Information On Earthing/Equipotential Bonding; Connecting The Modules - Viessmann Vitovolt 300 Installation And Service Instructions Manual

Electrical connection
Parallel connection:
■
The current can be increased by connecting the
modules in parallel. To do this, the positive terminal
of one module is connected to the positive terminal
of the next module. The total current is the sum of
the individual currents.
Observe the maximum reverse current load (use line
fuses if required) and the maximum permissible input
current of the inverter.

Information on earthing/equipotential bonding

■ Professional earthing or equipotential bonding of the
PV modules is required in line with country-specific
regulations and statutes.
For earthing, establish a conductive connection
■
between the module frame and earth.
■ When removing a PV module from the power circuit,
the earth cable for the other PV modules must not be
disconnected. The module terminals provide no
earthing function.
A B C D
G F E
Earth cable
A
Module frame
B
Serrated washer
C
Nut ( M4)
D ≥
Screw ( M4)
E
≥
Cable lug
F
Equipotential bonding
G

Connecting the modules

Subject to system size:
■
Never exceed the maximum number of PV modules
per string.
If several strings are installed, ensure that each
string comprises the same number of modules.
■ The correct routing of cables is an important safety
measure to protect against induced voltage surges.
Route positive and negative cables as close
together as possible, so that the area created by
this power circuit and the resulting induced overvolt-
age remain minimal.
■ Ensure that all plug-in connections are seated pre-
cisely.
(cont.)
!
To prevent overheating, select a cable cross-section
■
and connection capacity that is appropriate for the
maximum short circuit current of the system.
Recommended cable cross-section: 4 mm
Recommended rated current for one connecting
plug: 1 A
>
Protect the plug-in contacts against contamination
■
and damage and never separate them under load.
■ To provide earthing, use a suitable type of connec-
tion for the earth conductor.
The holes drilled in the frame can be used to make a
■
secure electrical connection to the PV modules.
Please note
Lightning strikes may damage the PV system.
When routing string lines, minimise the surface areas of
the conductor loops. This reduces the risk of indirect
lightning strikes.
Installation sequence
2
7