Description
The KISAE BDC4825 is a fully automatic bi-directional DC-DC battery charger purpose-built for 48V house battery systems in RVs, boats, vans, and off-grid installations. Accepting input from both a 12V or 24V vehicle alternator and a solar array up to 100V VOC, the BDC4825 keeps your 48V house battery bank charged from every available power source without the need for external relays or additional controllers. Whether you’re on the road, on the water, or miles from the grid, the BDC4825 has you covered.
The built-in MPPT solar controller delivers greater than 98% tracking efficiency, extracting maximum power from your solar array across the full 15V–100V VOC input range. When alternator input is available, the BDC4825 draws up to 25 amps from a 24V alternator system or up to 12.5 amps from a 12V system to efficiently charge the house battery bank through its microprocessor-controlled multi-stage charging algorithm, covering Bulk, Absorption, Float, and Recharge stages for GEL, AGM, Flooded, Lithium, and Programmable battery types. Five configurable priority modes let you define exactly how solar and alternator inputs work together, and the smart charging feature automatically regulates output based on connected DC loads to prevent unnecessary cycling and protect battery health.
The BDC4825 also brings a capability rarely found in DC-DC chargers: bi-directional reverse charging. When your alternator or starter battery runs low, simply activate the reverse charge port and the house battery becomes the DC source, delivering 13.5V at up to 25A to a 12V alternator system or 27V at up to 25A to a 24V system, getting you back up and running without needing a jump start. The included backlit LCD remote display monitors house battery voltage, charging current, and charging status in real time, while the CAN BUS communication port allows integration with compatible vehicle and marine control networks.
-
DC Output Specifications Output current with 12 V alternator input Maximum 12.5 A Output current with 24 V alternator input Maximum 25.0 A Output current with solar input Maximum 25.0 A Charge voltage range 54 – 60V Float voltage range 48 – 54V Equalize voltage 62V Charge control 5 stages (test/bulk/absorption/float/recharge) Battery type Gel, Flooded (with Equalization), AGM, Lithium, Program Efficiency > 90% DC Input (Starter Battery/Alternator) Specifications Range 10.5 – 32 VDC Start up voltage with 12 V system (user selectable) 11.5 – 13.8 V Start up voltage with 24 V system (user selectable) 23.0 – 27.6 V Max input current 80 A DC Input (PV) Specifications Max PV open circuits voltage 100 VDC (VOC) Max input current 80 A Start up voltage 21.5 VDC Nominal operation 15 – 80 VDC MPPT tracking efficiency > 98% Reverse Charging Specifications 12 V alternator system Constant 13.5 V @ 25 A 24 V alternator system Constant 27.0 V @ 25 A General Specifications Dimensions 14.0 × 8.1 × 3.8 in (356 x 205 x 97 mm) Inverter weight 7.1 lbs (3.2 kg) Shipping weight 10.0 lbs (4.5 kg) Warranty 2 years - See spec sheet for additional info
