FuturaSun Silk Plus Duetto Series Setup guide

Safety and installation
manual
Photovoltaic modules: Silk®Plus Duetto
and Silk®Premium Max Duetto series
futurasun.com

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This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
CONTENTS
1. General Information 3
2. Disclaimer of Liability 4
3. IEC 61215 & 61730 certifications 4
4. Limited Warranty 4
5. Module Specification 4
6. Safety Precautions 4
7. Installation 6
8. Use and Maintenance 11
9. Packaging, Handling and Storage of Modules 12
The specifications in this manual are subject to revisions without further notice

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FuturaSun srl –The specifications in this manual are subject to revisions without further notice
This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
1. General Information
The photovoltaic (PV) modules Silk®Plus
Duetto / Silk®Premium Max series, (hereafter
“FU XXX”or “FU”) are devices that produce
electrical energy by converting the sunlight’s
radiation reaching their surface, when
appropriately exposed, into continuous/direct
current (DC).
The FU modules are intended to be used in
photovoltaic module systems connected to the
electrical grid. It is also possible to use them in
battery powered photovoltaic module systems
(stand alone).
The rated currents at Standard Test
Conditions (STC) of the FU modules are
variable depending on the model and the
relative power rating, as indicated in the
respective technical data sheets. Most of the
electrical parameters of the modules, specified
in the datasheets, are determinable only by
using special instrumentation in the laboratory;
therefore, only some of them are measurable
outside of a lab, using common
instrumentation (voltmeter, AM meter,
solarimeter/pyranometer).
It is possible, following very precise
procedures, to carry out electrical
measurements of voltage and current as
snapshots, which enable you to monitor the
operation of the modules and determine
possible, although rare, anomalies.
The electrical output parameters for FU
modules, of technical importance during the
operation, installation and maintenance, are
the following:
•Voltage at open circuit (Voc) with
tolerance of ± 4%
•Current at short circuit (Isc) with
tolerance of ± 5%
•Voltage at point of maximum power
(Vmpp)
•Current at point of maximum power
(Impp)
•Power (Pmax) with tolerance of ± 3%
•Solar radiation in W/m2at the time
•Temperature of the modules
The general performance of the modules is
heavily dependent on the intensity of the
incident solar radiation, as illustrated in Fig.1.
Acheiving maximum performance requires
proper installation, with the modules oriented
towards the South in northern hemisphere and
their surface exposed as perpendicularly as
possible to the incident rays of the sun;
furthermore, avoiding any shading caused by
obstacles in and around the area of
installation.
Fig. 1: IV curve at different irradiance
A high ambient temperature and therefore, an
increased operational temperature of the
modules, also contribute to a proportional
reduction in electrical performance. Please
see fig. 2
Fig. 2: IV curve at different temperatures

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In order to optimize the production of electrical
energy of the modules, and therefore of the
system connected to an electrical grid, it is the
responsibility of the installer to make sure the
modules are positioned as much as possible
facing south in northern hemisphere, with the
tilt angle (β) (inclination of the surface of the
modules in respect to the ground, as shown in
Fig.3) optimal for the type of desired
application.
The tilt angle of ideal average throughout Italy
is β= 30°;however, even the inclination typical
the roof of a dwelling (β = 15-20°), being
already an inclined plane, could make the
angle acceptable, if not ideal, for the
installation of coplanar modules on it (using a
special standard structure for support).
Depending on the variation of the tilt angle of
the modules with respect to the ground, or of
their orientation in relation to facing south
(Azimuth), there will be changes in the annual
average amount of energy produced by the
modules themselves, and therefore, of the
plant connected to the network to which they
are linked.
Fig. 3: Orientation Vs. Azimuth
2. Disclaimer of Liability
Since the methods of system design,
installation techniques, handling and use of
this product are beyond company control;
FuturaSun does not assumeresponsibility and
expressly disclaims liability, for loss, damage
or expense resulting from improper
installation, handling or use.
3. IEC 61215 & 61730 certifications
This product meets or exceeds the
requirements set forth by IEC 61215:2016 and
61730:2016 for PV Modules. These standards
cover flat-plate PV modules and panels
intended for installation on buildings or those
intended to be freestanding. This product is
not intended for use where artificially
concentrated sunlight is applied to the module.
4. Limited Warranty
Please refer to FuturaSun General Sales
Conditions and Product and Performance
Warranty for details of the modules’ limited
warranty. Failure to comply with this Safety
and Installation Manual will invalidate
FuturaSun Warranty for the PV modules as
stated in the Product and Performance
Warranty.
5. Module Specification
Please refer to the technical datasheet for the
module FuturaSun FU XXX respectively for
electrical performance data. These electrical
data are measured under Standard Test
Conditions (STC) of 1000 W/m2irradiance,
with Air Mass (AM) of 1.5 spectrum, and a cell
temperature of 25°C. The energy output of
bifacial module can be affected by albedo of
the ground that module installed on, height of
module, Ground coverage Ratio (GCR), and
Diffused horizontal irradiance.
6. Safety Precautions
Installation should be performed only by
authorized personnel!
•Module installation must be performed in
compliance with the latest IEC code (CEI
in Italy).
•Within the modules, there are no user
serviceable parts. Do not attempt to repair
any part of the modules. Contact your
module supplier if maintenance is
necessary.
•In order to reduce the risk of electric shock,
prior to installing the modules, remove
metallic jewelry and use insulated tools
during installation.
•Do not expose the modules to artificially
concentrated sunlight!
•Do not stand on, drop, scratch, or allow
objects to fall on the modules.
East

South

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•Do not lift themodules at the connectors or
junction box!
•Do not install or handle the modules when
they are wet or during periods of high
winds.
•Do not use oil-based lubricants on any part
of the junction box as this can cause long-
term damage to the plastics.
•Ensure that wire cable connections are
routed in accordance with the junction box
manufacturer’s recommendations.
Incorrect routing of the wire cable can lead
to stress damage to the junction box.
•The minimum cable diameter for the
modules intended for field wiring is 4 mm².
•Please use the connectors following your
national regulation: i.e. in some countries
it is required to use always the same
connector in the entire system Please
contact Futurasun to know the exact
connector type used in the module you
have purchased.
•FuturaSun Duetto series use various
connector suppliers, please ensure with
your local FuturaSun representative the
correct voltage rating of the connectors for
your system.
•The rated voltage for the connectors must
be 1500V for 1500V systems and the rated
current ≥ 30 A.
•The cross section for the connector is 1 x
4,0 mm².
•Do not leave cable connectors exposed in
adverse climatic conditions. Water and
dust deposits inside the cable connectors
can cause long-term damage.
•Broken module glass, a torn back sheet,
a broken junction box or broken
connectors are electrical safety hazards;
consequently, contact with a damaged
module can cause electric shock.
•Fire ratings: Spread of Flame and Burning
brand Fire Class C (acc. to UL
61730/UL790). Ignitability Test Class E
(acc. to IEC 61730-2).
•The total voltage of modules connected in
series corresponds to the sum of the
voltages of the single modules; whereas
connecting the modules in parallel results
in adding up the currents. Consequently,
strings of inter-connected modules can
produce high voltages and high currents
and constitute an increased risk of electric
shock and may cause injury or death.
•Modules shall not be connected in series
to create strings with a higher voltage than
the maximum system design voltage
and/or the maximum range allowed by the
inverter and/or the safe operational
voltage range of safety devices
/switchgears composing the system, in the
environmental conditions the system will
be installed.
•For installation, maintenance, or before
making any electrical connection or
disconnection, ensure all modules in the
PV array are exposedto a light intensity
that is less than 400 W/m2!! If necessary,
the modules should be covered with an
opaque cloth or other material in order to
shield them from exposure to light intensity
greater than 400 W/m2.
6a) Fire Risks
•Solar panels are designed and
manufactured to meet stringent safety
standards and minimize fire risks.
However, risks can be further reduced
through good periodic cleaning of the
panels (see section 8d) and regular
inspection of the system with an
infrared camera and/or a portable
electroluminescence device. Especially
after events such as heavy hail storms,
or other extreme environmental
phenomena. On the other hand, it is
important to recognize that improper
installation, maintenance or use can
instead increase the risk of fire. To reduce
the risk, the following guidelines should be
followed:
1. Ensure proper installation by professional
installer in accordancewith local electrical
codes and installation manual, improper
installation mayresult in electrical faults or
damage to the system.
2. Regular maintenance this include
checking loose connections, damaged
cables or signs of degradation and any
abnormalities should be promptly
addressed to prevent fire hazards.
3. Temperature monitoring to detect any
abnormal heat generation, as excessive
heat can lead to electrical malfunction.
Monitoring equipment used shall be
regularly maintained calibrated.
4. Ensure that the system has electrical
protection in terms of circuit breakers,
fuses and surge protection devices.

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This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
5. Maintain clear access for maintenance
and emergency purposes and clear away
any obstructions or debris such as
overgrown vegetation.
6. Use proper wiring and conduit.
7. Provide specific training per protocol used
in response to fire of PV system including
shut down the system in an emergency
and report any abnormalities.
7. Installation
Climate conditions:
1. Ambient Temperature: -40°C to +40°C
(-40°F to +104°F)
2. Operating Temperature: -40°C to 85°C
(-40°F to +185°F) IEC Standard.
3. Operating Temperature: -40°C to
+90°C (-40°F to 194°F) UL61730
standards.
4. Humidity: ≤ 85% RH
7a) Module Mounting
•The FU modules are qualified for an
operative temperature within the range of -
40 to +85 °C.
•The FU modules can be installed at a
maximum operating altitude of ≤ 2000
meters.
•When installing FU modules, local building
code requirements and regulations must
be observed at all times. Sufficient
ventilation of the module backside is
required and the mounting configuration
(e.g. sufficient clearance) should be
adapted accordingly.
•Do not drill any additional holes into the
module frames and do not cover the
drainage holes.
•Pre-assembled mounting systems
must be confirmed by FuturaSun in
writing in advance.
•The modules can be mounted in every
angle from horizontal to vertical, avoiding
configurations with the junction box up-
side down at all times (e.g. trackers with
“sleep mode”).
•In order to maximize module exposure to
direct sunlight, the modules should be
oriented to the south in the northern
hemisphere and to the north in the
southern hemisphere.
•Installation height of bifacial module is
recommended to be higher than 1 meter in
order to harvest maximum available
reflected and diffused radiation and to
reduce shading on the backside.
•Structure, cables and any other
component of installation should not cause
shading on the backside of the modules.
•⚠CAUTION, do not walk over the
modules, right walkways should be
considered in the installation for
cleaning, repair and maintenance.
•⚠CAUTION, low-angle installations do
not allow proper water runoff by
allowing water, dust and/or other
subjects to persist on the surface, these
factors over time can affect performance
and proper module operativity. It is
strongly discouraged to install modules
with an inclination of less than 5°.
Mounting Methods:
Mounting using mounting holes:
•Each module must be securely fastened at
a minimum of 4 points.
•Use the mounting holes (slots, see Fig.
5,6,7,8) on the PV module frame to bolt the
module withstainless steel screwsand nuts
to the mounting framework. The
recommended torque is at least 17-23 Nm.
•The distance of the mounting holes has
been designed in order to result in a
uniform wind and snow load without
damaging the module
•The distance of the mounting holes can
be modified without further notice, if you
use this type of mounting, it is
recommended to always ask the
manufacturer for confirmation.
•Do not drill additional holes in the module
frame; doing so will void the warranty.
Mounting using clamping method:
•FuturaSun recommends the use of clamps.
•Each module must be securely fastened
with minimum of 4 clamps
•⚠Only long sides are useful for
clamping
•⚠Use clamps suitable for the module
thickness and with a minimum length of
80 mm
•When using clamps, it is possible to mount
the modules in horizontal (the shorter side
of one module facing the shorter side of the
neighboring module) or in vertical (the

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longer sides facing each other)
configuration always observing the areas
allowed for fixing. It is recommended to
always use stainless steel screws and
bolts. The recommended torque is 17-23
Nm.
•The modules can be mounted on
continuous base structures (inclined or
horizontal) such as rails or similar.
•Both base structures must be mounted at
the same distance from the symmetrical
axis (vertical or horizontal) of the module.
•In vertical configuration, it is strongly
recommended to place the supporting
elements nearby the mounting holes, or in
any case, the distances shown in Fig. 4
should be respected. This is necessary in
order to maintain a correct load distribution.
•The FU XXX modules are qualified to 3600
Pascal (5400 including a safety factor of
1.5) on the front side and 1600 Pascal
(2400 including a safety factor of 1.5) when
the module is fixed in the green area (See
Fig. 4)
•In accordance with Eurocodes - EN 1991,
in the 3,4,5 area of the Alpine Region, if
fixing are in the yellow and violet areas
(See Fig. 4) the load capacity of module
could be too low compared to what is
necessary. The shape coefficient, the
modules tilt and the installation layout must
be taken into account. An accurate check
must always be carried out by qualified
technician.
•In horizontal configuration, fixing the
modules by clamping in the green area in
fig. 4 is certified to retain the characteristics
regarding the static loads.
•When clamping the modules in horizontal
configuration on a support structure, the
distances in Fig. 4 have to be applied in
order to maintain the resistance against
static loads as certified.
•The modules can also be fixed by placing
them with their frame on a structure that is
supporting the two sides of the frame over
their whole length. Also in this case, the
position of the mounting clamps must be in
accordance with distances indicated in Fig.
4.
•At least 20 mm spacing must be maintain
on all sides between modules.
Fig. 4: Positions for clamping and fixing
FUXXXMV Silk®Plus Duetto / Silk®Premium Max
Duetto
Legend:
•The green areas allow for a certified design
load of 3600 Pa.
•The yellow areas allow for a maximum load
between 2400 to 1600 Pa.
•The purple areas allow for maximum load
lower than 1600 Pa.
•The red areas are not allowed for clamping
an fixing.
⚠CLAMPING ON SHORT SIDES IS NOT
ALLOWED

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Fig. 5: Mechanical drawing of the FUXXX MV Silk®
Plus Duetto (108 half-cut cells) module showing the
mounting holes.
Note: dimensions in mm
Tolerance -/+ 2mm
Table 1: Distances for FU XXX MV Silk®Plus
Duetto (108 half-cut cells) from edge for clamping
and fixing (mm)
FU XXX MV Silk ®Plus Duetto (120 half-cut cells)
Color
min
max
Green
400
500
Yellow (2400Pa)
500
550
Yellow (2000Pa)
0
400
Purple
550
600
Red
600
1122
Tolerance ± 2 mm
Fig. 6: Mechanical drawing of the FU XXX MV
Silk® Plus Duetto (144 half-cut cells) module
showing the mounting holes.
Note: dimensions in mm
Tolerance -/+ 2mm
Table 2: Distances for FU XXX MV Silk®Plus
Duetto (144 cells) from edge for clamping and
fixing (mm)
FU XXX MV Silk®Plus Duetto (144 half-cut cells)
Color
min
max
Green
400
500
Yellow (2400Pa)
500
600
Yellow (2000Pa)
0
400
Purple
600
700
Red
700
1556
Tolerance ± 2 mm

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Fig. 7: Mechanical drawing of the FU XXX MV
Silk® Premium Max Duetto (120 half-cut cells)
module showing the mounting holes.
Note: dimensions in mm
Tolerance -/+ 2mm
Table 3: Distances for FU XXX MV Silk®Premium
Max (120 cells) from edge for clamping and fixing
(mm)
FU XXX MV Silk®Premium Max Duetto
(120 half-cut cells)
Color
min
max
Green
400
500
Yellow (2400Pa)
500
600
Yellow (2000Pa)
0
400
Purple
600
700
Red
700
1472
Tolerance ± 2 mm
Fig. 8: Mechanical drawing of the FU XXX MV
Silk®Premium Max Duetto (132 half-cut cells)
module showing the mounting holes.
Note: dimensions in mm
Tolerance -/+ 2mm
Table 4: Distances for FU XXX MV Silk®Premium
Max (132 cells) from edge for clamping and fixing
(mm)
FU XXX MV Silk®Premium Max Duetto
(132 half-cut cells)
Color
min
max
Green
400
500
Yellow (2400Pa)
500
600
Yellow (2000Pa)
0
400
Purple
600
700
Red
700
1684
Tolerance ± 2 mm

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7b) Module Handling
The FU modules are robust, but in particular,
the glass front cover may be subject to
damage if improperly handled or installed.
Wear protective gloves when handling and
installing the modules in order to be protected
against cutting by sharp edges and against
skin burns. Handle the module in a way that
avoids breakage or scratching of the front
cover glass and mechanical damage to any
other part of the module. Do not carry the
module by its connector wires in order to avoid
the risk of electric shock and prevent damage
to the module.
During the wiring and installation of the
modules use caution! Do not trample on or
scratch the modules. Do not drop sharp or
heavy objects on either surfaces of the
module. Do not subject the modules to any
impact, in particular in the vicinity of the edges
of the frames and do not flex them
mechanically. The modules are made of a
single laminate,thereforeonce damaged, they
are not repairable.
In the event of any damage to either the front
or the back of the module, the part exposed
might be electrically active and therefore
dangerous, especially if the module is
connected in series to a string.
7c) Electrical ConnectionDanger!
Risk of serious injury or death from electric shock
or electric arc flash! Do not connect or disconnect
modules under load!
Even if the modules are protected against
accidental contact, under unfavorable
conditions high hazardous voltage (several
hundreds of volts) may occur during
installation. Consequently, installation and
maintenance of the modules, as well as the
connection to the main power supply, may
only be performed by authorized and qualified
persons. Before connection of the system to
the grid, the PV system must be approved for
correct installation, by an electrician
responsible to the operator and the local
electricity company.
The design of the PV system should be done
by a qualified person familiar with PV system
design. The system design is the responsibility
of the PV system designer. Therefore,
FuturaSun does not assume any liability for
how the modules are installed.
Under normal conditions, a PV module is
likely to experience conditions that
produce more current and/or voltage than
reported at STC. Accordingly, the values of
Isc and Voc marked on the module should be
multiplied by a factor of 1.25 when
determining component voltage ratings,
conductor current ratings, fuse sizes, and
size of controls connected to the PV
output. Per NEC, section 8-690 circuit
conductors and over-current devices shall
be sized to carry not less than %125 of the
maximum current as calculated in above.
The FU modules are qualified in protection
class II as for the class of protection against
electrical shock in accordance with IEC
61730-1:2016.
Also note:
•Grounding: If grounding is required by
local law, the module frame or array must
be grounded before wiring. For grounding,
use material that is certified according to
CEI 82/25 or applicable national codes –in
particular the grounding should be
performed by a qualified electrician.
Ensure that the grounding area for the wire
is clean and free from oxides or any debris
that could impede the electrical grounding.
Attach a separate approved ground wire to
one of the holes marked with ground label
on the module frame withan IEC approved
ring terminal or IEC listed grounding lug.
•Voc should be increased by a factor
according to the lowest ambient air
temperatures expected for the installation
site. Refer to CEI 82/25 (for Italy) or Your
local standard for the correct Voc correction
factor according to the respective
temperatures. If this information is not
available, a 1.25 multiplying factor can be
used as default value for correction of Voc.

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•In order to obtain the required electrical
current and/or voltage, the modules can be
connected in series, in parallel, or in a
combination of both.
•In the case of series connection, the Voc is
the relevant value when calculating the total
voltage of the series connection. Do not
exceed the maximum system voltage of
1500 V for the modules FU XXX, even at
low temperatures. Always use the same
type and rating of module in one
installation!
•In the case of parallel connection of
modules or series strings of modules,
fusing may be required.
•Fusing of the circuit shall be determined
according to the local environmental
conditions and regulations. In no case a
FU module string in a parallel shall be
subject to a total reverse current higher
than the Ir value reported in the datasheet.
•The voltage of the strings of modules, in
series, when measured at their poles, is
the sum of all the individual voltages of
each module. This total voltage should be
compatible with therange of input voltages
admissible for the inverter to which the
modules are connected.
8. Use and Maintenance
8a) Intended Use
FU modules are designed for use in grid-
connected systems. They are therefore linked
in series/parallel combinations to feed a
dedicated inverter with a DC input and an AC
output of 230V/380V AC - 50Hz to provide
energy to the local electricity grid.
8b) Operational Measurements
The only two electrical parameters of output
from a PV module, measurable with
conventional instrumentation, are the Voc and
Isc.
When the PV modules are instead connected
in series/parallel configuration to an inverter,
from its display it is possible to read:
•Operational voltage at maximum
power output (Vmpp) of the string
•Operationalcurrent at maximumpower
output (Impp) of the string
From these above values, it is possible to
estimate the voltage at maximum power
(Vmpp) of a module in the string under review
and any non-uniformity in the voltages (Vmpp)
of multiple strings connected to the same
inverter.
From the Impp for the string it is also possible
to verify whether there are obvious differences
between one string and another. When a
uniform condition is detected, it can be
assumed that all the modules are working
properly.
The following measures serve to collect
preliminary information on the operational
status of the PV modules in a PV system.
If there is a need to perform direct
measurements on individual modules using
conventional instrumentation, the following
action should be taken.
To measure the open circuit voltage (Voc):
•Note: even in the presence of an insolation
average of 500 W/m2, a module exposed
to the rays of the sun presents at its poles
(+ and –) a Voc very close to the nominal
value at STC (as shown in Fig.3).
•When taking the temperature at which the
module is working at that moment into
account, the open circuit voltage module
(Vocmod) will be approximately equal to:
Vocmod = VocSTC + [(Tmod –25°C) * Beta ]
Where:
oVocSTC is the open circuit voltage
measured at STC;
oBeta is the % variation of Voc of a
module per 1 °C
o25°C is the reference temperature of
STC;
oIn the case of good solar radiation and
at the ambient temperature (Tamb), one
can estimate the temperature of the
module as follows:
Tmod = Tamb + 30°C
•Using the calculations above, it is possible
when measuring with a multi-meter, to
verify Voc meets the standard shown in the
module datasheet.
•In a case that the Voc to the connectors is
decidedly lower than the standard values
(75% or less) this could represent a

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condition of anomaly which should be
investigated more thoroughly.
To measure the short-circuit current (Isc):
•A PV module exposed to the south,
inclined perpendicularly to the rays of the
sun, in the middle of the day (about 12:00
to 1:00 PM ) and in conditions of good
weather, presents a value of Isc similar to
the rated values at STC, as measurable
with an amp-meter in continuous current.
•By measuring the solar radiation (E)
effective at the moment with a
solarmeter/pyranometer in W/m2the short
circuit current of the module at the moment
Iscmod should be very close to the following
value:
Iscmod = IscSTC x E/1000
Where:
oIscSTC is the short circuit current
measured at STC;
o1000 W/m² is the radiation at STC.
•The measurement of the Isc is executable
with precision only when using a
solarmeter/pyranometer which gives exact
information on the conditions of solar
radiation at the moment, otherwise it is not
reliable.
•In the case of the unavailability of a
solarmeter/pyranometer, it will only be
possible to have an estimate of the
functionality of the module by comparing
the value of Iscmod measured in relation to
those of the other modules of the PV
system, measured under the same
conditions of irradiation.
The acknowledgment of any obvious
discrepancies of Isc in the modules thus
serves to identify anomalies.
•The number of modules in series shall
be calculated reasonably according to
the system configuration and
corresponding rules. The open circuit
voltage under the condition of local
minimum temperatures expected value
cannot exceed the maximum module
system voltage (according to IEC61730,
the max. system voltage of FU modules
are 1000 V and 1500 V, the customer
may calculate according to the voltage
of module) and the required value of the
other DC electrical components. If the
modules are connected in series:
𝐕𝐦𝐚𝐱 ≥ 𝐍 × 𝐕𝐨𝐜 × [𝟏 + 𝛃 × (𝐓𝐦𝐢𝐧 − 𝟐𝟓)]
Vmax = Maximum System Voltage
N= number of modules in series
Voc= Open circuit voltage (refer to product
label or data sheet)
β= Temperature coefficient of Voc (refer to
data sheet)
Tmin= The minimum ambient temperature
The calculation formula shown above shall
be for reference only. The number of
modules that can be connected shall be
determined by a qualified institution or
technician in accordance with the design
specifications of the photovoltaic system
and the local electrical specifications.
8c) Maintenance
⚠In order to ensure proper operation,
performance and reduce fire hazards of the
system, periodic (annual) inspection for
damage to glass and/or cells, and
inspection of the electrical connections
and for corrosion as well as the mechanical
connection is recommended
ATTENTION!!!!!
To avoid the phenomena of electric arcing,
both the connection and disconnection of the
connectors of the modules being tested and
the measurements of Voc should be
performed with the string of modules in
conditions of open circuit. In addition, the Isc
should be measured for each individual
module in conditions of short circuit.
Application class:
Rated as Application Class II per IEC 61730-
1:2016 Hazardous voltage (IEC61730:Higher
than 50V DC, EN61730:Higher
than120V),hazardouspower applications
(higher than 240W) where general contact
access is anticipated (modules qualified for
safety through EN IEC 61730-1 and IEC
61730-2 within this application class are
considered to meet the requirements for safety
class II.

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FuturaSun srl –The specifications in this manual are subject to revisions without further notice
This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
Fuse:
Refer to Product data sheet to find maximum
fuse rating. Fuse rating corresponds to max
reverse current that the module can withstand,
when one string is shaded then the other
parallel strings of modules will be loaded by
the shaded string and current will flow
therefore affects the number of parallel strings.
8d) Cleaning
Under normal conditions (sufficient rainfall),
cleaning of the module is not required. In
extreme climatic conditions, the electrical
performance of the module may be affected by
accumulation of dirt on the glass front cover.
In this case, the front cover can be washed
using water (no aggressive cleaning solutions,
chemicals or abrasives) and a soft cloth,
please see specific instruction below.
⚠CAUTION Exercise extreme caution
when applying water on any electrical
device!
Cleaning Instructions:
Before cleaning process make sure to wear
protective equipment PPE such as protective
gloves, protective glasses and hard hat and
safety shoes.
In case any other tool used for cleaning such
as scaffold make sure to wear all necessary
PPE such as safety belt ,etc.
1. Clean the modules early morning or
late afternoon when solar radiation is
low and the difference temperature
between ambient and modules is not
big especially in hot areas.
2. Do not attempt to clean modules when
the weather is windy and /or ambient
temperature is less than 5C°.
3. Clean the module, more frequently in
dusty Environments, using soft cloth
dry or damp. It is Not recommended to
use water with minerals as this will
leave residues on the surface of the
glass instead using natural water with
PH ranges from 6.5 –8.5.
4. Abrasive material shall not be used for
cleaning.
5. Chemicals are not allowed to be used
for cleaning as this may affect Module
warranty and performance.
6. Modules with broken glass and/or
exposed electrical wires should not be
cleaned as these create electric shock.
7. Do not use aggressive tools for
cleaning , gently clean the modules.
8. Soft foams, non-woven fabrics,
brooms, soft sponges and soft brushes
are permitted.
9. Glass cleaner, alcohol, ethanol or
methanol are only allowed to use in
case of water cannot clean properly.
10. In case of using compressed air , water
pressure shall be at maximum 0.7Mpa
(7 bar) , it is not allowed for any
reason to use higher than this before
consulting Futurasun whenever It is
needed , clean gently and uniformly
circulate the hose without focusing on
any area more than the other.
11. In case of using Robot for cleaning,
Consult Futurasun to check it further ,
brushes shall be soft , in addition glass
and Alu frameshall not be scratched or
damaged during cleaning process ,
robot weight should not be large
affecting the modules , the robot shall
be evaluated to make sure that no
effect or microcracks created from this
cleaning process , any improper use
may infringe module warranty.
12. You May increase the frequency of
cleaning per above procedure
wherever the modules need per the
environment and /or in case of
horizontal mounting where modules
titled 0°angle.
13. In case of Bifacial modules , same
process is applied to clean the
backside gently with soft brushes and
non-abrasive tools.
14. Do not stand, step, walk and/or jump
on modules under any circumstances.
Localized heavy loads may cause
severe micro-cracks at celllevel, which
in turn may compromise module
reliability and void warranty.
15. In case of snowy weather , if snow
removed it has to be removed fully
gently and slightly, it is Not
recommended to remove it partially
this may create difference in load of
glass surface.

14
FuturaSun srl –The specifications in this manual are subject to revisions without further notice
This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
Cleaning Process:
I. Sweep dust and foreign materials by
using dried duster or even mop. It is
important to make sure that dust is not
splattered to the corners of the
modules to avoid any hotspot that may
cause damage to the module. This
step is supposed to be sufficient if
there are no deposits.
II. Scrape Sticky dirt such as but not
limited to bird droppings, leaves, etc.,
should be scraped off with non-woven
fabric or brush. High-hardness tools
are not allowed.
III. Wash for the coloured dirt such as bird
dropping, plant juice, etc. on the glass
surface or dirt that hardly dust off, then
water-cleaning should be used. Water
pressure should be less than 0.7 MPa
( 7 bar).
9. Packaging, Handling and Storage of
Modules
9a) FuturaSun's Packaging
FuturaSun provides the FU modules in the
most appropriate packaging, designed to
guarantee that the transportation and storage
will be in conditions of maximum safety and
protection until the time of installation.
Transport the module in its original
packaging until installation. Protect all parts
of the module during transport and installation
from mechanical stresses.
9b) How to Manage the Packaging
Each package has been designed to allow the
shipment and storage of modules in order to
maintain their integrity unchanged over time,
provided that the information and indications
supplied by FuturaSun are closely observed
and followed. These indications are
summarised by a series of standard symbols
posted in a visible manner on each pallet. The
list below illustrates the meaning of each
symbol (you can find some of them in each
pallet):
DO NOT STACK: each pallet of
modules is packaged according
to the maximum number of
modules stackable vertically, in
order to avoid or reduce
mechanical stress or damage as a result of the
pressure exerted by the stacked modules.
Therefore, it is absolutely forbidden to stack
more than one pallet on top of another, both in
the process of shipment and storage of
modules.
DO NOT EXPOSE TO
ATMOSPHERIC AGENTS: each
pallet of modules is suitably
dressed in a cap of transparent
plastic in order to avoid temporary
contact with generic water spray or
atmospheric agents. The plastic casing does
not ensure the protection of the modules in the
case of prolonged exposure to atmospheric
agents. Similarly, in the case of flooding, the
pallet does not ensure the maintenance of the
mechanical properties of the weight of the
modules. For this reason it is recommended to
store the pallet in a place that is sheltered and
dry. In addition, as the junction box has an
IP68 degree of protection, in the event of a
flood the stagnant water inside of the frame
could oxidise the metal contacts of the
connectors degrading the characteristics and
altering the electricalproperties ofthe contacts
of the module causing damage.
DO NOT OVERTURN THE
PACKAGING: the packaging is
only designed to be handled and
stored with the modules
maintaining the position of the
arrow printed on the packaging, with the arrow
always facing upwards. Not following these
indicated directions may create forms of
mechanical stress on the modules that could
cause damage or breakage.
RECYCLABLE: most of the
photovoltaic modules are
recyclable. They should not be
thrown into landfill without a
proper method for recycling.
Aftert the approval ofEU Directive 2012/19/Ue
the photovoltaic modules are classified as
electronic waste.

15
FuturaSun srl –The specifications in this manual are subject to revisions without further notice
This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
FRAGILE: the photovoltaic
modules are manufactured
using a glass front which makes
up approximately 70% of the
total materials used to construct
them. Although the modules are stiffened by
an aluminium frame, any direct impact to the
glass or on the corners of the modules should
be avoided. Avoid flexing the laminates or
applying non distributed loads and stresses.
Avoid scratching the surface of the exterior
glass or backsheet. Do not apply any forces to
the backsheets.
HANDLE WITH CARE: during
the operation of shipping and
storage of the modules use
maximum care to ensure the full
integrity of the modules.
9c) How to Handle the Pallet
During the handling of the pallet make sure to
pay the utmost attention. The packaging must
be raised/moved exclusively with fork-lift
trucks or hand pallet trucks fitted with forks of
length appropriate to its size and weight.
Pay attention during the stages of handling
and unpacking. Verify that the package is
positioned on a surface that is either flat or not
excessively deformed to a point that would
impart an inclination to the pallets which could
damage the PV modules.
FuturaSun DOES NOT ASSUME
RESPONSIBILITY IN THE EVENT OF
DAMAGE TO THE MODULES ARISING
FROM MANAGEMENT OF THE PACKAGING
THAT IS IMPROPER OR DIFFERENT FROM
WHAT WAS STATED IN THIS DOCUMENT.
9d) Unpacking
Observe the following procedures for the
unpacking of modules:
•Place the packaging on a stable and
flat surface
•Using a cutter, cut the plastic wrap
surrounding the package or to open
the paper box
•Remove the plastic wrap
•Remove the upper cover
•Recover the flash list (for record
keeping)
•Using a cutter, cut the straps
•Remove the PV modules and their
protective corners without damaging
Note: avoid storing partial packaging!
Once you have removed the strapping the
packaging must no longer be moved!!
9e) Recycling
Meaning of crossed-out wheeled dustbin: Do
not dispose of electrical appliances as
unsorted municipal waste, use separate
collection facilities. Contact your local
government for information regarding the
collection system available. If electrical
appliances are disposed of in landfills or
dumps, hazardous substances can leak into
the groundwater and get into the food chain
damaging your health and well-being.

16
FuturaSun srl –The specifications in this manual are subject to revisions without further notice
This document applies to modules Silk®Plus Duetto / Silk®Premium Max Duetto series.
FuturaSun srl Riva del Pasubio, 14
35013 Cittadella (PD) - Italy VAT N°
IT04635940283
Tel. [phone]
www.futurasun.com
[email protected]