The Digital Echo Charge detects when the house battery bank is being charged and directs a portion of the charge current to auxiliary or starting batteries. Conveniently control the charging of auxiliary or starter batteries from an inverter/charger or other source without overcharging. Automatically switches On/Off to charge a starter battery without affecting the main battery bank. Can be used for 12V or 24V systems. Minimal insertion loss. Straightforward three wire installation. Key Features Utilizes excess current from the primary charging sourceCharges auxiliary or starting batteries from inverter/charger with limited voltage drop Automatically switches on and off without affecting the battery bank or overcharging Automatically adjusts for 12 or 24V(both battery banks must be the same DC voltage and battery type) Maximum Output:15A max. charging current Dimensions:5"H x 4.5"W x 1.25"D Safety Features:Thermal, over current, reverse polarity protection Warranty:One yearOwner's ManualData Sheet