31
NOTE
For optimal functioning of grid monitoring the resistance
in the leads to the AC side connection terminals must be as low
as possible.
The AC conductor resistance between the Fronius IG Plus unit
and the building’s distribution panel should not exceed 0.5 Ohm.
Monitoring the
Grid
For larger photovoltaic schemes it is possible to connect several Fronius
IG Plus units in parallel without any problems.
To ensure symmetrical feeding, connect the inverters uniformly to all
phases.
NOTE
The Fronius IG Plus is designed to be connected to
three phase systems. Utilities generally allow up to 6 kVA of
unbalance but check with your utility and try to balance the instal-
lation. The connection to the grid shall be done in the following
way:
208 V / 240 V:
-
Connect Fronius IG Plus No. 1, No. 4, No. 7, ... to L1 and L2
-
Connect Fronius IG Plus No. 2, No. 5, No. 8, ... to L2 and L3
-
Connect Fronius IG Plus No. 3, No. 6, No. 9, ... to L1 and L3
277 V:
-
Connect Fronius IG Plus No. 1, No. 4, No. 7, ... to L1 and N
-
Connect Fronius IG Plus No. 2, No. 5, No. 8, ... to L2 and N
-
Connect Fronius IG Plus No. 3, No. 6, No. 9, ... to L3 and N
Schemes with
more than one
inverter
NOTE
Do not connect
Fronius IG Plus inverters
to the 480 V Delta power
grid.
48
0 V
48
0 V
480 V
12
0
°
12
0
°
120
°
L1
L2
L3
=
~
=
~
=
~
480 V Delta
Overview of
Available
Power Grids
(continued)
Summary of Contents for IG Plus 12.0-3
Page 2: ......
Page 4: ...ud_fr_st_et_01382 012008...
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Page 16: ...6...
Page 17: ...7 General Information...
Page 18: ...8...
Page 24: ...14...
Page 25: ...15 Installation and Startup...
Page 26: ...16...
Page 80: ...70...
Page 81: ...71 Operation...
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Page 123: ...113 Troubleshooting and Maintenance...
Page 124: ...114...
Page 149: ...139 Appendix...
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