The National Luna Intelligent Solenoid is the brains behind adual battery management system. It manages the charging and isolation of your batteries automatically, and can be installed with no modification to your vehicle's factory wiring system.
We highly recommend adding a Dual Battery Controller to any purchase of an Intelligent Solenoid. It is an optional accessory (sold separately) that mounts to your dashboard to show the charge and storage status of your Intelligent Solenoid. The Dual Battery Controller also features an override option if an AUX battery is needed for restarting purposes.
The Intelligent Solenoid senses an incoming voltage of greater than 13.1V when you turn on the vehicle. It then starts an internal timer for 5 minutes, keeping the full charge to the primary battery to recoup for the discharge of starting the vehicle. After 5 minutes, it automatically closes the circuit in the solenoid, allowing current to flow to the secondary battery. This connection remains closed until the Intelligent Solenoid senses a voltage of less than 12.7V across the system, usually when the vehicle is shut off. The Intelligent Solenoid will keep the connection closed until less than 12.7V is available, then it will open the solenoid circuit, isolating the batteries from one another. The Intelligent Solenoid will keep the batteries isolated until it once again senses a voltage greater than 13.1V. Then it starts the timer and the whole process begins again. This process is fully automated. You do not have to manually manage the charging of the second battery.
For more information about Split Charger Systems and Installation, download the manual.