Victron Energy Buck-Boost DC-DC Converter is a DC-DC Converter for charging a 12V or 24V service battery in vehicles with a smart alternator Victron Energy Buck-Boost DC-DC Converter is the solution for battery charging problems with Euro 5 and Euro 6 engines and alternator charge current protection with lithium systems Engine running detection system: Deep discharge of the vehicle's starting battery is avoided by a built-in engine running detection system Fully programmable: The converter can be fully programmed by means of a simple and user-friendly PC application One product for 12V, 24V and 12/24V systems: The converter can be programmed to charge a 12V or a 24V auxiliary battery from either a 12V or a 24V alternator and starter battery Victron Energy Buck-Boost DC-DC Converter 100 Amp for Charging a 12V or 24V Service Battery in Vehicles with an intelligent dynamo. Since, when the engine is running, these dynamos (powered by the on-board electronics of Euro 5 and 6 engines) do not always emit the correct charging current, a DC-DC converter is essential for charging the service battery properly. Victron Energy Buck-Boost DC-DC Converter is the solution for battery charging problems with Euro 5 and Euro 6 engines and alternator charge current protection with lithium systems.