ABB UNO-7.6-TL-OUTD-S-US-A User manual

ABB solar inverters
Product manual
UNO-7.6-8.6-TL-OUTD-S-US-A
(7.6 to 8.6 kW)

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001CV
IMPORTANT SAFETY INSTRUCTIONS
This manual contains important safety instructions that must be followed during installation
and maintenance of the inverter.
SAVE THESE INSTRUCTIONS!
Keep this document in a safe place near the inverter for easy access during installation and
maintenance.
THE INSTALLER MUST READ THIS DOCUMENT IN ITS ENTIRETY BEFORE
INSTALLING OR COMMISSIONING THIS EQUIPMENT.
The purpose of this document is to support the qualied technician, who has received training
and/or has demonstrated skills and knowledge in construction, to install and maintain this inverter.
This manual does not cover any details concerning equipment connected to the inverter such
as the solar modules. Information concerning the connected equipment is available from the
respective manufacturers.
Warranty conditions can be found on the UNO product page of the website. NOTE: Any
changes or modications not approved by the responsible party could void the user authority
to operate the equipment.
FCC REMARKS
The equipment has been tested and found to comply with the limits for a Class B digital
device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference in a residential installation. This equipment generates,
uses and can radiate radio frequency energy and, if not installed and used in accordance with
the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation. If
this equipment does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver
is connected.
• Consult the dealer or an experienced radio/TV technician for help.

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001CV
Product Manual
UNO-7.6-8.6 string inverters
1 - Introduction and safety
2 - Installation location
3 - Mounting and wiring
4 - Operations
5 - Troubleshooting
6 - Maintenance
7 - Appendix
UNO-7.6-8.6-TL-OUTD-S-US-A Product Manual
BCG.00751.0_AA Rev 1.1
© Copyright 2014 ABB. All Rights Reserved.

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002TC
Contents
Introduction and safety ...................................................................................................................... 7
Warnings in this document ...................................................................................................................7
Equipment safety warnings.................................................................................................7
General installation warnings..............................................................................................8
Assembly warnings ..............................................................................................................8
Electrical connection warnings...........................................................................................8
Safety instructions .................................................................................................................................9
General information..............................................................................................................9
Thermal and voltage hazards ..............................................................................................9
Clothing and protective devices .........................................................................................9
Location of safety notices and labels...............................................................................10
Appropriate usage................................................................................................................................11
Conditions of use................................................................................................................11
Environmental conditions..................................................................................................11
Improper or prohibited use................................................................................................11
Arc fault detection (AFD) .....................................................................................................................12
Available models ..................................................................................................................................12
Regulatory nameplate ........................................................................................................13
Installation location .......................................................................................................................... 15
Transportation and handling...............................................................................................................15
Incoming inspection.............................................................................................................................15
Select the installation location............................................................................................................17
Environmental check..........................................................................................................17
Installation position ............................................................................................................18
Mounting and wiring ....................................................................................................................... 21
Labeled illustration of UNO inverter...................................................................................................21
Wall mounting .......................................................................................................................................23
Wiring details ........................................................................................................................................25
Wiring box components.....................................................................................................26
Electrical connection to the PV field - DC side .................................................................................27
Independent or parallel configuration of inputs..............................................................27
Installing jumpers for parallel configuration ...................................................................28
UNO 8.6kw - External string combiner with single MPPT input ...................................30
Optional DC fused inputs...................................................................................................31
Grid output connection (AC side).......................................................................................................34
Connection to AC terminal block ......................................................................................35
Grid standard setting of the country ................................................................................35
Communication card connections .....................................................................................................36
Opening the hinged inverter cover...................................................................................36
Serial communication connection (RS-485) ....................................................................37
D aisy chain units for connection to a monitoring system ............................................39
Addressing each inverter...................................................................................................40
Monitoring system via serial (RS-485)..............................................................................40
Optional monitoring system via RADIOMODULE ...........................................................40
Configurable relay connection (Alarm) ............................................................................41
Remote control connection ...............................................................................................41

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002TC
Operations........................................................................................................................................ 43
Monitoring and data transmission .....................................................................................................43
Types of data available ......................................................................................................43
User interface........................................................................................................................................43
Display and keypad ............................................................................................................44
LED indicators.....................................................................................................................45
Descriptions of symbols and display fields ....................................................................46
Cyclical display of general information............................................................................47
Statistics menu ...................................................................................................................48
Settings menu .....................................................................................................................49
Information Menu................................................................................................................58
Zigbee Menu ........................................................................................................................59
Commissioning.....................................................................................................................................60
Configure inverter settings................................................................................................60
Power ON the inverter ........................................................................................................61
Dynamic behavior of the display during operation ........................................................62
Troubleshooting............................................................................................................................... 63
Arc fault detection self-test errors......................................................................................................63
Obtaining the service level password................................................................................................64
Display messages and error codes ...................................................................................................64
Making a service call............................................................................................................................75
Maintenance..................................................................................................................................... 77
Power-down procedure .......................................................................................................................77
Routine maintenance ...........................................................................................................................78
Other maintenance .............................................................................................................78
Installing a replacement inverter chassis..........................................................................................79
Removing the old inverter chassis from the switchbox ...............................................80
Installing the replacement inverter chassis.....................................................................81
Storage and dismantling .....................................................................................................................83
Appendix........................................................................................................................................... 85
System description .............................................................................................................................85
Protective devices within the inverter................................................................................................86
Topographic diagram of the equipment ............................................................................................87
Efficiency curves ..................................................................................................................................88
Voltage and temperature derating due to altitude ............................................................................89
Automatic power reduction.................................................................................................................91
Technical data and types.....................................................................................................................93

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002TC

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003CH1
Warnings in this document
This is a list of special safety symbols used in this manual that highlight potential safety risks and/or useful
information. The symbol usage is described below:
CAUTION
The reader should stop, use caution and fully understand the operations
explained before proceeding.
DANGEROUS VOLTAGE
The product works with high voltages. All work on the UNO inverter must
follow the described documentation and must comply with all prevailing
codes and regulations associated with high voltages.
HOT TEMPERATURE
Some surfaces may become hot; do not touch the product while it is in
operation.
UL1741 Standard for Safety for Inverters, Converters, Controllers and
Interconnection System Equipment for use with Distributed Energy
Resources. CSA-C22.2 No. 107.1-01 - General Use Power Supplies.
Equipment safety warnings
In addition to the safety and hazard symbols, the following symbols are also used in this
installation guide
System earth conductor (equipment ground, protective earth)
Alternating current (AC) øPhase
Direct current (DC) Grounding (earth)
1
Introduction and safety

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004CC1
1- Introduction and safety
General installation warnings
The UNO transformerless inverter is designed and tested according to international safety
requirements (UL1741/IEEE1547); however, certain safety precautions must be observed
when installing and operating this inverter.
All operations regarding transport, installation start up, and maintenance, must be
carried out by qualied, trained personnel and in compliance with all prevailing local
codes and regulations.
Assembly warnings
Prior to installation, inspect the unit to ensure absence of any transport or handling damage,
which could affect insulation integrity or safety clearances; the failure to do so could result in
safety hazards.
Assemble the inverter per the instructions in this manual. Use care when choosing the
installation location and adhere to specied cooling requirements. Unauthorized removal of
necessary protection features, improper use, incorrect installation or operation may lead to
serious safety and shock hazards and/or equipment damage.
Electrical connection warnings
This grid-tied inverter system operates only when properly connected to the AC utility grid.
Before connecting the UNO grid-tied inverter to the AC utility grid, contact the local power
distribution company to receive the appropriate approvals. This connection must be made
only by qualied technical personnel.
Wiring methods used should be in accordance with the National Electric Code,
ANSI/NFPA 70 and/or any prevailing local codes and regulations.
All photovoltaic source and output circuit conductors MUST have disconnects
complying with the NEC, Section 690, Part III. All models listed in this manual
include an integrated DC disconnect switch.
Output circuits must be isolated from the enclosure. System grounding,
required by Sections 690.41 - 690.43 of the National Electric Code, ANSI/NFPA
70, is the responsibility of the installer.
Connect only to a dedicated branch circuit provided with the maximum branch
Over Current Protection Device (OCPD) in accordance with the CSA document
available online and listed on the technical data sheet found in the appendix,
section 7.

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004CC1
1- Introduction and safety
Safety instructions
These servicing instructions are for use by qualied personnel only. To reduce the risk of electric shock, do not
perform any servicing other than that specied in the operating instructions.
Be sure all ammable materials including construction items are away from the unit. Do not install the inverter
in or near potentially explosive areas.
The installer and/or operator must properly protect the installation from access by the public and/or highlight
with signs or notices the potential hazards of the equipment, e.g., magnetic elds, hazardous voltages, high
temperatures, possibility of discharges, generic hazard, etc..
General information
The equipment has been manufactured in accordance with the strictest accident-prevention
regulations and supplied with safety devices suitable for the protection of components and
operators. Inform ABB about non-standard installation conditions.
The instructions given in the manual do not replace the information and warnings on the
safety labels mounted on the product. They do not replace the safety regulations enforced
in the country of installation.
Do not use the equipment if any operating anomalies are found. All repairs should be
carried out using only qualied spare parts, which must be installed in accordance with their
intended use and by a licensed contractor. Liabilities arising from commercial components
are delegated to their respective manufacturers.
Thermal and voltage hazards
Depending upon ambient temperatures during operation and immediately
following shut down, surface temperatures on the cooling ns (heat sink) and
some areas of the chassis may be extremely hot to the touch.
Prior to touching any part of the inverter use care to ensure surfaces and equipment are at
touch-safe temperatures and voltages before proceeding.
Anytime the inverter has been disconnected from the AC utility grid, use extreme caution as
some components can retain charge sufcient to create a shock hazard and may need at
least ve minutes to dissipate the charge. To minimize occurrence of such conditions, comply
with all corresponding safety symbols and markings present on the unit and in this manual.
Clothing and protective devices
Appropriate Personal Protective Equipment (PPE) must be worn at all times when servicing
this equipment under any conditions which may subject personnel to hazardous voltages or
temperatures that are not touch-safe. All operations on the equipment should be performed
with properly electrically insulated instruments.

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004CC1
1- Introduction and safety
Location of safety notices and labels
Note the location of safety notices on the inverter for notication and protection. Labels must
not be hidden with external objects or parts such as rags, boxes, or other such equipment.
They should be cleaned periodically and always maintained in view.
-
W ARNING
Risk of electrical shock. Hazardous voltage will
cause severe injury or death.Nouser ser viceable
parts inside. Only trainedservice personnel are
allowedaccess.
Risk of electric shock from energy stored in
capacitors. Wait 5minutesafterdisconnecting all
sourcesofpowertoremovecover.
Both AC and DC voltagesources are terminated
inside this equipment.Each circuit must be
disconnected beforeser vicing.
Whenthephotovoltaic array is exposedtolight,it
suppliesDCvoltagetothisequipment.
Electric shock hazard. The DC conductoofrsthis
photovoltaic systemare ungroundedandmay be
energized.
Electric Shock Hazard. The DC conductors of this
photovoltaic systemarenormallyungroundedbut will
become intermittently grounded without indication
whentheinvertermeasuresthe PVarrayisolation.
Hot surfaces. To reduce the risk of burns do not
touchheatsinknorthesides oftheinverter.
Integral DC Ground Fault Detector/Interrupter
Protection provided. Risk of Electric Shock.
Normally Grounded Conductors May Be
Ungrounded and Energized When a
Ground-Fault is Indicated.
Left side view Right side view
UNO-7.6-TL-OUTD-S-US
P/N:3N209940US0
WO:1636209
SO:S00000000 Q1
SN:1350667651 WK:5013
UNO-7.6-TL-OUTD-S-US
P/N:3N209940US0
WO:1636209
SO:S00000000 Q1
SN:1350667651 WK:5013
UL 1741
CSA-C22.2 No. 107.1-01
C US
®
Country of Origin Italy
www.abb.com/solar
SOLAR UTILITY INTERACTIVE
TRANSFORMERLESS INVERTER
MODEL:UNO-7.6-TL-OUTD-S-US-A
This devicecomplieswithPart 15 of theFCC Rules. Operationis subjectto thefollowingtwo
conditions:(1) this device may not cause harmful interference,and (2) this device must accept
any interference received,including interference that may cause undesidered operation.
For more details about product specications refer to the Instruction Manual
1 2
( ): Adjustable from 57.0 Hz to 59.8 Hz ( ): Adjustable from 60.2 Hz to 63.0 Hz
Nominal Input OperatingVoltage
Max.InputVoltage
Range of Input OperatingVoltage
Range of InputVoltage @Full Power
Max.Input Current
Max. Input Short Circuit Current (P.V. Panels)
DC RA TING
Nominal OutputVoltage
OperatingVoltage Range
Nominal Output Frequency
Operating Frequency Range
Output Power Factor
Max.Output Current
AC RA TING
Max.Continuous Output Power
Max.Output Overcurrent Protection
2 x 24A
2 x 30A
380V
600V
90 - 580 V
200 - 480V
60 Hz (factory preset)
1 2
59.3 ( ) - 60.5 ( ) Hz
>0.995
27.6 A / 32A / 36.5A (rms)
277V~ / 240V~ / 208V~ 1Ø
40 A / 40A / 50A
7600W @ 50°C amb.
244-304 V~/211-264V~/183-228V~
DC Ground Fault Detector/Interrupter is Provided
PhotovoltaicArc-Fault Circuit Protection -Type 1
Type ofEnclosure: NEMA4X
OperatingAmbient Temperature: -25 to+60 °C (-13 to +140 ° F), withOutput Power Derating

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004CC1
1- Introduction and safety
Appropriate usage
The UNO Inverter is a photovoltaic inverter that converts direct current of a connected PV array into alternating
current and feeds that power into the AC utility grid.
This inverter is designed for outdoor use, but can be used indoors if installed to specied environmental and
mounting parameters stated in this manual, and adherence to the National Electric Code. See environmental
conditions below and environmental check in section 2.
Conditions of use
This inverter utilizes a transformerless design and requires connected arrays to be
oating with respect to ground; it can be used only with photovoltaic modules that do
not require one of the terminals to be grounded.
• The DC and AC operating currents MUST NOT exceed the limits documented in the
technical specications found in the data table in the appendix, section 7.
• The inverter is certied for use only with photovoltaic arrays connected to its input
channel(s). Do not connect batteries or other types of power sources.
Environmental conditions
Adverse environmental conditions can lead to a reduction in performance. The equipment
should be installed outdoors, but only in environmental conditions indicated in this manual.
Care must be taken to provide adequate ventilation if installed indoors.
Improper or prohibited use
The following actions are dangerous and not consistent with acceptable practice under the
terms of the warranty:
• Installing the equipment in environments with ammable conditions.
• Using the equipment with safety devices not working or disabled.
• Using the equipment or parts of the equipment by connecting it to other machines or
equipment, unless otherwise expressed.
• Modifying areas that are operator restricted and/or altering parts of the equipment in
order to vary the performance or change its protection.
• Cleaning with corrosive products that may corrode parts of the equipment or with products
that might generate electrostatic charges.
• Using or installing the equipment or parts of it without having read and correctly interpreted
the contents of this manual.
• Blocking airow to the cooling ns (e.g., warming or drying rags) on the unit or accessory
parts is dangerous and could compromise the inverter operation.

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004CC1
1- Introduction and safety
Arc fault detection (AFD)
The 2011 National Electric Code (NEC) and 2013 Canadian Electric Code (CEC) include a condition that
requires a photovoltaic system with a DC voltage greater than 80V, and which is on a building or whose DC
conductors enter a building, be equipped with a Listed device which can detect a DC arc fault and interrupt the
circuit. This functionality is commonly referred to as a DC AFCI.
The UNO inverter DC ARC FAULT DETECTION (AFD) solution is based on Digital Signal Processor (DSP)
technology. The AFD module has two independent channels, designed to accommodate the two independent
MPPT channels associated with all UNO string inverters, and has two current sensors and associated circuitry
to identify the presence of a series DC arc fault at the input of either inverter MPPT channel.
The AFD module performs a self-test every time the system is started and the inverter display shows the result,
which can only be pass or fail. If it fails, an error code will be displayed and the inverter will not connect to the
grid. If it passes, the inverter connects and operates normally.
If a DC arc fault is detected during normal operations, the inverter disconnects from the AC grid. The DC arc
fault error is indicated on the inverter display screen and lock out of inverter operation is initiated until the fault
is Manually Reset.
Refer to section 5 for display error messages and instructions to reset fault conditions
or manually start the self-test procedure.
Available models
The inverters are divided into two models according to their rated output power of 7.6 kW or 8.6 kW.
Both models include an integrated DC disconnect switch and a built-in PV AFCI Type 1 device for arc fault
detection (DC AFD) and are equipped with 2 DC inputs per MPPT channel using non-fused terminal blocks.
The wiring box is designed with room to accommodate three fused DC inputs per MPPT channel resulting in a
total of six fused inputs (12 fuses and 12 fuse holders, considering positive and negative inputs). See Optional
DC fused inputs in section 3.
7.6 Kw UNO-7.6-TL-OUTD-S-US-A
Unit Weight – 82 lbs/ 37 KG
Dimensions (H x W x D) – INVERTER ONLY:
18.9 x 22.9 x 8.8 in (480 x 620 x 225mm)
INCLUDING DC SWITCH WIRING BOX:
29.3 x 22.9 x 8.8 (745 x 620 x 225mm)
8.6 Kw UNO-8.6-TL-OUTD-S-US-A

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004CC1
1- Introduction and safety
POWER ALARM GFI ESC UP DOWN ENTER
UNO
Regulatory nameplate
Technical data in this manual does not supersede the data on the labels afxed to the
equipment. The product nameplate is afxed to the inverter chassis and provides the
following information:
1) Product origin
2) Certication
3) Model type and number
4) DC input ratings
5) AC output ratings
6) Environmental data
7) Protection
8) Adjustable
parameters
UL 1741
CSA-C22.2 No. 107.1-01
C US
®
Country of Origin Italy
www.abb.com/solar
SOLAR UTILITY INTERACTIVE
TRANSFORMERLESS INVERTER
MODEL: UNO-7.6-TL-OUTD-S-US-A
OperatingAmbient Temperature:-25 to +60 °C (-13 to +140 °F), withOutput Power Derating
Type of Enclosure: NEMA 4X
DC Ground Fault Detector/Interrupter is Provided
Photovoltaic Arc-Fault Circuit Protection - Type 1
( ):
1
( ):
2
Adjustable from 57.0 Hz to 59.8 Hz Adjustable from 60.2 Hz to 63.0 Hz
This device complies with Part 15 of the FCC Rules. Operation is subject to the ollowing two
conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesidered operation.
Nominal Input Operating Voltage
Max. Input Voltage
Range of Input Operating Voltage
Range of Input Voltage @Full Power
Max. Input Current
Max. Input ShortCircuitCurrent (P.V. Panels
DC RATING
Nominal Output Voltage
Operating Voltage Range
Nominal Output Frequency
Operating Frequency Range
Output Power Factor
Max. Output Current
AC RATING
Max. Continuous Output Power
Max. Output Overcurrent Protection
2 x 24 A
2 x 30 A
380 V
600 V
90 - 580 V
200 - 480 V
60 Hz (factory preset)
59.3 (
1
) - 60.5 Hz (
2
)
>0.995
27.6 A/ 32 A/36.5 A (rms)
277V~/240V~/208V~ 1Ø
244-304V~/211-264V~/183-228V~
40 A/ 40 A/ 50 A
7600 W @ 50°C amb.
1
2
3
4
5
7
8
6
For more details about product specifications refer to the Instruction Manual

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004CC1
1- Introduction and safety

- 15 -
005CH2
Transportation and handling
When being transported, the inverter and electronic components must be protected from vibration, mechanical
shocks, humidity, etc.
Incoming inspection
It is the customer’s responsibility to examine the condition of the unit. Upon receipt of the inverter check the
following:
• Inspect the shipping container for any external damage.
• Inventory the contents against the table below and verify receipt of all items.
• Use care not to discard any equipment, parts, or manuals.
• Call the delivering carrier if damage or shortage is detected.
If inspection reveals damage to the inverter, contact the supplier or authorized distributor for a repair/return
determination and instructions regarding the process. The equipment components supplied are inserted into a
cardboard box placed within the packaging of the UNO.
QTY Description of carton contents
1
1
1
UNO Inverter
Quick Installation Guide
Equipment components (next page)
2
Installation location

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U006CC2
2 - Installation
Components for all models Description QTY/part#
3 pin connector for congurable
relay
2
82000005907-G
8 pin connector for communication
signals
2
82000005908-G
L-key tool; TORX WRENCH;90° 1
81510000077
Mounting Kit Includes items below XAK.P0101.0
1 Wall bracket for mounting,
6 screws;3x70mm;DIN 7981 A2
and
6 wall anchors,
1 screw; pan head; M6x16;
stainless steel;A2, used for
securing inverter to mounting
bracket
1 (mounting kit)
Jumpers for parallel input mode, 2
ZEC.00074
Optional fused kit Description QTY/part#
The wiring box is designed with
room to accommodate three fused
DC inputs per MPPT channel
resulting in a total of six fused
inputs.
See section 3 for kit installation
instructions.
Included in kit:
12 fuse holders, 1000V, 30A,
12 fuses, 12A
4 bus bars, 3 pin, 1000V, 100A,
4 terminal feeders
XAK.P0103.0

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U006CC2
2 - Installation
Select the installation location
The inverter must be installed by qualied installers and/or licensed electricians ac-
cording to the applicable local code regulations (NEC, CEC, and other).
Once physically mounted, the wiring must be carried out with the equipment discon-
nected from the grid (power disconnect switch open) and the photovoltaic panels
shaded or isolated.
Environmental check
• See technical data in Appendix, part 7, to check the environmental parameters to be
observed (degree of protection, temperature, humidity, altitude, etc.).
• The maximum operational ambient air temperature MUST be considered when choosing
the inverter installation location.
• Installing the inverter where operating temperatures exceed the specications will result
in power limiting.
• Exposure to direct sunlight will increase the operational temperature of the inverter and
may cause output power limiting.
• The use of a sun shade minimizing direct sunlight is recommended when the ambient air
temperature around the unit exceeds 122°F/50°C.
• Do not install in small closed spaces where air cannot circulate freely.
• Due to acoustical noise (about 50dBA at 1 m) from the inverter, do not install in rooms
where people live or where the prolonged presence of people or animals is expected.
• To avoid overheating, always make sure the ow of air around the inverter is not blocked.
• Do not install in places where gases or ammable substances may be present.
Direct sunlight use caution
Air ow restricted use caution

- 18 -
U006CC2
2 - Installation
Installation position
When planning the installation, maintain clearance distances illustrated below to allow normal
control functions and easy maintenance operations. When choosing the location and position,
comply with the following conditions:
• Install on a wall or strong structure capable of bearing the weight.
• Install vertically with a maximum incline of +/- 5°.
• If the mounted inverter is tilted to an angle greater than the maximum noted, heat dissipa-
tion can be inhibited, and may result in less than expected output power.
• Maintain minimum clearances from walls, roofs, ceilings, and other structures as shown
below.
• To avoid overheating, always make sure the ow of air around the inverter is not blocked
by walls, roofs, ceilings, and other objects, including other inverters
• Install in safe place where all switch handles and controls remain easy to reach and meet
height requirements of the applicable electrical code.
• If possible, install at eye level so the display and status LEDs can be easily seen.
• Ensure sufcient working area in front of the inverter to allow removal of the wiring box
cover and easy access for servicing the inverter.
6
in
8
in
2 in 2 in

- 19 -
U006CC2
2 - Installation
When installing multiple inverters side-by-side, mounting handles must be
considered in measurements.
Recommended clearance of 2” between inverters is not required, but a reasonable clearance must be
maintained to allow easy access to handles for mounting/dismounting, and for product and warning
labels to be visible.
UNO
DC Disconnect & Wiring Box
UNO
DC Disconnect & Wiring Box
UNO
DC Disconnect & Wiring Box
UNO
DC Disconnect & Wiring Box
25” handle to handle
23.5” across cover
6”
2”
8”

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U006CC2
2 - Installation