The Smart BatteryProtect disconnects the battery from non-essential loads before it is completely discharged (which would damage the battery) or before it has insufficient power left to crank the engine.

When using Bluetooth to program the Smart BatteryProtect any required engage/disengage levels can be set.
Alternatively, one of nine predefined engage/disengage levels can be set with the programming pin (see manual). 

If required, Bluetooth can be disabled.

The Smart BatteryProtect is not designed for reverse currents from charging sources.