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© 2011-2013 Silfab Ontario Inc. - Specifications in this manual are subject to revisions without notice
SAFETY AND INSTALLATION MANUAL FOR
PHOTOVOLTAIC MODULES
1. General Information
The photovoltaic
(PV)
modules
SILFAB
SLAXXXM3A/SLAXXXM, SLAXXXP3A/SLAXXXP (‘SLA’)
and SLGXXXM3G/SLGXXXM, SLGXXXP3G/SLGXXXP
(‘SLG’) are devices that produce electrical energy
by converting the sunlight’s radiation reaching
their surface, when appropriately exposed, into
continuous/direct current (DC).
The SLA/SLG modules are intended to be used
only and exclusively in photovoltaic module
systems connected to the electrical grid;
therefore, it is not recommended to use them in
battery powered photovoltaic module systems
(stand alone).
The rated currents at Standard Test Conditions
(STC) of the SLA/SLG 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,
ammeter, 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 SLA/SLG
modules, of technical importance during the
operation, installation and maintenance, are the
following:
•
Voltage at open circuit (V
oc
)
•
Current at short circuit (I
sc
)
•
Voltage at point of maximum power (Vp
max
)
•
Current at point of maximum power (Ip
max
)
•
Solar radiation in W/m
2
at the time
•
Temperature of the cells
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.
Fig. 1: IV curve at different irradiance
Avoid any shading caused by obstacles in and
around the area of installation as shading can
cause loss of output.
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.