AEG 8000012364 BAL User Manual

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"UniVert 2" inverter 
 
Page 11 of 42 
8000012364 BAL, en 
Individual INV operation: 
Here an INV is supplied with DC and itself supplies the AC load. In 
the event of INV fault or switch-off, the load is no longer supplied. 
Parallel INV operation: 
In order to increase redundancy or performance, up to 8 INVs of the 
same type and the same output can be connected in parallel. Note 
that if one or several of the INVs fail, the remaining INVs take over 
the load. Overload of the remaining INVs can be prevented by 
choosing the right number of redundant INVs. If the number of INVs 
that fail or are switched off exceeds the number of available 
redundant INVs, the remaining INVs switch off together. 
When the INVs are switched back on by connecting the DC, they do 
not switch on their output contactors at the same time until a sufficient 
number of INVs (in accordance with the redundancy setting) are 
available to take over the load.  
INVs for parallel operation need a choke between INV output and 
busbar.  
Individual or parallel operation with SBS: 
If one or more INVs are combined with an SPS, switchover of the 
loads from the mains to the INV and vice versa is possible without 
any interruption. With parallel operation systems, the load is 
distributed to the remaining INVs if one or several INVs fail. The 
system may switch over to the mains when a voltage drop occurs on 
the load busbar as a result of the failure of one INV, or if the number 
of INVs still operating is insufficient (redundancy setting). In order to 
switch the load back from the mains to the INVs, n-R INVs must be in 
operation (where R = redundant INVs). 
2.2 
Function of the System 
Individual INV operation: 
The INV as an individual unit supplies the loads. If it is switched off or 
disturbed, either by internal faults of the INV or by failure of the 
DC supply or by a DC voltage deviation, the AC loads are no longer 
supplied. The INV is not synchronised with the mains or other 
AC voltage sources. The INV can be connected to the DC voltage 
using a switching device on the input (miniature circuit-breaker, 
contactor). An internal softstart device limits the current to values 
below the rated current. If the INV is switched to the DC, the control 
unit starts operating. The INV supplies the output voltage if the unit is 
additionally switched on using the ON/OFF switch. If the supplying 
mains fails, the battery of the power supply system is discharged 
(also) by the INV. When the DC undervoltage monitoring value is 
reached, the INV is switched off. If the battery is charged after the 
mains voltage has returned, the INV is automatically started when a 
limit value of the DC undervoltage monitoring is exceeded.