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FuturaSun srl – The specifications in this manual are subject to revisions without further notice
1. General Information
The photovoltaic (PV) modules, FU XXX P, FU
XXX M, (hereafter “FU XXX”) 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 (V
oc
) with tolerance
of ± 4%
•
Current at short circuit (I
sc
) with tolerance of
± 5%
•
Voltage at point of maximum power (Vmpp)
•
Current at point of maximum power (Impp)
•
Power (P
max)
with tolerance of ± 3%
•
Solar radiation in W/m
2
at 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
and
their
surface
exposed
as
perpendicularly 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.
In order to optimize the production of electical
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, with the tilt angle (β) (inclination of the
surface of the modules in respect to the ground, as
shown in Fig.2) 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.
East
b
South
Fig.2
