13 Battery Management
SMA America, LLC
114
SI4548_6048-US-TB_en-13
Technical description
Level 3:
The third level ensures that the battery is protected from deep discharge and thus protected
against damage. In this case, the Sunny Island is switched off completely.
• To recommission the Sunny Island, restart it (see Section 9.5 "Reactivating the Device Following
Automatic Shutdown", page 75).
At all three levels, the Sunny Island is stopped only if no battery charging current flows within ten
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.
Battery preservation mode levels 1 and 2 are automatically exited as soon as an external voltage
source (grid reconnection/generator start) is present at the AC2 terminal. For exiting these levels, a
hysteresis of 5% of the state of charge is provided.
Only battery preservation mode of level 3 is not automatically exited if an external
voltage source (grid reconnection/generator start) is present.
The battery preservation mode can be exited by manually starting the Sunny Island. If, within ten
minutes (see above), charging current is detected, the Sunny Island continues to operate; otherwise,
it switches off again.
Parameter BatPro1Soc < BatPro2Soc
If the BatPro1Soc parameter < BatPro2Soc, level 1 is skipped and only level 2 is carried out.
Saving potential due to battery preservation mode
In inverter operation the Sunny Island loads the battery by 25 W. If the device is in standby
mode, only the on-board power supply, which requires approx. 4 W, is powered. This results
in a saving of 21 W.
Using the conditions described in level 1 of the battery preservation mode for conversion
purposes and assuming an operation time from 6:00 a.m. to 10:00 p.m., this results in
336 Wh/day. This in turn corresponds to 7 Ah at 48 V and thus 210 Ah per month (30 days).
Summary of Contents for Sunny Island 4548-US
Page 2: ......
Page 14: ......
Page 240: ...www SMA Solar com SMA Solar Technology SMA America LLC www SMA America com...