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40A DC-DC Battery Charger with MPPT

SKU: RBC40D1S-US
$205.99
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Key Features
  • Two charging options to ensure ultimate efficiency.
  • Supports LiFePO4, Gel, Flooded, and Sealed Lead Acid..
  • Comprehensive protections to safeguard the system.
  • Features lights and buttons for easy use and error alerts.
  • Complies with FCC, RoHS, CE, SAA; includes 2-year warranty.
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30-Day Return and Refund Service
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Delivery time: 1-3 business days.Shipping Policy
Description
Includes
Specs
Downloads
FAQ
Reviews

Renogy 12V 40A DC to DC Battery Charger with MPPT

This sleek, versatile charger keeps you powered wherever you go. It switches seamlessly from DC input while driving to solar charging when parked. With a simple press of the SELECT button, you can easily set solar priority mode for maximum efficiency.

Effortlessly switch between solar and DC inputs to keep your battery charged efficiently, all while enjoying the reliability and superior performance you expect.

Seamlessly Mode Switch

The system automatically switches to the alternate charging mode when the input voltage in the primary mode drops below the default threshold, ensuring continuous, efficient charging.

DC Priority
Solar Priority

Understand the Charging Logic Behind Each Model

The 30A and 50A models support dual input from solar and alternator simultaneously, offering maximum flexibility and faster charging. The 40A model intelligently switches between inputs based on availability—the most cost-effective solution on the road.

Get to Know the Key Points

Select the most suitable charger tailored to your system requirements.

RV
SUV
Boat

Stay Charged on the Move

Stay Charged on the Drive

Stay Charged on the Water

Multiple Safety Certifications

Achieving peak standards for reliable off-grid power

Wiring Diagram

Effortless installation with pre-installed wires and clear labels

Get the Proper Specs for Your System

For longer cable runs, use a larger gauge to minimize voltage drop, reduce power loss, and safeguard your batteries, ensuring efficient and reliable power transfer.

Recommended Accessories

Complete your setup with all the essential accessories from Renogy for a seamless, one-stop shopping experience.

This cable ensures a reliable and efficient connection between your solar panels and charger.

This cable maximizes efficiency, easily delivering power from your charger to your battery.

Safeguarding your system from overloads and maintaining peak performance.

Package Includes

Battery Charger

x 1

Heat-shrink tubings

x 7

Mounting Screws

x 4

Renogy 40A DC-DC Battery Charger with MPPT

General Data

Model
RBC40D1S
Grounding
Common Negative
Operating Temperature
-4℉ -113℉ /-20 ℃ - 45℃
Storage Temperature
-4℉ -140℉ /-20 ℃ - 60℃
Humidity
0%~90% RH
Cooling
Heat Sink
Enclosure Rating
IP31
Dimensions (LxWxH)
195 x 149 x 48 mm / 7.68 x 5.87 x 1.89 inch
Weight
1.2 kg /2.65 lb
Regulatory and Safety Specifications
FCC Path 15, Class B,CE,RoHS，SAA

Charging Data

System Voltage
12V-12V
Maximum Output Current Rating
40A
Solar Input Voltage
10 -30V DC
Output Voltage
10 -16V DC
Alternator Input
Traditional Alternator: 13.2-16.0VDC; Smart Alternator (Euro 6): 12-16.0VDC
Output Power
616W
Battery Types
AGM, Gel, Flooded, Lithium-iron Phosphate
Input Fuse Rating
60A
Output Fuse Rating
50A
Charging Efficiency
93%
Idle Power Consumption
＜10 mA

Warranty Information

Accessories
2-year material and workmanship warranty

Resources Download

Manual

Download

Quick Guide

Download

Warranty

Download

Frequently Asked Questions

What type of alternator is this DC to DC on board battery charger compatible with?

This battery charger is designed to work with both conventional and smart alternators. However, because conventional alternators maintain a consistent voltage during charging, while smart alternators adjust their charging output based on operating conditions, it is necessary to connect the charger to the smart alternator using the IGN cable (ACC labeled) from the product through the Vehicle Ignition Port.

What types of battery does the charger support?

It's suitable for 12V Lithium, Gel, AGM, and Calcium batteries. This charger enables the batteries to reach a full 100% charge. Additionally, it has the capability to revive lithium batteries that have become discharged to a low voltage.

How do l set the battery since there is no display screen?

To change the battery type, press and hold the SELECT button on the side of the battery charger. The LED lights corresponding to each battery type will illuminate in sequence, indicating the available options.

If both solar power and the engine are available, can we prioritize using solar power to charge the battery?

Our product defaults to DC charging. To prioritize solar charging, simply press the SELECT button on the side.

Can solar charging and DC charging be switched automatically?

Solar and DC charging will automatically switch based on the following conditions: 1) When the generator is running, the system will switch from DC to solar charging if DC input voltage is <11.3V and solar input voltage is >13V. 2) When the generator is off, it will switch to solar charging if DC input voltage is <12.7V and solar input voltage is >13V.

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