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BATTERY PROTECTION DESCRIPTION
Battery will act a protective charge/discharge current limitation under any condition
as below:
•
Battery SOC is lower than 1-DOD.
•
Battery voltage lower than discharge voltage.
•
Battery over temperature protection.
•
Battery communication abnormal for lithium battery.
•
BMS limitation for lithium battery When charge/discharge current limitation
protection.
•
Under on-grid mode, battery charge/discharge operation could be abnormal
Under off-grid mode, Back-Up supply will shut down.
•
NOTE:
•
Under on-grid mode, battery is protected from over discharge by DOD and
discharge voltage, under off-grid mode, it is protected by only discharge voltage
and DOD.
•
The DOD setting of a battery prevents the inverter from discharging battery
reserve power. As soon as the DOD is reached the load of building will only be
supported by either PV power or from the grid. If there are continuous days when
little or no battery charging occurs, the battery may continue to self-consume
energy to support communications with the inverter. This behavior is different
between battery manufactures products, however, if the SOC of the battery reaches
a certain level the inverter will boost the SOC back up. This protection mechanism
safeguards the battery to falling to 0 SOC.
2.4.2ON-GRID & BACK-UP CONNECTION
An external AC switch (
≥
40A for SPA 3.68H,
≥
50A for SPA5.0H) is needed for
On-Grid and Back-Up connection to isolate from grid when necessary. Below
are the requirements on AC switch use.
Note:
The absence of AC breaker on Back-Up side will lead to inverter damage
if only electrical short-circuit happened on Back-Up side.
