aleo
aleo solar Deutschland GmbH
| Osterstraße 15| 26122 Oldenburg | Germany | [email protected]
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installation instructions Edition 01/2012 en-GB-Intl (120508b)
CAUTION
aleo modules are suitable for a maximum
system voltage of 1000 V. Details on the
maximum system voltage for a certain
module type can be found on the product
label or on the corresponding data sheet.
Local regulations may stipulate a lower
voltage. Other components of the system
may also require a lower maximum voltage.
Design the system in such a way that the
maximum system voltage is not exceeded,
even in the worst case scenario, e.g. a
photovoltaic generator with the current
switched off, low outdoor temperatures, and
strong irradiation.
As a rule of thumb, multiply the open circuit
voltage under standard test conditions (STC)
by a safety factor of 1.25 (see Appendix A,
'Parameters of aleo Modules'). Regional
regulations may stipulate multiplying by a
different factor.
5.12.1.
Wiring
NOTICE
Avoid cross connection
3
of the modules. A cross con-
nection is, in practice, a frequent source of faults as it
leads to more complex wiring.
5.12.2.
Wiring and lightning protection
NOTICE
Plan the laying of the cables so that the cables of a
circuit span as small an area as possible. This mini-
mises the likelihood of damages in the event of a
lightning strike in the area.
The smaller the area that the wiring takes up, the smaller the
voltage that the magnetic field of a lightning current (e.g.
through a nearby lightning conductor) induces in the con-
ductor loop (of the module string circuit).
Lay all the cables of the module string as follows:
form as small loops as possible
lay loops next to one another with alternating
current directions
lay the return circuit of the string as close to the
outgoing circuit as possible.
3
In a cross connection, the modules of a string, e.g. made up
of 8 modules, are connected in a 1, 3, 5, 7, 8, 6, 4, 2 order.
Or, more simply: on the 'way there', every second module is
connected (1, 3, 5, 7), on the 'way back' the modules not yet
connected are then connected (8, 6, 4, 2).
More careful wiring can pay off in a lower potential for
damage. More details on this kind of wiring can be found in
Appendix C, 'Optimisation of Wiring for Lightning Protection'.
5.12.3.
Connection and system voltage
NOTICE
As a rule, keep the system voltage low. This reduces
the voltage load of the electrical components and
can lead to a longer service life.
If necessary, divide a long module string into
numerous strings with the same number of modules
and connect these shorter module strings in
parallel.
5.12.4.
Cable properties
Only use cables that have been approved for use in photo-
voltaics. This means, for example, that:
the insulation of the cable is approved for the
maximum open circuit voltage
the cable material is compatible with the modules
as well as their connectors and cables (forgoing use
of softeners)
the cable casing can withstand the expected stress
loads:
temperatures
temperature changes
moisture (above all humidity)
mechanical loads
UV-radiation
ozone ([17]).
aleo recommends using only halogen-free cables. Locally valid
regulations may also stipulate their use, for example in
interior spaces.
Information about cable properties can be obtained from the
cable manufacturers.
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ID A
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