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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
module at the moment I
scmod
should be very
close to the following value:
I
scmod
= I
scSTC
x E/1000
Where:
•
I
scSTC
is the short circuit current
measured at STC;
•
1000 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 I
scmod
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 I
sc
in the modules thus serves
to identify anomalies.
•
NOTE: an excess of intensity due to
meteorological phenomena (for example,
lightning) or mistakes in the connection (for
example, connecting the modules under full
irradiance) can cause damage, or short-circuit
of the bypass diodes contained in the junction
box. As a result, the Voc of the module may
decline in proportion to the damaged diodes to
⅔
Voc,
⅓
Voc, or 0V.
In this case, the bypass
diodes must be substituted only by Silfab
personnel, onsite or offsite at Silfab’s sole
discretion.
8c) Maintenance
Although PV modules do not require any routine
maintenance, periodic (annual) inspection for
damage to glass and inspection of the electrical
connections and for corrosion as well as the
mechanical connection is recommended.
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, dust or debris on the glass front cover.
In this case, the front cover can be washed using
water or commercial glass cleaners, alcohol/
ethanol/methanol and a soft cloth.
Do not use abrasive brushes, powders, cleaners,
polishers, sodium hydroxide, benzene, nitro-
thinners, acid or alkali and other chemical
substances. Doing so may damage the anti-
reflective coating that is present on the glass of
some Silfab modules.
Most municipal water used as cleaning water;
however, it is not recommended to use water with
high mineral content as it may deposit on the glass
surface when the water is dry. The pressure of the
cleaning water should be less than 690Kpa.
Exercise extreme caution when applying water
on any electrical device!!
The module cleaning should be done in the early
morning, in the evening, at night or on rainy days.
When cleaning in the morning or evening,
select the period when sunshine is not strong.
If you need to clear snow to improve output
power, use a soft brush to gently remove the
snow. But do not try to remove frozen snow or ice
on the modules as it could lead to property
damage.
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 V
oc
and I
sc
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 open circuit
and not to the extreme poles of the string, which
could be affected by voltages up to 600V.
