SMA SUNNY STRING-MONITOR Technical Description page 33

SMA Solar Technology AG
Figure 12: Relationship between cable length, number of Sunny String-Monitor connected and cable cross-
section.
Example: Dimensioning a Connection Cable
In order to achieve secure tripping, the minimum cross-section of the connection cable must be
determined. The cable cross-section to be selected depends on the number of connected Sunny
String-Monitor, the cable length to the voltage supply and the cable lengths between the connected
Sunny String-Monitor.
In a PV plant there are 20 DC switches. The greatest distance between the Sunny String-Monitor or
the voltage supply is 150 m.
According to figure 12 the cable cross section must be at least 4 mm
Technical Description
5 Electrical Connection
2
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SSM-TEN103132 33