8
6.2.1
Weather protection
HINWEIS
• Lay the cables so that they exit the junction box
from below. This prevents water, which runs along
the cable, from collecting at the point where the
cables exit the junction box.
• For PV modules mounted horizontally, lay the cables
in a U-form away from the junction box.
• PV modules mounted vertically do not usually need
any additional adjustments.
Fig.2
U-form cables at the junction box for a horizontally
mounted PV module
Lay cables carefully to protect against damage from:
• Direct environmental factors, such as precipitation
• movement (e.g. from wind)
• Indirect environmental factors, e.g. snow or ice,
which slip down behind the modules, and
• Chafing on the insulation due to the cable moving
(e.g. from wind or ice)
6.3
Potential equalisation (earthing) of PV
module frames
HINWEIS
• Local regulations may specify potential equalisation
(earthing).
• When earthing the PV module frame, establish a safe
electrical connection to the earth potential or
earthed sub-structure.
• Observe the requirements and recommendations
of the inverter manufacturer, as well as insurance
policies.
• The PV module frames are made of aluminium.
When mounting onto other materials, take suitable
measures to prevent electric corrosion, e.g. by using
a coating.
HINWEIS
Potential equalization does not serve as lightning
protection. Lightning protection may be necessary
in addition
to potential equalization.
6.4
Lightning protection
WARNING!
Absence of or inadequate lightning protection.
Risk of fire or electric shock!
Leave the planning and installation of the external,
and if required internal, lightning protection to be
carried out by qualified technicians at all times.
• It is essential to integrate an arrestor for connecting
the lightning rod with the lightning protection. This
ensures the safety and reliability of the lightning
protection as well as the photovoltaic system.
• Do not under any circumstances include the PV
module frame or its earth as an active part of the light-
ning protection (e.g. as a lightning arrestor)
If you earth the PV module frame, the only task of this
earth is the potential equalisation between the PV
module frame and the supporting structure.
6.5
Parallel and serial connection
PV modules of the same type can be connected in
parallel. The PV modules in this series are fundamen-
tally designed for series connection.
Only use PV modules of the same type and output
for parallel connection. Take measures for over-
current protection (e.g. line fuses) if necessary.
Never exceed the specified reverse current
loadability of the PV modules. Maximum number
of module strings that are allowed to be switched
in parallel : 2 (fuse rating / (short-circuit current
x1.25)+1)
Make sure that only PV modules with the same
amperage (Impp) are interconnected for series
connection and make sure that the voltages of
lines connected in parallel are the same. Even at
low temperatures, never exceed the maximum
permissible system voltage of the PV modules.
Maximum number of PV modules that are allowed
to be switched in series ; maximum system volt-
age / (open circuit voltage x 1.25), with respect to
the temperature coefficient.
Make sure that the number and connection of the
PV modules match the electrical values specified
by the devices connected to the photovoltaic sys-
tem.
Make sure that the polarity is correct.
7
Details of mechanical mounting
7.1
Aligning the mounting profiles
7.1.1
Permissible alignment
