SMA SB 3300TL Installation - Manual (Page 17)

SMA Technologie AG Requirements for the Installation
Installation Guide SB3300TL-11:SE2006 Page 17
The Sunny Boy 3300TL does not generate any extraordinary capacitive discharge
currents in normal operation. In certain cases (e.g. the internal testing of the safety
components within the Sunny Boy 3300TL) discharge currents can occur that can trip
a 30 mA GFCI.
The system impedance at the installation site of the Sunny Boy 3300TL must be less
than 1 Ohms for the islanding detection and the fuses to work porperly. Furthermore
you should have a suitable cable cross-section in order to keep the losses below 1 %
at nominal power. The according losses with respect to cable length and cross-section
are illustrated below. It shows a multi-conduit cable with all conduits made of copper.
The maximum cable lengths for the different cable cross-sections are as follows:
Install a 100 mA GFCI in the AC distribution in case an additional GFCI is ab-
solutely necessary.
Conductor cross-section 4.0 mm² 6.0 mm² 8.0 mm² 10.0 mm²
Max. length 18 m 28 m 37 m 47 m
Do not use cable specification with losses above 1.0 %
Length
Lo
sses