Power One AURORA PVI-STRINGCOMB Quick guide

AURORA
B
OXES FOR THE CONNECTION OF STRINGS FOR
PHOTOVOLTAIC APPLICATIONS
INSTALLATION AND INSTRUCTION MANUAL
Models: PVI-STRINGCOMB / PVI-STRINGCOMB-S
PVI-STRINGCOMB-MC / PVI-STRINGCOMB-S-MC Rev. 1.0


Operation and installation manual Page 2 of 96
(PVI-STRINGCOMB (-S, -MC, -S-MC) - Rev:1.0)
DOCUMENT REVISION TABLE
Document
Revision Author Date Approved by
Change
Description
0.0 A. Morucci
S. Soldani 04-09-09
D.Nocentini
New StringComb
3L11
1.0 A. Morucci
S. Soldani 14-10-09
D.Nocentini
New StringComb
3L11
POWER-ONE: Complete or partial reproduction of this document by any means
whatsoever is strictly forbidden without the authorization of Power-One

Operation and installation manual Page 3 of 96
(PVI-STRINGCOMB (-S, -MC, -S-MC) - Rev:1.0)
CONTENTS
1 GENERAL INSTRUCTIONS ON THE USE AND READING OF THIS
MANUAL ...........................................................................................................................8
1.1 D ISPOSAL OF WASTE .............................................................................................8
1.2 P RODUCT LABELLING ............................................................................................9
1.3 S YMBOLS USED IN THIS M ANUAL .........................................................................9
1.4 S YMBOLS USED ON THE PVI-STRINGCOMB(-S)..............................................11
2 GENERAL INFORMATION AND FEATURES OF A PHOTOVOLTAIC
SYSTEM...........................................................................................................................12
2.1 P HOTOVOLTAIC ENERGY .....................................................................................12
2.2 F UNDAMENTAL ELEMENTS OF A PHOTOVOLTAIC FIELD : “S TRINGS ” AND
“A RRAYS ” ......................................................................................................................13
3 LARGE PHV FIELDS AND PARALLEL STRINGS..........................................15
3.1 W HY USE PVI-STRINGCOMB(-S)?..................................................................15
4 FIELD OF APPLICATION AND GENERAL DESCRIPTION OF THE
PARALLEL STRING PANEL (PSP) ............................................................................18
5 ESSENTIAL INFORMATION FOR SAFETY.....................................................23
5.1 I NTRODUCTION ...................................................................................................23
5.2 O VERVIEW ..........................................................................................................24
6 DESCRIPTIONOFTHEPARTSOFTHEPVI-STRINGCOMB(-S)...........................25
6.1 A SSEMBLY ..........................................................................................................25
6.2 O PERATION DIAGRAM .........................................................................................27
6.3 D ESCRIPTION OF THE SECTIONS ..........................................................................28
6.3.1 Input connections (Ref.§6.1 items A and B, Figure 6-1)............................28
6.3.2 Signal inputs and outputs (Ref.§6.1 item C, Figure 6-1)............................29
6.3.3 Overvoltage protection - DC side ..............................................................29
6.3.4 Overvoltage protection - RS485.................................................................30
6.3.5 DC isolating switch (Ref.§6.1 item G, Figure 6-1) ....................................30
6.3.6 Control unit and serial communication......................................................31
7 CONNECTION OF THE RS485 LINE .................................................................32
7.1 C ONNECTION METHODS ......................................................................................34

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8 TRANSPORT AND STORAGE.............................................................................35
9 INSTALLATION.....................................................................................................36
9.1 P LACE OF INSTALLATION ....................................................................................36
9.2 P OSITIONING .......................................................................................................38
9.3 E LECTRICAL C ONNECTION ..................................................................................40
9.3.1 Removal of the guards................................................................................40
9.3.2 Serial Communication................................................................................41
9.3.3 Analogue inputs..........................................................................................43
9.3.4 PT100 Input................................................................................................44
9.3.5 Antitheft system input / output....................................................................45
9.3.6 Digital inputs..............................................................................................47
9.3.7 Remote disconnection module....................................................................48
9.3.8 +24VDC external power supply.................................................................49
9.3.9 Isolating switch auxiliary status contact....................................................51
9.3.10 Earth connection........................................................................................52
9.3.11 Check on inverter side connections............................................................52
9.3.11.1 Connection of the positive output wire (+) ....................................................52
9.3.11.2 Connection of the negative output wire (-) ....................................................53
9.3.12 Connection of the positive pole of the strings (+) [for max 10 strings].....53
9.3.13 Connection of the Negative poles of the strings (-) [for max 10 strings]...55
9.3.14 Connection of Strings [over 10 strings].....................................................56
9.3.15 Setting the DC switch (only version –S).....................................................56
9.3.16 Connection of the other PVI-STRINGCOMB(-S).......................................57
9.3.17 Closing the DC switch (only version –S)....................................................57
9.3.18 Final checks ...............................................................................................57
9.3.19 Closing the cover .......................................................................................57
9.3.20 Assigning the FIELD NUMBER.................................................................57
10 DISCONNECTION AND MAINTENANCE ....................................................58
10.1 D ISCONNECTION OF THE PVI-STRINGCOMB(-S).............................................58
10.1.1 Complete disconnection.............................................................................59
10.1.2 Disconnecting the strings...........................................................................60
10.2 M AINTENANCE ( REPLACEMENT OF FUSES / DISCHARGERS ).................................61
10.2.1 Replacing the dischargers..........................................................................61
10.2.2 Replacing the fuses.....................................................................................61
11 BEFORE USING THE SOFTWARE ................................................................62
11.1 I NSTALLATION OF SOFTWARE .............................................................................62

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12 MONITORING AND CONFIGURATION INTERFACE ..............................63
12.1 C ONVENTIONS USED ...........................................................................................63
12.2 A CCESS LEVELS ..................................................................................................63
12.3 F IRST INSTALLATION ..........................................................................................64
12.4 A SSIGNING THE F IELD N UMBER ..........................................................................67
12.4.1 What is the Field Number? ........................................................................67
12.4.2 Operations for assigning the Field Number...............................................69
12.5 PVI-STRINGCOMB M ANAGER ........................................................................71
12.5.1 S.Comb Baud-Rate Setting.........................................................................72
12.6 PVI-STRINGCOMB M ONITORING (G LOBAL )...................................................73
12.7 PVI-STRINGCOMB M ONITORING (S INGLE ).....................................................74
12.8 D ETAIL OF C ONFIGURATION SUB - MENU .............................................................78
12.8.1 Configuration  Alarm Parameters..........................................................78
12.8.2 Configuration  String Current Settings ..................................................79
12.8.3 Configuration  Aux Inputs Settings ........................................................82
12.8.4 Configuration  Digital Inputs Settings ...................................................84
12.9 MONITORING EXAMPLES............................................................................87
13 TROUBLESHOOTING ......................................................................................90
13.1 B EFORE CONTACTING THE TECHNICIAN (Q UESTIONNAIRE ).................................92
14 APPENDIXES......................................................................................................93
14.1 A PPENDIX A: T ECHNICAL D ATA .........................................................................93
14.2 A PPENDIX B: D ECLARATION OF C ONFORMITY ...................................................95

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INDEX OF FIGURES:
F IGURE 1-1: P RODUCT LABEL ( EXAMPLE ).............................................................................9
F IGURE 1-2: P OWER INPUTS AND OUTPUTS LABEL ................................................................9
F IGURE 2-1: A RRAY COMPOSITION .....................................................................................13
F IGURE 3-1: E FFECT OF A PANEL BREAKDOWN WITH SHORT - CIRCUIT .................................16
F IGURE 3-2: I NTERVENTION OF PROTECTIVE FUSE ..............................................................17
F IGURE 4-1: PVI-STRINGCOMB(-S)................................................................................18
F IGURE 4-2: E XAMPLE OF A PHOTOVOLTAIC SYSTEM .........................................................21
F IGURE 4-3: A VAILABLE I NPUTS /O UTPUTS + ACCESSORIES ................................................22
F IGURE 6-1: I NSIDE OF THE PVI-STRINGCOMB-S...........................................................25
F IGURE 6-2: I NSIDE THE PVI-STRINGCOMB-S................................................................26
F IGURE 6-3: I NDICATIVE ELECTRICAL DIAGRAM OF THE PVI-STRINGCOMB(-S)............27
F IGURE 6-4: T ERMINAL BOARDS FOR POSITIVE STRINGS INPUT (A) AND NEGATIVE STRINGS
INPUT (B) + STRING FUSE CARRIER ..............................................................................28
F IGURE 6-5: T ERMINAL BOARD FOR THE CONNECTION OF THE ANALOGUE INPUTS .............29
F IGURE 6-6: DC ISOLATING SWITCH (1), COMPONENT FOR REMOTE DISCONNECTION AND
AUXILIARY STATUS CONTACT (2)................................................................................30
F IGURE 6-7: D ETAIL OF THE M ICRO - CONTROLLER AND RS485 S ERIAL Z ONE ....................31
F IGURE 7-1: M ODALITY FOR THE PASSAGE OF THE SERIAL WIRE ........................................32
F IGURE 7-2: T YPE OF CONNECTION FOR THE PVI-STRINGCOMB(-S)..............................33
F IGURE 7-3: C ONNECTION METHODS ..................................................................................34
F IGURE 9-1: E XAMPLE OF BOX POSITION ............................................................................37
F IGURE 9-2: P OSITIONING OF THE BOX AND AN EXAMPLE OF WIRE SUPPORT ......................38
F IGURE 9-3: C OMPLETE USE OF THE PVI-STRINGCOMB(-S) (20 STRINGS ) .....................39
F IGURE 9-4: R EMOVAL OF THE P LEXIGLAS GUARDS ...........................................................40
F IGURE 9-5: RS485 LINE TERMINAL BOARD .......................................................................41
F IGURE 9-6: G ROUND TERMINAL FOR RS485 LINE SHIELDING ............................................42
F IGURE 9-7: M ICRO - SWITCH FOR RS485 LINE TERMINATION .............................................42
F IGURE 9-8 : T ERMINALS FOR ANALOGUE INPUTS CONNECTION .........................................43
F IGURE 9-9: T ERMINALS FOR PT100 SENSOR CONNECTION ................................................44
F IGURE 9-10: E XAMPLE OF ANTITHEFT SYSTEM CONNECTION ............................................45
F IGURE 9-11: T ERMINALS FOR ANTITHEFT SYSTEM ALARM CONNECTION ...........................46
F IGURE 9-12: T ERMINALS FOR DIGITAL INPUTS CONNECTION .............................................47
F IGURE 9-13 : T ERMINALS FOR REMOTE DISCONNECTION MODULE CONNECTION ...............48
F IGURE 9-14: T ERMINALS FOR EXTERNAL +24VDC SUPPLY CONNECTION .........................49
F IGURE 9-15: E XTERNAL +24VDC SUPPLY SWITCH ...........................................................50
F IGURE 9-16: I SOLATING SWITCH STATUS CONNECTOR ......................................................51
F IGURE 9-17: C ABLE GLAND FOR GROUND CONNECTION ....................................................52
F IGURE 9-18: C ABLE GLAND FOR POSITIVE STRINGS CONNECTION .....................................53

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F IGURE 9-19: U SE THE SPECIAL SCREWDRIVER ON THE TERMINALS ...................................54
F IGURE 9-20: C ABLE GLAND FOR NEGATIVE STRINGS CONNECTION ...................................55
F IGURE 9-21: LED INDICATING NORMAL OPERATION .........................................................56
F IGURE 12-1: E XAMPLE OF A COMPLETE SYSTEM MAP .......................................................68
F IGURE 12-2: G LOBAL M ONITORING P ANEL .......................................................................73
F IGURE 12-3: S INGLE M ONITORING P ANEL ........................................................................74
F IGURE 12-4: PVI-STRINGCOMB(-S) S TATUS P ANEL .....................................................75
F IGURE 12-5: C URRENT / WEIGHT READING PANEL .............................................................76
F IGURE 12-6: S2 SWITCH TO ENABLE PT100.......................................................................83
F IGURE 12-7: A UXILIARY INPUTS MONITORING (IN2 G ENERIC , IN2 PT100)......................84
F IGURE 12-8: S4 SWITCH TO ENABLE ISOLATING SWITCH STATUS CHECK ...........................85
F IGURE 12-9: D IGITAL INPUTS MONITORING (ID1 G ENERIC , ID1 DC SWITCH )....................86
INDEX OF TABLES:
T ABLE 9-1: T ABLE OF RS485 CONNECTION ........................................................................41
T ABLE 9-2: T ABLE OF ANALOGUE INPUTS CONNECTION .....................................................43
T ABLE 9-3: T ABLE OF PT100 CONNECTION ........................................................................44
T ABLE 9-4: T ABLE OF ANTITHEFT SYSTEM ALARM CONNECTION ........................................46
T ABLE 9-5: T ABLE OF DIGITAL INPUTS CONNECTION ..........................................................48
T ABLE 9-6: T ABLE OF REMOTE DISCONNECTION MODULE CONNECTION .............................48
T ABLE 9-7: T ABLE OF EXTERNAL +24VDC SUPPLY CONNECTION ......................................49
T ABLE 9-8: T ABLE OF ISOLATING SWITCH AUXILIARY CONTACT CONNECTION ...................51
T ABLE 13-1: T ROUBLESHOOTING .......................................................................................90
T ABLE 14-1: T ECHNICAL D ATA ..........................................................................................93

Operation and installation manual Page 8 of 96
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1 GENERAL INSTRUCTIONS ON THE USE AND READING OF
THIS MANUAL
This documentation is valid for all PVI-STRINGCOMB(-S) products.
The product to which this Manual refers must be used only for the purpose
described in Chapter §4. Any other use is inappropriate and therefore
dangerous. Power-One declines all responsibility for damages to property or
persons due to use which is inappropriate and/or other than that foreseen.
Before replacing the components in the device and mentioned in this Manual,
particularly the dischargers and the fuses, the supplier must be contacted:
Power-One shall accept no responsibility for damages consequent to the use
of unsuitable spare parts.
Power-One reserves the right to make any amendments to this Manual and to
the device without advance notice: the most recent version of the Manual,
indicating the revision number, is available at the site (www.power-one.com).
This Manual contains important instructions regarding safety and functioning,
which must be understood and carefully followed during installation and
maintenance of the device.
1.1 Disposal of waste
As a manufacturer of the electrical device described in this manual,
and in compliance with Decree Law 25/07/05 no.151, Power-One
informs the buyer that when this product is scrapped it must be
delivered to an authorised disposal centre
.

Operation and installation manual Page 9 of 96
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1.2 Product labelling
Figure 1-1: Product label (example)
The identification label affixed to the PVI-STRINGCOMB(-S) contains the
following information:
1) Power-One product's production code
2) Model name
3) Serial number
4) Week/Year of production
5) Serial address RS485
6) Product revision
Figure 1-2 shows the label specifying input and output polarities.
Figure 1-2: Power inputs and outputs label
1.3 Symbols used in this Manual
1
2
3
5
6
4

Operation and installation manual Page 10 of 96
(PVI-STRINGCOMB (-S, -MC, -S-MC) - Rev:1.0)
To reduce the risk of electric shock, and to ensure that the device is correctly
installed and ready for use, special safety symbols are used in the Manual to
indicate potential risks or useful information. The symbols are:
ATTENTION
Paragraphs marked by this symbol contain actions and/or instructions
which it is essential to understand and to carry out in order to avoid
potential malfunctioning of the device or damage to the same and to
property in general.
DANGER!
Paragraphs marked by this symbol contain specific indications which
must absolutely be followed in order to avoid accidents or even death
by electrocution.
IMPORTANT
Paragraphs marked by this symbol contain important information
regarding use of the device.
PROTECTION!
Paragraphs marked by this symbol indicate the need for adequate
protection before carrying out operations (e.g. insulating gloves for
operating with voltages up to 1000Vdc, protective goggles, etc.).

Operation and installation manual Page 11 of 96
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1.4 Symbols used on the PVI-STRINGCOMB(-S)
The device has various labels; those with a yellow background regard the safety
devices provided.
Make sure that you have read and fully understand the labels before installing the
device.
The symbols used on the device, referring to electrical parts, are the following and
they are also used in this Manual:
Connection point for the earth conductor
+
Continuous positive voltage pole
-
Continuous negative voltage pole
Direct Current (DC)
Grounding (GND)

Operation and installation manual Page 12 of 96
(PVI-STRINGCOMB (-S, -MC, -S-MC) - Rev:1.0)
2 GENERAL INFORMATION AND FEATURES OF A
PHOTOVOLTAIC SYSTEM
This chapter gives the PVI-STRINGCOMB(-S) user general information on
photovoltaic plants which transform solar energy into electricity, which can be
used in the mains network.
2.1 Photovoltaic energy
In the energy transformation process, industrialised companies (the greatest
energy consumers) have been experimenting methods for energy saving and for
decreasing the release of polluting substances into the environment for many
years, by careful and rational consumption of known resources and by research
into new forms of clean and inexhaustible energy.
Regenerating sources of energy are fundamental to solve this problem. Under
these circumstances, solar energy exploitation to generate electrical
(photovoltaic) energy is becoming more and more important world-wide.
Photovoltaic energy represents an enormous advantage as regards
environmental protection, since the solar radiation which we receive from the sun
is directly transformed into electricity without any combustion process and without
the production of polluting waste.
The photovoltaic panels transform the energy irradiated by the sun into direct
current, or DC type electricity (by means of a photovoltaic field, also known as a
PV generator). In order to supply the mains network and thus allow for this energy
to be used, it must be transformed into alternate current, or AC type electricity.
AURORA inverters do this conversion, also known as DC to AC inversion, in a
very efficient way, without using rotating parts but just static power electronic
devices.
Used parallel to the mains supply, the alternate current produced by the inverter
flows directly (through the insulation transformer) into the industrial distribution
network, in turn connected to the public distribution network.
When the photovoltaic field is not generating sufficient energy, the power required
to ensure proper operation of connected loads is taken from the public power grid.
While if the produced energy is too much, it is directly fed to the grid, thus
becoming available to other users.

Operation and installation manual Page 13 of 96
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According to national and local standards and regulations the produced energy
can be sold to the grid or credited to the user against future consumption, thus
granting a great saving of money.
2.2 Fundamental elements of a photovoltaic field: “Strings” and
“Arrays”
The so-called STRINGS technology has been developed in order to reduce the
installation costs of a photovoltaic system as much as possible. These costs are
mainly related to the wiring operations on inverter DC side and the consequent
distribution on the AC side.
A photovoltaic panel is composed of many photovoltaic cells assembled on the
same mount. A STRING is composed of a certain number of panels electrically
connected in series. An ARRAY is composed by one or more strings connected in
parallel.
Photovoltaic systems of a certain size may be composed of several arrays,
connected to one or more AURORA inverters.
The greater the number of panels in each string, the lower the cost and the less
complex the wiring connections of the system.
PV Panel
PV String
PV Array
PV Cell
+
+
_
_
+
_
Figure 2-1: Array composition

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WARNING: In no case may the voltage of the string exceed the
maximum voltage admissible, otherwise the device will be damaged
(see APPENDIXES).
The current of each array must also be within the limits of the inverter
downstream.
There are several factors and considerations to be taken into account when
designing a photovoltaic system, such as the type of panels, available room,
location, long-term target output, etc. The system configurator available on
Power-One's web site (www.power-one.com) may help in sizing a photovoltaic
system.

Operation and installation manual Page 15 of 96
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3 LARGE PHV FIELDS AND PARALLEL STRINGS.
When speaking of large photovoltaic fields, the immediate image is one of large
extensions of solar panels.
Since a field (array) is composed of several parallel strings, it is clear that to
obtain high power the number must be increased. In this case, particular
precautions must be taken in the project / installation phase, otherwise the strings
may be damaged due to breakdowns in the strings themselves or to incorrect
connections or dimensioning.
3.1 Why use PVI-STRINGCOMB(-S)?
Connecting strings in parallel does not entail particular problems as long as the
"Uoc" voltage (Open Circuit Voltage) for each string is the same as the other
strings. If not, e.g. because of considerable differences in the length of the strings
or short circuits in one or more of the solar modules in a string, there can be a
considerable difference in the Uoc voltage which can cause an inverted current
on the string with the lower voltage (i.e. made up of a lower number of modules
connected in series). Contrary to popular opinion, shading has no significant
influence on this effect; this is because Bypass diodes have been adopted and
they are now standard on all panels.
If the inverted current is greater than the maximum permitted for the panel, it can
overheat and/or even be irreparably damaged (Figure 3-1).
Diodes can be inserted in series to each string (string blocking diodes) to
prevent this problem. Using these diodes has two disadvantages: 1) The
string current pass through the diode and consequently the loss of power
is not negligible. 2) If there is a short circuit in the diode, there is no
protection and the phenomenon in Figure 3-1 can occur.
The best solution is to use a fuse for every string.
In the event of excessive inverted current, the fuse opens and protects
the string itself (Figure 3-2). If the fuse status is monitored, it is also now
possible to remotely check the status of the strings which make up the
photovoltaic generator. Moreover, a fuse's power losses are considerably
less than a diode's. The PVI-STRINGCOMB has fuses both on the
positive pole and on the negative pole of each string.

Operation and installation manual Page 16 of 96
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The fuse rating must be chosen by taking into consideration the maximum
current that can flow through the fuse (also based on the number of
strings connected to the channel in the parallel string panel) and the
maximum inverted current that each string can take. The technical data
sheets of the photovoltaic modules generally show the "Max Fuse
Rating", i.e. the maximum fuse rating that can be adopted to protect the
panel string. Usually the "Max Fuse Rating" is double of the module's
short circuit current. This allow two strings to be connected directly in
parallel without running the risk of damage to the panels. Nevertheless
these are considerations of a general nature which must be verified by a
careful check on the characteristics of the modules that make up the
photovoltaic generator.
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
Uoc1
+
-
+
-
+
-
+
-
Uoc2
+
-
+
-
+
-
+
-
Uoc3
Uoc2 < (Uoc1 = Uoc3)
INVERTER
Figure 3-1: Effect of a panel breakdown with short-circuit

Operation and installation manual Page 17 of 96
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Figure 3-2: Intervention of protective fuse
With PVI-STRINGCOMB(-S), the connected strings are protected and
controlled. In addition, information on the string currents, and other
information, can be recorded, which can be useful during system
operation.

Operation and installation manual Page 18 of 96
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4 FIELD OF APPLICATION AND GENERAL DESCRIPTION OF
THE PARALLEL STRING PANEL (PSP)
Figure 4-1: PVI-STRINGCOMB(-S)
The PVI-STRINGCOMB(-S) and its variants (Figure 4-1) are devices designed
exclusively for parallel connection of the photovoltaic field strings, allowing for
protection in the case of breakdown.
Besides connecting the strings, they allow the electrical quantities and other type
of quantities for the entire photovoltaic field to be monitored through the following
checks:
−Reading the total voltage of the field.
−Checking the operation of the internal fuses, to protect the photovoltaic
panels.
−Checking of the status of the internal protection against overvoltage (DC
side).
−Temperature check.
−General checks on the surrounding environment through external sensors.

Operation and installation manual Page 19 of 96
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Thanks to the 10 channels available, each device allows for connecting up to 10
strings individually, or 20 strings in parallel pairs. This is made possible thanks to
the double-hole terminal board on each channel (from 1 to 10). Each channel is
also protected by two fuses.
The "S" version has:
•a special DC switch for direct current disconnection with high voltages
(1000Vdc) in class DC21A; this allows for disconnecting the string group
concerned from the inverter downstream.
•remote disconnection control and an auxiliary contact for displaying the
switch status.
Every device features:
•one input for resistance PT100
•analogue and digital inputs to allow for checking external magnitudes
1
,
such as, for example, the temperature of the photovoltaic cells, solar
irradiation, environmental temperature, wind force, etc.
•a cord-type antitheft device.
•a protection against overvoltage for the serial line RS485 (supplied as an
option).
•a protection against overvoltage for the DC line.
1
The 24V sensors for measuring environment parameters can be fed by a source
external to or the one internal to the PVI-STRINGCOMB(-S) (Ref.§9.3.3, §9.3.8)

Operation and installation manual Page 20 of 96
(PVI-STRINGCOMB (-S, -MC, -S-MC) - Rev:1.0)
Every device can be powered by an external source (24V DC). This allows the
PVI-STRINGCOMB(-S) to remain running also during the night.
PSPs are available in four different versions. The differences are the
presence or not of the switch disconnector and the string connection type.
PSPs should be configured when placing the order using the
configuration model that can be found on the internet at the following
address: www.stringcombconfigurator.com
String-combs can be configured in different ways according to:
•Number of strings that can be connected
•Cable gland type or MC4 string input connector type
•Size of fuses
•Parallel string output cable gland
•Cable gland for the ground cable
More information are available on the website.
Figure 4-2 shows an example of the connection, by means of PVI-
STRINGCOMB(-S), of a 100kw centralised AURORA inverter to a photovoltaic
field composed of 2 arrays (photovoltaic field A and B), each in turn consiting of 4
strings.