SMA SI 3324 Installation - Manual (Page 106)

Battery Management SMA Technologie AG
Page 106 SI3324/4248-14:SE2406 Installation Guide
The following figure shows the four battery states:
For deep discharge protection the Sunny Island 3324/4248 monitors both the
voltage, the battery current and the time, allowing it to recognize deep discharge
and also avoid false alarms and shutdowns.
As long as the Sunny Island 3324/4248 has not detected a deep discharge then it
is in the battery state (BatState) Normal.
As soon as the first level of deep discharge is reached, the Sunny Island 3324/4248
switches to the Warning state. This can be used to start a generator.
If the batteries are further discharged despite the warning, then the battery state now
jumps to the next deep discharge level Low. If desired, this level can be used to
trigger the Sunny Island 3324/4248 relay contact to switch off all or some of the
loads ("40-6 LoadShedding" parameter set to "On"; see section 8.6 "Automatic Load
Shedding Setting" (Page 80)).
If this is not done and the batteries are still further discharged then the battery state
reaches the last level Critical.
If no charging current flows into the batteries within five minutes of entering this state,
then the Sunny Island 3324/4248 automatically switches to standby mode to avoid
any further deep discharge.
Normal
Warning
(Start
Generator)
Low
(Load
Shedding)
Critical
(Shut
down)
BatVoltage, BatCurrent >
SocLim1
for t > 15 minutes
BatVoltage, BatCurrent >
SocLim2
for t > 15 minutes
BatVoltage, BatCurrent >
SocLim3
for t > 15 minutes
or charge current
BatVoltage, BatCurrent <
SocLim1
for t > 2/6/30 minutes
BatVoltage, BatCurrent <
SocLim1
for t > 2/6/30 minutes
and no charging current
BatVoltage, BatCurrent <
SocLim2 for t > 2/6/30
minutes
100 %
SocLim1
SocLim2
SocLim3
0 %