The REDARC BCDC Classic25, Classic40 and Classic50 are DC-to-DC chargers for auxiliary 12V batteries. They take power from the vehicle and an unregulated solar panel, prioritising available solar energy. While their exterior housings look similar, each model has its own output current and matching protection requirements. Compare the actual charger and fuse parts before planning a replacement or new installation.
Choose the correct Classic charger and fuse parts
| REDARC part | 12V charging output | Factory-recommended MIDI fuse | Product |
|---|---|---|---|
| BCDC1225D | 25A | FK40 — 40A fuse kit | classic25 |
| BCDC1240D | 40A | FK60 — 60A fuse kit | classic40 |
| BCDC1250D | 50A | FK60 — 60A fuse kit | classic50 |
| FK40 | 40A fuse service kit | For a matching Classic25 setup | fk40 |
| FK60 | 60A fuse service kit | For a matching Classic40 or Classic50 setup | fk60 |
Classic harness wire identification
| Wire or part | Manufacturer-described function | Where it connects |
|---|---|---|
| RED vehicle input | Vehicle/alternator source positive | Via appropriately sized and protected start-battery wiring |
| YELLOW solar input | Unregulated solar source positive | Solar panel array within 9–32V input limits |
| BLACK ground | Common negative return | Ground/chassis and negative returns as specified by REDARC |
| BROWN output | Positive charging output | To the auxiliary battery through its correctly sized fuse |
| BLUE trigger | Vehicle voltage/ignition operating mode | Standard mode disconnected; low-voltage trigger wiring per manual |
| ORANGE profile | Selects battery charging profile | Different connection options for lead-acid and lithium profiles |
| GREEN indicator | Optional LED and lithium-profile connection | When used with orange for the appropriate LiFePO4 charging setting |
| Battery location | Auxiliary battery near the charger | Keep cables protected; choose wire cross-section by length and current |
| Solar regulator | MPPT control built into the charger | Do not connect an external regulated solar output to the Classic solar input |
Original REDARC wiring and terminal diagrams
The factory illustrations identify the cables, fuses, terminals and charging connections for the specified model family. Open them at full size when installing or servicing equipment.
REDARC Classic 25/40/50 original battery and solar wiring diagram
Solar voltage and battery protection
The BCDC Classic solar input is designed for 12V-nominal panels with an open-circuit voltage in the manufacturer's 9–32V range. A higher-voltage household or 24V-nominal panel cannot be assumed compatible. Match the battery charge profile, fuse rating, vehicle-alternator trigger and cable gauge using the original REDARC manual. An electrically qualified installer should make the final connections.
Related RV battery-system references
See the matching chargers and accessories
Select a photo to open its NewRVParts listing. Similar-looking components may have different current limits, terminals or fitment.
BCDC1225D — REDARC Classic25 12V DC-DC Charger25A output; dual vehicle/solar inputs
BCDC1240D — REDARC Classic40 12V DC-DC Charger40A output; vehicle and solar inputs
BCDC1250D — REDARC Classic50 12V DC-DC Charger50A output; model-specific current protection
FK40 — REDARC 40A MIDI Fuse Kit40A protection recommended for Classic25
FK60 — REDARC 60A MIDI Fuse Kit60A protection recommended for Classic40/50