Sterling Power
Sterling Power BB1224120 – 12V/24V to 24V DC-DC Battery Charger
Choose options
The Sterling Power BB1224120 is a cross-voltage battery-to-battery (DC-DC) charger that takes a 12V or 24V input and charges a 24V auxiliary bank, delivering up to 58A at 28.4V. It's built for 24V house systems in campers, marine, and expedition builds running from a 12V or 24V vehicle electrical system.
Unlike a voltage-sensitive relay, the Saturn charger measures both current and voltage to move intelligently through bulk, absorption, and float, giving your batteries a correct, complete charge on every drive. Six preset profiles (Lead, AGM, and Lithium — two of each) plus custom profiles via the optional BBR remote suit virtually any chemistry.
Charging Specifications
| Type | 12V / 24V → 24V battery-to-battery (DC-DC) charger, Saturn series |
|---|---|
| Input voltage range | 9–16V (12V) / 18–32V (24V) |
| Max output current | 58A at 28.4V |
| Max output power | ~1,540W |
| Max input current | 120A (12V) / 60A (24V) |
| Efficiency | 95–98% |
| Reverse / jump-start current | Up to 50A (12V) / 25A (24V) |
| Battery profiles | Lead I/II, AGM I/II, Lithium I/II (6 presets) + custom via BBR remote |
| Temperature sensor | TEMP1 included |
| Cooling | Thermostatically controlled, variable-speed fan |
| Protections | Self-recovering: under-voltage, input & output over-voltage, over-current, over-temperature |
| Recommended input cable / fuse | 35mm² (2AWG) / 150A |
| Recommended output cable / fuse | 16mm² (6AWG) / 80A |
| Dimensions | 270 × 130 × 73 mm |
| Weight | 1.8 kg |
| Operating temperature | −20°C to 60°C |
| Certifications | CE, UKCA |
| Warranty | 5-year return-to-factory |
Key Features
- Charges a 24V bank from a 12V or 24V vehicle system — up to 58A at 28.4V
- Bidirectional reverse-charge (jump-start assist) of up to 50A (12V) / 25A (24V)
- Six battery profiles plus custom charge profiles via the optional BBR remote
- Lithium-safe: a live output wakes most BMS units; charging is disabled below 0°C when the temp sensor is fitted
- Self-recovering protections and conformal-coated internals; CE/UKCA approved; 5-year warranty
Smart Alternator / Euro-6 Ready
Three engagement modes cover any vehicle: automatic voltage sense, ignition-feed control (for smart/Euro-6 alternators), and vibration sense (begins charging after detecting engine vibration — no ignition wire required).
Installation Notes
Requires a common, direct negative between the input battery, charger, and output bank. The positive input must come from a circuit with a starter battery or Alternator Linearisation Device — not straight off a bare alternator. Fuse both input and output; recommended input cable is 35mm² (2AWG) with 150A fusing and output cable 16mm² (6AWG) with 80A fusing for runs under 3m.
Presented by Overland Kitted
The Dispatch
Gear We Like: DVA Mechanics for the Grenadier
MAXTRAX Introduces Universal Mounting Pins for MKII, XTREME, and LITE Boards
