Renogy DCC30S 30A DC-DC MPPT
#2 in DC-DCFull review
For smaller vans and truck campers with a 100 Ah battery and a panel or two on the roof. Bigger banks or arrays need the 50 A DCC50S.
Amazon $186.97$186.97
3.8/5
A cheap, quiet way to add alternator charging to a van or camper with a lithium house battery. Pay more for Victron if you want built-in Bluetooth.
- 40 ACharge current
- 12 VBattery
- 94%Efficiency
- 2 yearsWarranty
Check price at Amazon$177.64
Price checked October 22, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Recharges a 100 Ah lithium battery from flat in roughly 2.5 hours of driving
- Works with smart alternators; the ignition wire and a battery temperature sensor are in the box
- Fan-free, so it runs silently
- User mode lets you set your own charge voltages
Cons
- No built-in Bluetooth; the app needs the BT-2 module, sold separately
- No solar input
- Not isolated: input and output share a common negative
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its type. How we rank explains each one.
Specifications
| Model number | RBC40D1U |
|---|---|
| Charging | |
| Type | DC-DC charger |
| Charge current | 40 A |
| Battery voltage | 12 V |
| Lithium profile | Yes |
| Custom profile | Yes |
| Temperature sensor | Included |
| Peak efficiency | 94% |
| Standby draw | 15 mA |
| Inputs | |
| DC input range | 12 to 16 V |
| Isolated | No |
| Smart alternator | Yes |
| Ignition sensing | Yes |
| Monitoring and build | |
| Bluetooth | Optional add-on |
| Display | No |
| Load output | No |
| Cooling | passive (fan-free) |
| Dimensions | 9.31 x 6.00 x 2.30 in |
| Weight | 4.1 lb |
| Warranty | 2 years |
Alternatives in this type
Renogy DCC50S 50A DC-DC MPPT
#3 in DC-DCFull review
The value pick for vans and campers that want alternator and solar charging in one box. It costs well under half as much as a Redarc dual-input unit for more current.
Amazon $268.99$268.99
Victron Orion-Tr Smart 12/12-30
#5 in DC-DCFull review
For boats and vans that need an isolated charger from a brand with a long track record. Buyers who don’t need isolation get more current and efficiency from the Orion XS.
Amazon Northern Arizona Wind & Sun $219.30$219.30
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