Huawei Backup Box-B0 Quick Manual page 9

The sequence of connecting the cables to a single-phase Backup Box and to the AC terminals L,
N, and PE on the inverter must be the same. The sequence of connecting the cables to a three-
phase Backup Box and to the AC terminals L1, L2, and L3 on the inverter must be the same.
Otherwise, the device cannot work properly. (As shown in the following figures, connect the
cables to a single-phase Backup Box in the sequence of L, N, and PE from left to right, and
connect the cables to a three-phase Backup Box in the sequence of L1, L2, and L3.)
Backup Box-side terminal (single-phase)
Backup Box-side terminal (three-phase)
Installing a Short-Circuiting Plate
3.6
Inverter-side terminal (single-phase)
Inverter-side terminal (three-phase)
8
X3