SMA Sunny Island 2012 Technical Description page 128

Battery management
Level 2: The second level of the battery preservation mode ensures that the Sunny Island is started
regularly every two hours only in the time period during which energy supply is expected, and that
it attempts to charge the battery from the AC side. In case of PV systems this time is during the day.
In this case, you define the start time using the "223.03 BatPro2TmStr" parameter and the stop time
using the "223.04 BatPro2TmStp" parameter.
Level 3: The third level ensures that the battery is protected from deep discharge and thus against
damage. In this case, the Sunny Island is switched off completely. To start the inverter, see section
10.1.5 "Restarting the System after Automatic Shutdown" (Page 88).
At all three levels, the Sunny Island is stopped only if no battery current flows within 5 minutes (limit:
3 A charging current).
The limits for all three levels can be set independently from each other. This allows individual levels
to be skipped.
Information
If the BatPro1Soc parameter < BatPro2Soc, level 1 is skipped and only level 2 is
conducted.
For level 1 and 2, a hysteresis of 5% of the SOC charge level is designated for exiting this state.
Battery preservation mode is not exited automatically if an external voltage source (grid
reconnection) is present.
128 SI2012_2224-TEN082311
SMA Solar Technology AG
Technical Description