Use Victron Energy’s Buck-Boost DC-DC Converter for charging a 12V or 24V service battery in vehicles with a smart alternator. The converter will charge the auxiliary battery with a pre-set charge voltage, eliminating high voltages (e.g. Mercedes: 15,4V) and low voltages.
The DC-DC converter’s built-in ‘engine running’ detection system acts to prevent deep discharge of the vehicle’s starting battery. The converter can also be activated by means of a programmable input (D+, CAN bus or (+)15 connection).