SMA SB 4200TL HC Multi-String - Manual (Page 18)

Installation Requirements SMA Technologie AG
Page 18 SBTLHCMS-IEN080411 Installation Guide
The Sunny Boy does not generate any extraordinary leakage currents in normal oper-
ation. In some operating states (e.g. during self-test of the protection units) discharge
currents can occur which would trip a standard 30 mA RCD or ground fault circuit in-
terrupter.
5.3. 1 Line Losses
AC cable system impedance should not exceed 1 ohm. This is necessary, amongst other
things, for the correct operation of impedance observation. In addition, we recommend
dimensioning the conductor 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. Multi-wire cables with copper forward and return conductors are
used.
Sunny Boy SB 4200TL HC Multi-String
The maximum cable lengths for the different cable cross-sections are as follows:
In case an RCD or ground fault circuit interrupter is imperative, you must use a
circuit breaker with a sensitivity of 100 mA or more.
Cable cross-section 6.0 mm² 8.0 mm² 10.0 mm²
Max. length 22 m 30 m 37 m
Do not use cables where the losses will exceed 1.0 %
Cable length
Line Losses