SMA Sunny Island 4248U, Инструкция по установке и эксплуатации

Страница: 70 / 100

Battery Management SI4248U Manual
62
Generator, Load Shedding Control and Battery State of Charge
State of Charge
Generator start and load shedding are controlled by the State of Charge (derived from current
compensated battery voltage). The generator control also considers the battery size.
Generator and Load Shedding Control distinguishes between four states (see Battery Meters
BatState and figure below):
• Normal
• Start Generator
• Start Load shedding (includes Start Generator)
• Critical Battery State (Shut down)
The transitions between these states are controlled by the State of Charge calculated from the
battery voltage and a timer (see "
State transition for generator start and load shedding
" on page 63).
The mentioned time of 2 minutes is active when Sunny Island 4248U sees discharging. The 30
minutes time is active for charging or for discharging with currents less than 0.5 A per 100 Ah
battery capacity. The 6 minutes time is active with charging currents of 0.5 to 2 A per 100 Ah
capacity. The 30 minutes time is active with charging current above 2 A per 100 Ah.
Figure 1-26 Generator Start Delay vs. Normalized Battery Current
-5
Battery Current [A/Ah]
Gener
at
or S
tar
t Dela
y [min]
0
5
10
15
20
25
30
-4 -2 -3 -1 0 2 1 3 4 5
30 min
6 min
2 min
Charging
Discharging