SMA SI-TB-BOX-10 - Manual (Page 19)

SMA America, LLC 4 Product Description
Installation Manual SI_TDBOX-IA-eng-IUS122211 19
4.5 Miniature Circuit-Breaker
The miniature circuit-breakers protect the connected conductors against destruction due to
overheating. Each of the miniature circuit-breakers can be manually activated or can be tripped
automatically.
To be able to trip automatically, each miniature circuit-breaker monitors the electric current in the
connected conductors. When the current becomes too high, the miniature circuit-breaker interrupts the
flow of current and thus prevents overheating of the conductors.
Figure 5: Overview of the miniature circuit-breakers
Position Description Explanation
A Upper switch position The miniature circuit-breaker is closed.
B Lower switch position The miniature circuit-breaker is open.