The Battery Bank Integrator (BBI) acts as a "smart" switch, connecting independent battery banks only when a charging voltage is present. Otherwise, the battery banks remain isolated, preventing discharge from one bank to another.

Traditionally, the rugged and reliable diode isolator is used for this function, as it maintains isolation between banks and allows charging from multiple sources. The drawback is inefficiency when voltage is lost as current passes through the diodes, resulting in undercharge if the charging source does not compensate for the voltage drop.

The BBI remedies this by use of a low resistance contact relay causing no voltage drop in the charging system, as the multiple batteries are automatically integrated as a single bank whenever a charging source of approximately 13.3 VDC is present.

When the alternator or charger is off, or a large load causes the voltage to drop below the disconnect point (approximately 12.7 VDC) ­ The BBI breaks the common tie between the banks. This allows selective battery discharge and prevents "dumping' of a higher-charged bank into a lower charged bank.

A solid state voltage comparator circuit with time delay prevents the BBI from cycling when the battery has voltage transients due to intermittent load demand. A 65 amp continuous duty contactor carries the current between the batteries when connected. An optional override switch may be installed to provide a "boost" for vehicle start when the auxiliary battery has a higher voltage that the main engine battery.