensure that each string voltage is within
1100V.
Warning
An AC breaker must be connected on the AC side of the inverter.
Any loads cannot be directly connected to the inverter.
Warning
Open-end Wrench
OT / DT terminals of phase wire OT / DT terminals of PE wire
Speci󽗉cation M10 M6
Dimensions a ≤ 36mm / 11mm ≤ b ≤ 15mm / c ≤ 20mm /

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Figure 4-17
Figure 4-18
3) Put the AC cable through the cable gland and use a socket spanner to lock all cables to the
correspondingly AC connector and pull back them with some power to make sure they’re well
connected. As shown in Figure 4-17:
4) Insert the 󽗊at cable of the display back to its place and put back the right roof cover and
lock with its original screws. As shown in Figure 4-18:
Figure 4-16
2) Put the cable through the cable gland, and strip o󽗈 the outer insulation sheath ≤ 160mm,
according to the size of OT/DT terminals to peel o󽗈 a proper length of the 3L /PE / N wires, then
insert the conductor core into the OT/DT terminals and press with a hydraulic clamp. As shown
in Figure 4-16:
≤ 160mm
Strip Length:L
L
Outside Diameter:30~45mm
L1
L2
L3
PE
N
4.3.2.1 AC connector connection steps
1) Take out the ring spanner from the accessory box and remove the right roof cover after
unscrewed the screws on it, as shown in Figure 4-15:
Figure 4-15
3) Aluminium cable requirements
If an aluminium cable is selected, use a copper to aluminium adapter terminal to avoid direct
contact between the copper bar and the aluminium cable.
Direct contact between the copper bar and aluminium wire may arise
electrochemical corrosion, thus a󽗈ect the reliability of the electrical connection.
If an aluminium wire is used, please use a copper-aluminium wire terminal to
avoid direct contact between the copper bar and aluminium wire.
Caution
Figure 4-14
a b
c
Figure 4-13 OT / DT terminals of phase wire

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Ground terminal connection steps:
1) The external grounding terminal is located in the lower right side of the inverter.
2) Fix the grounding terminal to the PE wire with a hydraulic clamp and lock the grounding
terminal to the grounding hole in the inverter. As shown in Figure 4-19:
Figure 4-19 Grounding terminal connection
4.3.3 External ground connection
Do not connect the N-wire as a protective ground wire to the inverter casing.
Otherwise, it may cause electric shock.
Good grounding is good for resisting surge voltage shock and improving EMI
performance. Inverters must be well-grounded.
For a system with only one inverter, just ground the PE cable.
For a multi-inverter system, all inverters PE wire need to be connected to the
same grounding copper bar to ensure equipotential bonding.
Danger
Attention
Figure 4-20 Monitoring device installation
4.5 RS485/DRED Connection
4.5.1 Terminals de󽗉nition
Inverter communication ports are located at the ARM board inside of the inverter and include
RS485 port (used for Meter or Datalogger connection), DRED port, and display port, as shown
in Figure 4-21:
1.The GPRS version module does not need to be con󽗉gured.
2.The WiFi version module needs to be con󽗉gured to the router for the 󽗉rst
installation, and if the router name or password changed, you need to con󽗉gure
it again. For details, please refer to the [QUICK INSTALLATION GUIDE] which
attached in the accessory bag.
Don't touch the waterproof plug in the card slot unless replace the SIM card. If
the SIM card needs to be replaced, please make sure the card slot is completely
sealed by waterproof plug after replacing. Any damages caused by the
waterproof plug sealing problem will be invalid of warranty.
Attention
Note
4.4 Monitoring Device Installation
Sunways STT 80~125kW series three-phase inverter supports WiFi, GPRS and RS485
communication, you can choose any of them according to your needs.
Plug the WiFi or GPRS module into the COM port in the bottom of inverter by following the
direction that the side with indicator is up (as shown in Figure 4-20). A slight “click” sound
during the installation represents that the assembly is in place.
If there’re more than one inverter in a project, do not open all inverters roof
cover at the same time if you cannot 󽗉nish the AC connection immediately.
Any damages caused by the moisture and dust that came into the inverter on
account of exposed to the air for a long time are out of Sunways warranty.
Attention

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Figure 4-21
Figure 4-22 Terminals de󽗉nition
1 13 35 5
2 24 46 6
Port 1 Port 2 Port 3
Port 4
Port Function NO. De󽗉nition
Port 1
Connect data logger in a daisy chain mode through RS485
protocol to realize monitoring or the anti-reverse function on
multi-inverter.
1RS485 A1
2RS485 B1
3PE
4RS485 A1
5RS485 B1
6PE
Port 2 Connect external Meter to realize the anti-reverse function on
single unit Sunways STT series inverter.
1RS485 A2
2RS485 B2
3PE
4NULL
5NULL
6NULL
Port 3 Connect inverter display board. / /
Port 4
DRED means demand response enable device. The AS/NZS
4777.2:2015 requires inverters to support demand response
mode (DRM). This function is for inverter that comply with AS/
NZS4777.2:2015 standard.
Sunways inverter is fully complied with all DRM. The 6pin
connector is used for DRM connection.
Support DRM command: DRM0, DRM5, DRM6, DRM7, DRM8.
/
4.5.2 RS485 Communication
STT 80~125kW series three-phase inverter supports multiple inverters connection to a
Sunways data logger in a daisy chain mode through RS485 protocol. Customers can check
their inverters real-time power, warnings and status through the App"SunwaysHome"or
Sunways monitoring system (monitor.sunways-tech.com) anytime anywhere.
Multiple inverters connection diagram as shown in Figure 4-23:
STT 80~125KTL
series inverter STT 80~125KTL series inverter STT 80~125KTL series inverter
Data logger
Sunways server
InternetInternet
RS485 RS485 RS485
Router
Figure 4-23 Multiple inverters connection diagram
...
If there're multiple inverters in a project, connect them in a daisy chain mode through RS485
communication. The 120 Ω terminal resistor of the dip switch SW2 in the inverter at the end
of the daisy chain needs to be switch to the “ON” position (default is “OFF”), and the shielded
layer of the communication cable should be single-point grounding. As shown in Figure 4-24:
Figure 4-24
SW2

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Figure 4-25 RS485 communication port schematic diagram
14 2 53 6
RS485 cable requirements: Shielded twisted-pair cable or shielded twisted
Ethernet cable.
Attention
5. Start and Stop
5.1 Inverter start-up
When starting the inverter, follow these steps:
1) Turn on the AC breaker 󽗉rst.
2) Turn on the three DC switches in the bottom. If the PV string voltage higher than the inverter
start-up voltage, the inverter will start.
3) When both AC and DC power supply are normal, the inverter is ready to start. The inverter
will initiate from checking its internal parameters and grid parameters, if it’s within the range,
the green light on the left side of the screen begins to 󽗊ash, and the “Waiting” message will be
displayed on the OLED display.
4) After self-checking completed, the inverter will start generating electricity, the green light
will remain on, and the OLED display will display real-time power information.
5.2 Inverter shutdown
When turning o󽗈 the inverter, please follow the steps below:
1) Turn o󽗈 the AC breaker 󽗉rst.
2) Wait 30 seconds and then turn the three DC switches to the “OFF” position. At this time,
there is remaining power in the inverter capacitor. Wait for 5 minutes until the inverter is
completely de-energized before operating.
3) Disconnect the AC and DC cables.
4.5.3 Anti-reverse or power limit solution
Anti-reverse or power limit solution, wiring instructions and con󽗉guration, please contact
Sunways after-sales at [e-mail].
4.5.4 RS485/DRED connection steps:
1) Remove the right roof cover of the inverter with a cross screwdriver.
2) Put the cables which you need through the cable gland, as shown in Figure 4-25:
3) Insert the cable to the port in the 6pin connector and fasten with a screwdriver.
4) Insert the 6pin connector into the 6pin connecter inside the inverter, and screw the roof
cover back with a cross screwdriver.
The maximum distance between the inverter at the end of the daisy chain and the data logger
should be within 1000M.
Suggest using the RS485 communication cable with a cross-sectional area
of 0.75-1.5mm² and an outer diameter of 5mm-10mm.
RS485 cable requirements: Shielded twisted-pair cable or shielded twisted
Ethernet cable.
Attention
Suggest to use the communication cable with the cross-sectional area of 0.75-1.5mm² and
outer diameter of 5mm-10mm.

28 29
6.2 Auto-Test
This function is disabled by default, and only will be functional in the safety code of Italy.
Short press the button several times until “Auto Test CEI 0-21” displays on the screen, press
and hold the button 3 seconds to activate “Auto Test”. After the auto test 󽗉nished, short press
the button several times until the screen displays “Auto Test Record”, and hold the button 3
seconds to check the test result.
The auto test type will be chosen from “Remote” and “Local” before starting the auto test.
“Remote” is set as 1 by default, which only can be modified to “0” by sending an external
command and “Local” is set as 0 by default, which can be modi󽗉ed to 1 through operating
the button on the inverter. According to the requirements of the standard, the test has been
divided into three modes:
1) “Remote” set as 1, “Local” set as 0, then the test order is 59.S1，59.S2，27.S1，81>.S2，81<.S2;
2) “Remote” set as 1, “Local” set as 1, then the test order is 59.S1，59.S2，27.S1，81>.S1，81<.S1;
3) “Remote” set as 0, “Local” set as 1, then the test order is 59.S1，59.S2，27.S1，81>.S2，81<.S2.
Connect the AC cable, auto test will start after the inverter connected to the grid, see the
operation steps below:
The auto test will start when the correct test item is selected, and the test result will be
displayed on the screen when it finished. If the test success, it will display “Test Pass”,
otherwise will display “Test Fail”. After each item tested, the inverter will reconnect to the grid
and automatically start the next test item according to the requirements of CEI 0-21.
Remote Cmd
1
Select
Items Wait
Wait
Wait
Wait
Wait
General
Settings
Auto Test
CEI 0-21
Main Windows
IPS Item
xxxxx
Test Record
If
Tested
Test Result
Display
Local Cmd
0
IPS Item
Test Null
Password
1111
Verify Ok
Password
1111
Setting
IPS Item
Test All
IPS Item
Testing Test Pass/Fail
Short press(1s), switch window
Long press(3s), enter the
lower Menu
6. General Operation
6.1 Display Operation
When the inverter is turned on, the following interfaces will be displayed on the OLED display,
and you can check the information and modify the parameters of the inverter by short or long
pressing the button. Please refer to the following display operation 󽗊ow for details:
Tip: After every setting completed, wait for 10 seconds and the inverter will
automatically save your settings or modi󽗉cations.
Short press(1s), switch window
Long press(3s), enter the
lower Menu
Firmware
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7.2 Maintenance
Risk of inverter damage or personal injury due to incorrect service!
Always keep in mind that the inverter is powered by dual sources: PV strings
and utility grid.
Before any service work, observe the following procedure.
1. Disconnect the AC circuit breaker and then set the DC load-break switch of
the inverter to OFF;
2. Wait at least 5 minutes for inner capacitors to discharge completely;
3. Verify that there is no voltage or current before pulling any connector.
Keep non-related persons away!
A temporary warning sign or barrier must be posted to keep non-related
persons away while performing electrical connection and service work.
Restart the inverter only after removing the fault that impairs safety
performance.
As the inverter contains no component parts that can be maintained, never
arbitrarily replace any internal components.
For any maintenance need, please contact Sunways. Otherwise, Sunways shall
not be held liable for any damage caused.
Servicing of the device in accordance with the manual should never be
undertaken in the absence of proper tools, test equipment or the latest revision
of the manual which has been clearly and thoroughly understood.
Attention
Note
Danger
Caution
Items Methods Period
System clean
Check the temperature and dust of the inverter.
Clean the inverter enclosure if necessary.
Check if the air inlet and outlet are normal.
Clean the air inlet and outlet if necessary.
Six months to a year (it depends on
the dust contents in air.)
7. Troubleshooting
7.1 Fault Messages
Sunways STT 80~125kW series three-phase inverter is designed in accordance with grid
operation standard, and conform to the requirements of the safety and EMC. The inverter had
passed a series of rigorous tests to ensure it runs sustainably and reliably before shipment.
When a fault occurs, the corresponding fault messages will display on the OLED display, and in
this case, the inverter might stop feeding into grid.
The fault messages and their corresponding troubleshooting methods are listed below:
Error Message Troubleshooting
No Display 1. Check whether cables are all 󽗉rmly connected and DC switch is on.
2. Check whether the input voltage meets the working voltage.
Mains Lost 1. Check whether the mains supply is lost.
2. Check whether the AC breaker and terminals are well connected.
Grid Voltage Fault
1. Check whether the safety regulation setting is correct.
2. Check the voltage of the grid. If the grid voltage exceeds the allowed range of
inverter protection parameters, please contact the local grid company to resolve.
3. Check whether the impendence of the AC cable is too high to lead the grid
voltage increased. Change a thicker AC cable if it is.
Grid Frequency Fault
1. Check whether the safety regulation setting is correct.
2. Check the frequency of the grid. If the grid frequency exceeds the allowed range
of inverter protection parameters, please contact the local grid company to resolve.
ISO Over Limitation
1. Check whether the PV panels, cables, and connectors are broken or water
leaked.
2. Check whether there is a reliable inverter grounding line.
GFCI Fault 1. The ground current is too high.
2. Check whether the PV cable has a short circuit to ground.
PV Over Voltage
1. Input voltage is too high.
2. Reduce the number of PV panels to make sure the open-circuit voltage of each
string is lower than the inverter max allowed input voltage.
Inverter Over
Temperature
1. Check whether the inverter is direct exposure to the sunlight.
2. Reduce ambient temperature.
DCI Fault
1. Restart the inverter, wait a moment for inverter recovery.
2. If the fault occurs repeatedly, please contact Sunways.
Bus Voltage Fault
SCI Fault
SPI Fault
E2 Fault
GFCI Device Fault
AC Transducer Fault
Relay Check Fail
Flash Fault
Fan Fault 1. Stop the inverter and disconnect the AC&DC cables.
2. Check whether the fan is blocked by foreign matters. If not, replace the fan.

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Model STT-80KTL STT-100KTL STT-110KTL STT-100KTL-HV STT-125KTL-HV
E󽗋ciency
Max. E󽗋ciency 98.8% 98.8% 98.8% 98.8% 98.8%
European E󽗋ciency 98.3% 98.3% 98.3% 98.3% 98.3%
MPPT E󽗋ciency 99.9% 99.9% 99.9% 99.9% 99.9%
Protection
DC Reverse Polarity Protection Integrated
Insulation Resistance Protection Integrated
DC Switch Optional
Surge Protection Integrated (Type Ⅱ )
Over-temperature Protection Integrated
Residual Current Protection Integrated
Anti-islanding Protection Frequency shift, Integrated
AC Short-circuit Protection Integrated
AC Over-voltage Protection Integrated
PID Protection Optional
General Data
Dimensions (mm) 975W*680H*290D
Weight (kg) 79 82
Protection Degree IP65
Self-consumption at Night (W) < 1
Topology Transformer-less
Operating Temperature Range (° C) -30~60
Relative Humidity 0~100%
Operating Altitude (m) 3000
Cooling Smart Fan Coolling
Display OLED & LED
Communication RS485, WiFi/GPRS/LAN (Optional)
Compliance NB/T32004、IEC62109、IEC62116、IEC61727、IEC60068、
IEC61683、EN50549、EN61000
Model STT-80KTL STT-100KTL STT-110KTL STT-100KTL-HV STT-125KTL-HV
DC Input
Start-up Voltage (V) 200 200 200 200 200
Max. DC Input Voltage (V) 1,100 1,100 1,100 1,100 1,100
Min. DC Voltage (V) 180 180 180 180 180
Rated DC Input Voltage (V) 620 620 620 750 750
MPPT Voltage Range (V) 200~950 200~950 200~950 200~950 200~950
Full Power MPPT Voltage Range (V) 400~850 400~850 440~850 400~850 500~850
No. of MPP Trackers 8 10 10 10 10
No. of DC Inputs 16 20 20 20 20
Max. Input Current (A) 8*26 10*26 10*26 10*26 10*26
Max. Short-circuit Current (A) 8*40 10*40 10*40 10*40 10*40
AC Output
Rated Output Power (kW) 80 100 110 100 125
Max. Output Power (kW) 88 110 121 110 137.5
AC output rated apparent
power (kVA) 80 100 110 100 125
Max. Apparent Power (kW) 88 110 121 110 137.5
Rated Output Voltage (V) 3L/N/PE, 230/400V 3L/N/PE, 288/500V
Rated AC Frequency (Hz) 50/60
AC output rated current (A) 115.5 144.3 158.8 115.5 144.3
Max. Output Current (A) 127 158.8 174.8 127 158.8
The measured Inrush current (A) [email protected] [email protected] [email protected] [email protected] [email protected]
Maximum output fault current (A) 300 300 300 300 300
Maximum output overcurrent
protection (A) 300 300 300 300 300
Power Factor 0.8 leading …0.8 lagging
Max. Total Harmonic Distortion < 3% @Rated Output Power
DCI < 0.5%In
8. Technical Parameters

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S11-00021-00
Address: No. 1, Second Road, Green Industrial Zone, Chongshou Town,
Cixi City, ZheJiang Province, PEOPLE’S REPUBLIC OF CHINA
Website: www.sunways-tech.com
Service Mail: [e-mail]
Hotline: [phone]