Renogy 12V 20A DC to DC Battery Charger
SVT Score, Lower
A 292 W, 20 A DC-DC charger for 12 V house batteries with a smart-alternator mode, an IP32 case and Bluetooth through an add-on module.
$141
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Usability
3.3 out of 10Renogy rates its output at 292 W, on the 250 to 379 W rung, so it scores 2 on capacity.
Better on capacityRenogy 40A DC-DC MPPT ChargerRenogy's manual rates it 616 W nominal output. $205.99Scores 8.0Renogy's product page states 94 percent charging efficiency, while its manual gives 94 percent when stepping voltage down and over 90 percent when boosting, so it scores 4 on efficiency.
It has a smart-alternator (Euro 6) mode that starts charging at 12 V and stops at 11.5 V with the IGN wire connected, against 13.2 V and 12.7 V in traditional mode, but the manual lists no setting for those thresholds, so it scores 8 on operating range.
Bluetooth comes only through the separately sold BT-2 module, the case is IP32, input and output share a common negative, and Renogy offers no parallel operation or solar input, so it scores 2 on features.
Better on featuresRenogy DCC30S DC-DC ChargerTakes up to 400 W of solar through MPPT. $186.99Scores 6.0No certifier directory searched (Intertek, UL Product iQ, CSA, the CEC list, LabTest, TÜV SÜD, TÜV Rheinland and SGS) lists the RBC20D1U, and Renogy's page claims only FCC and CE marks, so it scores 2 on verification.
Better on verificationRenogy DCC30S DC-DC ChargerIntertek's directory lists the RBC30D1S to UL 1741. $186.99Scores 8.0Renogy's warranty document and product page both give 2 years on materials and workmanship, so it scores 3 on warranty and support.
Renogy sets warranty terms by model, for the original buyer only, and takes unused renogy.com orders back within 30 days, lithium batteries within 7.
$140.99 at renogy.com.
Smart-Alternator ready, bluetooth costs extra
The RBC20D1U is Renogy's second-generation 12 V 20 A DC-DC charger for charging a van or RV house battery from the starter battery and alternator.
It suits a buyer with a small 12 V house battery and a smart alternator who wants app monitoring for under $170, and who will not need more than 20 A, solar input or a weatherproof mount.
Strengths
- 292 W output at 94 percent charging efficiency
- Smart-alternatorEuro 6) mode that starts at 12 V
- Under 15 mA idle draw
- Full load to 45 °C before derating
- User mode and charge current set in the DC Home app
Drawbacks
- Bluetooth needs the BT-2 modulesold separately
- IP32 casenot rated for wet or engine-bay mounting
- Start and stop voltages are fixedthe manual lists no setting for them
- Manual gives over 90 percent when boostingagainst 94 percent stepping down
- Charge current settable only to 20 A or 10 A
Specs
- CapacityNot applicable
- AC OutputNot applicable
- System Voltage12 V
- Panel PowerNot applicable
- Charge Current20-29 A
- Safety ListingNone verifiable
- Cell TypeNot applicable
- Low-Temp ChargingNot applicable
- Warranty2 Years
- MonitoringBluetooth add-on
- Weight3.3 lb
At a glance
- RS485 port for BT-2 module
- 2 m temp sensor in the box
- 3 m IGN signal wire included
- 9.31 x 5.17 x 2.30 in
Renogy is the brand of RNG International, Inc., of Ontario, California, which Dr. Yi Li founded in 2010.
It sells direct from renogy.com and its Amazon and eBay brand stores, and through Home Depot, Lowe's, Best Buy, Camping World and Walmart's marketplace.
The Renogy RBC20D1U (RBC20D1U-G1 in its manual) is a second-generation 12 V to 12 V buck-boost DC-DC charger rated 20 A and 292 W of output, 300 W maximum input, with 94 percent charging efficiency by Renogy's product page. It takes 12 to 16 V from a smart (Euro 6) alternator or 13.2 to 16 V from a traditional one: in traditional mode it starts charging when the starter battery holds 13.2 V for 15 seconds and stops at 12.7 V, and with the IGN signal wire connected for a smart alternator it starts at 12 V and stops at 11.5 V. It charges sealed, AGM, gel, flooded and lithium iron phosphate batteries, plus a user mode set in the DC Home app, can wake a lithium battery that has gone to sleep, and draws under 15 mA at idle. It runs at full load to 45 °C (113 °F), then loses 5 A for every 2 °C until it stops at 60 °C (140 °F). The case is rated IP32, cooled naturally, measures 9.31 x 5.17 x 2.30 in (236.5 x 131.5 x 58 mm) and weighs 3.3 lb, with an RS485 port for Renogy's BT-2 Bluetooth module. The box holds the charger, a 2 m battery temperature sensor, a 3 m IGN signal wire, four ST4 x 16 mm mounting screws and the quick guide; Renogy's page also lists four terminal rings. Renogy sells it alone at $140.99 and with the BT-2 module at $168.99.
Questions answered from our data
Is Renogy good?We list 58 Renogy products and score 58 of them. Their overall scores run from 3.7 to 6.6, with a median of 5.4, against a median of 5.4 for all 58 products we score.
How much does a DC-DC charger cost?The 7 dc dc chargers we list run from $141 to $410, with a median of $206.
Are DC-DC chargers UL listed?Two of the 7 dc dc chargers we list carry a UL 458-type listing we could look up by model.- Which DC-DC chargers have Bluetooth?Five of the 7 dc dc chargers we list offer Bluetooth monitoring, built in or as the maker's add-on.
