Dual-input DC-DC battery charger that charges an auxiliary battery from the vehicle's alternator and solar simultaneously, with built-in Green Power Priority to reduce alternator load. Suitable for engine bay installation.
The Redarc BCDC1240D, part of Redarc's BCDC Classic40 lineup, is a 40A dual-input DC-DC battery charger designed to keep an auxiliary battery charged whether driving or parked with solar panels connected. Its built-in Maximum Power Point Tracking (MPPT) solar regulator allows the unit to charge from the alternator and solar at the same time, with Green Power Priority giving preference to solar input first to reduce load on the alternator.
The charger works across a wide 9-32V DC input range, supporting both 12V and 24V vehicle systems, and is compatible with standard or variable/smart alternators. It uses multi-stage DC-DC charging with patented charging profiles for different battery chemistries, including a dedicated lithium profile, and also functions as a dual battery isolator, protecting the vehicle's start battery if voltage drops too low. The unit is fully sealed, fan-free for quiet operation, and rated to withstand extreme heat and deep water crossings.
The BCDC1240D is designed for battery bank sizes of roughly 200AH and above in most applications. For smaller battery banks in the 75-200AH range, Redarc recommends the BCDC1225D (25A) instead.
Professional installation by a qualified auto electrician or technician is recommended, particularly for the alternator, solar, and battery wiring connections. The unit can be mounted in various locations including the engine bay, but should be positioned away from high heat sources and with sufficient ventilation for cooling. Redarc offers vehicle-specific mounting brackets for some common platforms.
• (1) Redarc BCDC1240D BCDC Classic40 charger • Wiring loom and connectors • Mounting hardware • User manual
Covered by Redarc's 2-Year Warranty.