SMA SUNNY BOY 1700, Installation Manual

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SMA Technologie AG Installation requirements
Installation Guide SB1700-11:SE2006 Page 17
The system impedance at the installation site of the Sunny Boy 1700 must be less than
1 Ohms for the islanding detection and the fuses to work porperly. In addition, we
recommend dimensioning the cable cross-section so that line losses do not exceed 1%
at the nominal power. Line losses depending on the cable length and cross-section
are shown in the graph below. It is based on a multi-conduit cable with all conduits
made of copper.
The maximum cable lengths for the different cable cross-sections are as follows:
Cable cross-section 1.5 mm² 2.5 mm²
Max. length 15 m 22.5 m
0,0%
0,2%
0,4%
0,6%
0,8%
1,0%
1,2%
1,4%
Cable length
0 m
10 m 15 m 20 m 25 m 30 m 35 m 40 m 45 m 50 m 5 m
Loss
1.5 mm²
2.5 mm²
Do not use cables where the losses will exceed 1.0 %