The Smart BatteryProtect disconnects the battery from non-essential loads before it is completely discharged (which could damage the battery) or before there is insufficient charge left in the battery to crank the engine. When using Bluetooth to program the Smart BatteryProtect, you can set any required battery engagement/disengagement levels. Alternatively, using the programming pin, one of nine predefined battery engagement/disengagement levels can be set (refer to the manual).