SUNNY ISLAND 5048 - Technical Description - Wind & Sun Ltd.

Battery Management SMA Solar Technology AG
Parallel procedures for full charge
Any parallel procedures causing the generator to stop during the full charging process are
not taken into account until the charging process is completed.
13.4.3 Equalization Charge
A battery bank consists of many individual battery cells connected in series which all behave slightly
different. Over time, this results in different charge levels in the individual cells. This can lead to
premature failure, initially of individual cells, and finally to failure of the entire bank.
The Sunny Island can perform an equalization charge automatically every 180 days
("222.06 CycTmEqu" parameter) or every 30 nominal charge throughputs. During this process, it
performs controlled overcharging of the battery bank to ensure that even the weaker cells are fully
recharged. Equalization charging extends the battery service life by up to 50 %. The automatic
equalization charging function can also be deactivated ("222.12 AutoEquChrgEna" parameter,
activated by default) or manually started ("520.01 ChrgSelMan" parameter).
Change to an equalization charge
If the Sunny Island changes to equalization charge after a specific time of boost charging
or full charging has elapsed, these times are completely considered for the equalization
charge.
More than 1 % of the nominal battery capacity is discharged
If more than 1 % of the battery's nominal capacity is discharged during an equalization
charge, 50 % of the time elapsed is considered for the next constant voltage phase.
External charging device
If an external charger or charge controller is connected to the battery and the criteria for
an equalization charge are fulfilled due to external charging, the Sunny Island treats this
as if it had performed the equalization charge itself.
102 SI5048-TB-TEN110340 Technical Description