16
to another with opposite polarity, irreversible
damage can be caused to the PV module product.
Be sure to confirm the voltage and polarity of each
string before making a parallel connection. If
measurements reveal opposite polarity or a voltage
difference greater than 10V between the strings,
check
their
structural
configuration
before
proceeding with the connection.
The number of modules connected in series and
parallel should be reasonably designed according to
the system configuration.
PV modules with different electrical performance
models cannot be connected in one string.
The system shall use special cables and connectors
for PV system and ensure that all connections are
securely fastened. The cable must be 4mm
2
(i.e. 12
AWG) and withstand the maximum possible
open-circuit voltage of the PV system.
When fixing the cable to the rack, it is necessary to
avoid mechanical damage to the cable or to the PV
module. Do not press the cable hard. To secure the
cable to the rack in the proper way, specially
designed UV-resistant coils and cable clips must be
used. Avoid direct sunlight and water soaking to the
cable.
Keep the connectors dry and clean and make sure
that the nuts on the connectors are tightened before
connecting them. Do not connect the connectors
when they are damp, contaminated or in other bad
conditions. Avoid exposing connectors to direct
sunlight and soaking in water. Avoid the connectors
falling on the ground or the roof. Do not plug or
unplug the connectors when the PV module is in
live state. When it is necessary to remove the
connectors, ensure that the PV module is not in
working condition and that professional unlocking
tools and safety measures are used. Direct dragging
and pulling is forbidden.
The junction box of the PV module contains bypass
diodes connected in parallel to the string of the PV
module. The bypass diode in the junction box
prevents module degradation due to shading or
covering. Refer to the junction box diode
specification provided in the relevant product
datasheet for more details. I When the localized hot
spot phenomenon occurs in the PV module due to
partial shading or coverage, the diode in the
junction box will start to work, so that the module
current will no longer flow through the hot spot cell,
so as to limit the heat and loss of the PV module.
When a diode failure is suspected or found, please
contact Chint Solar and do not attempt to open the
junction box cover.
6.3
Grounding
The PV modules are designed with an anodised,
corrosion-resistant aluminum alloy frame as a rigid
support. To ensure safety and to avoid lightning strikes
and electrostatic damage to the PV modules, the PV
module frame must be earthed. The earthing device
must be in full contact with the interior of the
aluminum alloy of the frame, penetrating the surface
oxide film.The following is the specific grounding
method, as shown in Fig. 15.
