Battery deep discharge protection

On SMA battery inverters, event 9394 is logged when the battery management system turns on deep discharge protection. For grid-connected systems this message is only an event and not a warning. A related battery fault message means the battery has reached either the deep discharge protection area or the deep discharge area, and a fuse at the grid-connection point may have tripped. Inside the deep discharge protection range, the system switches to energy-saving mode and tries to recharge the battery automatically from available PV energy. The protection ranges are set as a percentage of battery capacity, and the allowed limits differ between lead-acid and lithium-ion batteries. Check first whether a fuse has tripped at the grid-connection point and whether PV energy is available to recharge the battery. Then review the deep discharge range settings for the battery type.

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• sentence 6: support check: partial - The fuse and PV recharge facts appear, but the passages give no troubleshooting order or instruction to check them or review settings by battery type. -->