Fronius IG Plus 3.0-1 - Solar Module Ground at Positive Pole: Connecting Combined Solar Module Strings Using a DC String Input Combiner; General; Additional Required Components; Solar Module Ground at Positive Pole

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Solar Module Ground at Positive Pole: Connec-
ting combined Solar Module Strings using a DC
String Input Combiner
The following work steps are only necessary when the solar module ma-
nufacturer requires a solar module ground at the positive pole.
When more solar module strings are combined to one solar module string
prior to the inverter, the solar module string current may exceed the per-
missable DC input terminal current rating of 20 A.
In this case the DC cables can be connected to the Fronius IG Plus using
a string input combiner as an option.
General
Additional required components
Option
Additional
Required
Components
- 2 string input combiners
(available from Fronius as an
option)
- cable lugs
select cable lugs that match the
available DC cables
- hexagon screws
- hexagon nuts
matching the cable lugs
The following additional components are required for connecting combi-
ned solar module strings using a DC string input combiner:
Solar Module
Ground at
Positive Pole
=
~
=
~
DC+
DC-
Inverter
L1
N
GND
Solar module
Solar module ground at positive pole with fuse
DC main switch
GFDI fuse
String fuse
L2
L3