REDARC BCDCN1240 BCDC Core 40A in-cabin DC-DC charger12V 40A in-cabin DC-DC charger with MPPT solar input

Overview

The BCDCN1240, or BCDC Core 40, is the 40A, 600W version of REDARC's in-cabin dual input charger, with a 55A maximum current rating. REDARC suggests it for lead-acid banks over 200Ah and lithium batteries over 100Ah where the battery accepts 40A. Alternator and unregulated solar inputs of 9–32V are used together, solar first, and the low-voltage trigger supports smart alternators. Mount it in the cabin, canopy or a battery box within 1m of the auxiliary battery and fuse input and output at 60A.

• 25A or 40A output to a 12V auxiliary battery
• Vehicle and solar inputs 9–32V with MPPT regulator
• Solar used first, alternator tops up
• Profiles A, B, Li and heated-lithium H
• For cabin, canopy or battery box, not the engine bay
• 900g, 165×120×37mm, no fan

How it works

The BCDC Core is a three-stage DC-DC charger for a 12V auxiliary battery that draws power from a 12V or 24V start battery and from unregulated 12V solar panels. Its MPPT regulator and Green Power Priority logic use all available solar first and add alternator power up to the rated output. Because input voltage is compensated, the auxiliary battery receives the correct charge voltage despite long cable runs from the front of the vehicle.

An internal voltage-based isolator separates the auxiliary system from the start battery: with the standard trigger the charger turns on above 12.9V and off below 12.7V (25.8V and 25.4V in 24V vehicles). Charging runs through boost, absorption and float, with float held at 13.3V for lead-acid and 13.6V for LiFePO4.

Key features

The orange wire selects one of four profiles: A (14.6V) for AGM and gel, B (15.0V) for standard lead-acid and calcium, Li (14.2V) for LiFePO4 and H (14.2V) for lithium batteries with a working heating element, which allows charging down to -20°C. The plain Li profile charges between 0°C and +80°C. Compliance marks include E-mark UNECE R10, CE, UKCA, RCM and RoHS. The housing has no fan or relays, so the charger runs silently.

Installation and compatibility

The Core must not be fitted in the engine bay: moisture and heat can damage it. Install it in the cabin, a ute canopy, a caravan or a battery box, within 1m of cable from the auxiliary battery, using M6 fasteners and leaving ventilation space. Output derates above 55°C and the unit stops at 80°C. Fuse both the vehicle input and the output within 100mm of the battery: 40A (FK40) for the 25A model and 60A (FK60) for the 40A model.

Vehicles with smart or variable-voltage alternators, common on Euro 6 vehicles from 2015 onwards, need the blue wire connected to D+ or ignition for the low-voltage trigger (on at 12.0V). Solar panels must be unregulated and connected in parallel; open-circuit voltage must not exceed 32V.

Status and protection

Profile and charge-status LEDs show the active profile, which inputs are delivering power and the charge stage, and an optional 12V LED can be added. Fault codes are flashed for internal faults, temperature limits, high output voltage and input under- or over-voltage. The vehicle input shuts down instantly below 8.0V or above 16.0V (32.5V for 24V systems), and a periodic test checks the start battery voltage and that an output battery is present.

Questions and answers