SMA Sunny Island 4248U, Инструкция по установке и эксплуатации

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Battery Management SI4248U Manual
64
How to set up State of Charge Limits
NOTE: This process applies to FLA type batteries with accessible cells only. For
sealed batteries, please refer to the manufacturer’s guidelines for acid density
values.
The 3 limits for generator start, load shedding and shut down, can be set as State of Charge
(SOC) values (SocLim1, SocLim2, SocLim3). The battery management assumes the acid density
to 1.28 kg/l. If the Acid Density of the used battery is different, user must adapt the desired
SOC value.
Figure 1-28 State of Charge and Open Circuit Voltage Levels depending on Acid
Example:
If the generator should start at a SOC of 40% or when the battery has a specific gravity of 1.24
kg/l, then:
The SocLim1 should be set to 25%. To determine this value, begin at 40% SOC, go up to the
blue curve (which represents 1,24 kg/l), go left to meet the red line, go down and find 25%.
The firmware always assigns the SOC parameter with the highest value to SocLim1 (generator
start) and the lowest to SocLim3 (shutdown) and the remaining value to SocLim2 (load
shedding) to ensure reasonable order of SOC thresholds.
If the generator is started by the Sunny Island 4248U due to reaching a voltage level
corresponding to SocLim1 State of Charge, it will run until the charge operation has completed,
(i.e. completion of the absorption phase and then switching to float). If the generator starts
during Float, (e.g. with DC-loads only), the BMS will automatically switch to boost charge and