Sonnen sonnenBackup-Box, Operating Instructions For Operators

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Operation | 4
KD-493 | 22324 | EN | X00 11 / 20
4.1.2 Backup operation - grid outage
5 20
40
60
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100
ON AL
Test
Reset
R
AL
kΩ
1
2 3
7
5
9
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+
F1
SPV
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3
I
0
off off off
4
8
3
L1 L2 L3
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Illustration 2: Backup operation - grid outage
1 PV system 7 Storage system
2 Inverter of the Backup-Box 8 Battery of the storage system
3 Backup-Box 9 Public electrical mains
4 Consumer connected to phase L1
5 Consumer connected to phase L2
6 Consumer connected to phase L3
The Backup-Box (3) automatically detects a grid outage. As soon as the voltage
of the electrical mains drops to approx. 180 V, the connection to the public elec-
trical mains (9) and to the PV system (7) is disconnected.
Backup power is generated after approx. 3 seconds. In this case, the direct cur-
rent of the battery of the storage system (8) is converted into alternating current
using the inverter of the Backup-Box (2). The consumers connected to the phase
L1 in the house (4) are thereby supplied with electrical power. Consumers con-
nected to the phase L2 (5) or L3 (6) will not be supplied with electrical power.
The storage system with Backup-Box switches from backup to grid operation as
soon as the public electrical mains (9) start to deliver electrical power again.
Automatic stop of the backup operation
The storage system with Backup-Box generates electrical power until a minimum
state of charge of the battery is reached. Thereafter, no further discharge is al-
lowed.