SMA SI 3324 Installation - Manual (Page 103)

SMA Technologie AG Battery Management
Installation Guide SI3324/4248-14:SE2406 Page 103
Sunny Island 3324/4248 remains in this phase until either more than 30 % of the
nominal capacity has been used (all discharges are summed) or the generator is
automatically restarted (see section 8.5 "Operation with a Generator" (Page 74)).
This means that the battery charging voltage remains below the value set under the
parameter "23-12 VchargeFloat" during this time, if (e.g.) further charging via Sunny
Boys or a public grid is possible. The purpose of the float charge is to keep the
batteries in a fully charged state without causing premature aging through
overcharging.
For the second charging level V
0
, the constant voltage charging (absorption phase)
for a limited period of time, the Sunny Island 3324/4248 automatically chooses
between three different voltages and charging times. These are the boost charge, full
charge and equalizing charge. The following figure shows a process diagram of the
charging process.
The Sunny Island 3324/4248 most often chooses the boost charge in order to bring
the batteries to a reasonable level in a short period of time. This process is optimized
to keep the generator run times as short as possible.
Boost Charge
V = VchargeBoost
Full Charge
V = VchargeFull
Equaliziation
V = VchargeEqual
Floating Charge
V = VchargeFloat
Silent Mode
Bms Silent Request = on
TcycleEquals days or 30
charging throughputs
TcycleFull days or
8 charging throughputs
V > VchargeFull
for TabsorbFull
V > VchargeEqual
for TabsorbEqual
TcycleEquals days or 16
charging throughputs