Electrical Connection SMA Solar Technology AG
40 SB20_25_30HF-IEN102911 Installation Guide
Load Disconnection Unit
You must install a separate line circuit breaker for each inverter in order to ensure that the inverter
can be securely disconnected under load. The maximum permissible rating is located in
section13”Technical Data” (page83).
Detailed information and examples for the rating of a line circuit breaker can be found in the Technical
Information "Line Circuit Breaker" in the SMA Solar Technology AG download area at
www.SMA.de/en.
DANGER!
Danger to life due to fire.
When more than one inverter is connected to the same line circuit breaker, the protective
function of the line circuit breaker is no longer guaranteed. It can result in a cable fire or
the destruction of the inverter.
• Never connect several inverters to the same line circuit breaker.
• Comply with the maximum permissible fuse protection of the inverter when selecting
the line circuit breaker.
DANGER!
Danger to life due to fire.
When a generator (inverter) and a consumer are connected to the same line circuit
breaker, the protective function of the line circuit breaker is no longer guaranteed. The
current from the inverter and the grid can accumulate to overcurrent, which is not detected
by the line circuit breaker.
• Never connect consumers between the
inverter and the line circuit breaker
without protection.
• Always protect consumers separately.
NOTICE!
Damage to the inverter by using screw type fuse elements as a load
disconnection unit!
A screw type fuse element, e.g. D system (Diazed) or D0 system (Neozed) is not a load
disconnection unit, and thus must not be used as a load disconnection unit. A screw type
fuse element is only used as cable protection.
When disconnecting under load using a screw type fuse element, the inverter can be
damaged.
• Use only a load disconnection switch or a line circuit breaker as a load disconnecting
unit.