SUNNY ISLAND 5048 - Technical Description - Wind & Sun Ltd.
SUNNY ISLAND 5048 - Technical Description - Wind & Sun Ltd.
SUNNY ISLAND 5048 - Technical Description - Wind & Sun Ltd.
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SMA Solar Technology AG Battery Management<br />
The charging capability of batteries is highly dependent on the battery temperature. For temperatures<br />
< 20 °C, the charging voltage must be slightly increased, and for temperatures > 20 °C, it must be<br />
slightly decreased. This is necessary to prevent overcharging and insufficient charging reliably at any<br />
battery temperature. For this reason, the <strong>Sun</strong>ny Island is equipped with automatic temperature<br />
compensation of the charging voltage. The battery charging voltage is adjusted by:<br />
• 4 mV/°C and cell, in the case of VLA and FRLA battery types<br />
• 0 mV/°C and cell, in the case of NiCd batteries<br />
The temperature compensation value can be set using the parameter "222.11 BatTmpCps".<br />
13.4.1 Boost Charge<br />
The boost charge is the most common charging process of the <strong>Sun</strong>ny Island. The boost charge ensures<br />
a high generator workload through a high charging voltage over a short period of time. With liquid<br />
FLA lead acid batteries, this charge process should be used for gassing and thus compensating the<br />
electrolytes. The boost charge process can charge the battery up to approx. 85 % to 90 %.<br />
13.4.2 Full Charge<br />
Every 14 days or 8 nominal charge throughputs, the <strong>Sun</strong>ny Island automatically initiates a full charge<br />
(parameter "222.05 CycTmFul").<br />
Nominal charge throughput<br />
A nominal charge throughput is reached when the sum of the discharge currents<br />
corresponds to the nominal capacity of the battery.<br />
Example: The battery has a nominal capacity of 100 Ah. A nominal charge throughput is<br />
reached when the battery has been discharged 10 times for 1 hour by 10 A.<br />
The objective is to recharge the battery to a state of charge of at least 95 % and rectify possible effects<br />
caused by an insufficient charge. Regular full charging approximately every 2 to 4 weeks can double<br />
the service life of the battery.<br />
Change to a full charge<br />
If the <strong>Sun</strong>ny Island changes to full charge after a specific time of boost charging has<br />
elapsed, the entire time of boost charge elapsed is considered for the full charge.<br />
More than 1% of the nominal battery capacity is discharged<br />
If more than 1 % of the battery's nominal capacity is discharged during a full charge, 50 %<br />
of the time elapsed is considered for the next constant voltage phase.<br />
External charging device<br />
If an external charging device or charge controller is connected to the battery and the<br />
criteria for a full charge are fulfilled due to external charging, the <strong>Sun</strong>ny Island treats this<br />
as if it had performed the full charge itself.<br />
<strong>Technical</strong> <strong>Description</strong> SI<strong>5048</strong>-TB-TEN110340 101