SMA
Technologie AG
Battery Management
Technical Description
SI5048-11:EE4206
Page 89
Once this constant voltage phase is finished, the Sunny Island 5048 switches to float
charge which again carries out constant voltage charging but at a greatly reduced
charging voltage ("#222.10 ChrgVtgFlo" parameter). The purpose of the float charge
is to keep the battery in a fully charged state without causing premature aging through
overcharging. The Sunny Island 5048 remains in this phase until either more than 30 %
of the nominal capacity (all discharges are added together) has been used or the
charge state is less than 70 %. When the Sunny Island 5048 is operating on the public
grid, it can also switch from the float charge into silent mode (see section 13.4.5 "Silent
Mode" (Page 91)).
The charging capability of batteries is heavily dependent on the battery temperature.
For temperatures <20 °C, the charging voltage must be slightly increased, and for
temperatures >20 °C it must be slightly decreased. This is necessary to reliably prevent
overcharging and insufficient charging at all battery temperatures. For this reason, the
Sunny Island 5048 is equipped with automatic temperature compensation of the
charging voltage. The charging voltage is adjusted by 4 mV/°C and cell for battery
The charging voltage does not rapidly change, but is slowly adjusted to the new
nominal value by approx. 0.5 mV/cell*s as the constant voltage phase changes
to the float charge. This also takes place if the nominal value is changed manually.
Boost Charge
(U
0
Phase)
Full Charge
(U
0
Phase)
Equalization Charge
(U
0
Phase)
Float Charge
(U Phase)
Silent Mode
(Ruhephase)
charging processes
charging phases
Manual
3
2
2
5
4
7
6
4
4
Legend:
1: after reaching
2: after Zeit CycTmEqu (#225.05)
3: after Zeit CycTmFul (#225.04)
4: if AptTmRmg = 0 (#120.04)
5: if SOC < 70 % (#120.01)
6: only in utility, if SilentTmFlo is up (#224.02)
7: only in utility, if SilentTmMax is up (#224.03)
I-Phase
1
Summary of Contents for Sunny Island 5048
Page 22: ...The Sunny Island 5048 SMA Technologie AG Page 22 SI5048 11 EE4206 Technical Description...
Page 26: ...Safety Instructions SMA Technologie AG Page 26 SI5048 11 EE4206 Technical Description...
Page 94: ...Battery Management SMA Technologie AG Page 94 SI5048 11 EE4206 Technical Description...
Page 114: ...Connecting External Sources SMA Technologie AG Page 114 SI5048 11 EE4206 Technical Description...
Page 160: ...Contact SMA Technologie AG Page 160 SI5048 11 EE4206 Technical Description...
Page 169: ...SMA Technologie AG Glossary Technical Description SI5048 11 EE4206 Seite 169...
Page 171: ......