Boost Charge; Full Charge; Equalization Charge - SMA Sunny Island 5048 Installation Instructions Manual

Battery Management
types VLA and FRLA as well as by 0 mV/°C and cell with NiCd batteries. The
temperature compensation value can be set using the "#222.11 BatTmpCps"
parameter.

13.4.1 Boost Charge

The boost charge is the most common charging process of the Sunny Island 5048. The
boost charge ensures a high generator capacity through a high charging voltage over
a short period of time. With liquid FLA lead acid batteries, this charge process should
be used for gassing and thus compensating the electrolytes. The boost charge process
can charge the battery between approx. 85 % and 90 %.

13.4.2 Full Charge

The Sunny Island 5048 initiates a full charge every 14 days ("#222.05 CycTmFul"
parameter) or every eight nominal charging throughputs. The objective is to charge the
battery to a charge state of at least 95 % and remove any negative effects caused by
insufficient charging. Regular full charging approximately every 2 — 4 weeks doubles
the service life of the battery.
If, after a specific time of boost charging has elapsed, the Sunny Island 5048
switches to a full charge, the entire elapsed time of boost charging is taken into
consideration during the full charge.
If, during a full charge, more than 1 % of the nominal battery capacity is
discharged, then 50 % of the elapsed time is taken into consideration during the
next constant voltage phase.
If an external charging device or a charge control is connected to the battery and
the criteria for a full charge are satisfied by the external charge, then the Sunny
Island 5048 treats this as if it had performed the full charge itself.

13.4.3 Equalization Charge

A battery bank consists of many individual series-connected battery cells which all
behave slightly differently. 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 5048 can automatically perform an equalization charge every 180
days ("#222.06 CycTmEqu" parameter) or every 30 nominal charging 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 switched off, if desired, ("#222.12 AutoEquChrgEna" parameter, activated by
default) or manually started ("#420.01 ManChrgSel" parameter).
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Technical Description