SMA AUTOMATIC SWITCH BOX L - Manual (Page 19)

SMA Solar Technology AG Electrical Connection
Installation Guide AS-BoxL-IEN084410 19
5.2.1 Sizing the lead fuse
Use the table to select the condition that applies to you and observe the corresponding SMA Solar
Technology recommendation.
Load disconnection unit
Use only line circuit breakers as load disconnection units!
A screw type fuse element, e.g. D system (Diazed) or D0 system (Neozed) is not a load
disconnection unit and therefore may not be used as one.
Upon disconnection under load, the screw type fuse elements of the Automatic Switch Box
may be destroyed, or its function may be inhibited by contact burning. They only protect
the cables.
Condition Recommendation
The rating of the back-up fuse in the
distribution is equal to the nominal
current of the Automatic Switch Box
during grid operation (63 A). • Insert a fuse with a nominal current of 63 A into the
"F5 Backup Loads" fuse element.
The rating of the back-up fuse in the
distribution is lower than the nominal
current of the Automatic Switch Box
during grid operation (63 A). • Install a fuse with the same nominal current as in the
distribution into the "F5 Backup Loads" fuse element.
• Use Sunny Backup parameter 232.02 GdCurNom
to set the maximum grid current to the value of the
back-up fuse.
The rating of the back-up fuse in the
distribution is higher than the nominal
current of the Automatic Switch Box
(63 A). • Insert a fuse with a maximum of 63 A into the "F5
Backup Loads" fuse element in accordance with the
installation.
• Install a fuse with max. 63 A in the distribution.