Sunny Island 4500
Installation & Operating Instructions
BWRI45-13-EE0304
- 26 -
SMA Regelsysteme GmbH
2.2.2 Battery
States
The battery management determines the state of the battery out of a selection of
eleven possible battery states. It informs the relay control about the determined bat-
tery state. The most dominant input variable which is most important for the calcula-
tion of the battery state is the actual state of charge (see Fig. 2.6). This mainly pro-
vides information on the availability of the battery. In addition to the state of charge,
however, other variables mainly concerning battery aging are also used for calcula-
tion. These are e. g. the battery voltage during overcharging or exhaustive discharg-
ing, but also the times after a full charge or an equalizing charge has first been re-
quested. The battery state therefore shows that either the availability of the energy
stored deteriorates considerably due to the decreasing state of charge or the battery
is in an area with increasing aging while its state of charge can still be high.
battery low
Battery Requires
Charging!
battery
normal
battery
overloaded
01
02
03
N4
N3
N2
N1
L1
L2
L3
L4
Range
Battery State
State of Charge
Start Battery Charging
With Generator
Partially deactivate
Consumers
Deactivate all
Consumers
Deactivate
Sunny Island
Deactivate Wind Power Plant
Activate
Dumpload
50 %
60 %
10 % 20 %
40 %
0 %
100 %
30 %
Fig. 2.6:
Battery states, states of charge and suggested switching operations