Compact, intelligent 12 V DC-to-DC battery charger with Bluetooth for automatic multi-stage charging of a second battery bank.

• Bluetooth connectivity: inbuilt Bluetooth allows monitoring and parameter changes via the VictronConnect app without accessing the installation location.
• Function: automatically charges one 12 V battery/battery bank from another 12 V battery/bank (e.g. alternator‑topped starter to leisure battery) at up to 30 A using intelligent multi‑stage charging with full overcharge protection.
• Safe unattended charging: inbuilt safety functions including protection against overload, overtemperature, short‑circuit and reverse polarity for reliable unattended operation.
• Continued charging during battery/load use: the charger will continue to operate at full power whilst energy is drawn from the target battery or load.
• Compatibility with other charging sources: thanks to the inbuilt suppression filter, batteries may be charged from alternator, solar or mains sources without interference to the charger or vehicle electronics.
• Remote on/off control: can be controlled by a hard‑wired switch, external relay or via the VictronConnect app for flexible installation and operation.
• Vehicle battery optimisation & system upgrade potential: designed for efficient vehicle battery charging and may be connected in parallel with identical units to boost output for future system expansion.
• Additional features and compatibility: LED indicators for charging stage/status; suitable for use with any 12 V lead acid or lithium battery. Input voltage: 8–17 V. Output current: 0–30 A. Output voltage adjustable: 10–15 V (12.2 V nominal); tolerance ±0.2 V.
• Technical & installation details: Output noise 2 mV RMS. Max power 430 W. Under voltage shutdown 7 V; under voltage restart 7.5 V. Standby consumption < 1 mA. Temperature range -20 to +55 °C (-4 to +131 °F). Ambient humidity max. 95% non‑condensing. Max cable cross section 16 mm² (AWG6). Dimensions 130 x 186 x 80 mm (5.12 x 7.32 x 3.15 in). Weight 1.8 kg (3.97 lb).

Downloads: user manual for 30 A 12 V DC‑to‑DC battery charger (VOS1212‑30NI) and product datasheet available. Check compatibility with your charging sources and battery chemistry before installation.