Renogy DC-DC Battery Charger

Before Getting Started

This quick guide provides important operation and maintenance instructions for the Renogy 12V 20A/40A DC-DC Battery Charger (referred to as the battery charger). Read this guide carefully before operation and save it for future reference. Failure to observe the instructions or precautions can result in electrical shock, serious injury, or death, or can damage the battery charger, potentially rendering it inoperable.

Online Manual

Access the full online manual:

[Link to Quick Guide]

[Link to User Manual]

What's In the Box?

• Renogy 12V 20A/40A DC-DC Battery Charger x 1
• Quick Guide x 1
• Mounting Screws x 4 (ST4*16 mm)
• Battery Temperature Sensor (2 m) x 1
• IGN Signal Wire (3 m) x 1

⚠️ Make sure that all accessories are complete and free of any signs of damage. The accessories and product manual listed are crucial for installation. Please note that package contents may vary depending on the specific product model.

Dimensions

20A DC-DC Battery Charger (RBC20D1U)

Dimensions: 8.56 in (217.5 mm) width, 5.17 in (131.5 mm) depth, 2.75 in (70 mm) height.

40A DC-DC Battery Charger (RBC40D1U)

Dimensions: 8.56 in (217.5 mm) width, 6.00 in (152.5 mm) depth, 3.56 in (90.5 mm) height.

All models have a thickness of 1.59 in (40.5 mm).

Dimension tolerance: ±0.2 in (0.5 mm).

Get to Know Renogy Battery Charger

The battery charger features the following components:

• Battery Type Indicator
• Fault Status Indicator
• Battery Status Indicator
• Battery Type Setting Button
• Positive Output Terminal
• Negative Output Terminal
• Mounting Hole
• RS485 Communication Port
• Battery Temperature Sensor (BTS) port

The input terminals include:

• Positive Input Terminal
• Negative Input Terminal
• Mounting Hole
• IGN Signal Wire Port

⚠️ The Battery Temperature Sensor (BTS) port can only be used with lead-acid batteries.

System Setup

The system setup involves connecting the battery charger to a Starter Battery, Smart DC Alternator, and a 12V Auxiliary Battery, optionally with a Renogy BT-2 Bluetooth Module for monitoring. Connections are made using specific wires:

• Positive (Red wire)
• Negative (Gray wire)
• Temperature (Purple wire)
• Communication (Cyan wire)
• IGN Signal (Blue wire)

Required Tools

Before installation, gather the following tools:

• Phillips Screwdriver (#1) ?
• Insulating Gloves ?
• Measuring Tape ?
• Insulation Tape ?

⚠️ Prior to installing and configuring the battery charger, prepare the recommended tools, components, and accessories.

Step 1. Wear Insulating Gloves

Put on insulating gloves before proceeding with any electrical connections.

Step 2. Plan a Mounting Site

The battery charger requires adequate clearance for installation, wiring, and ventilation. Ensure a minimum clearance of 5.91 inches (150 mm) on all sides.

Environmental considerations:

• Operating Temperature: -40°F to 185°F (-40°C to 85°C)
• Operating Humidity: 0% to 95%
• Environment: Keep Dry, Protect from Fragile conditions, Ensure Ventilation, Indoor installation recommended.

⚠️ The battery charger should be installed on a flat surface protected from direct sunlight.

Step 3. Connect the Battery Charger to an Auxiliary Battery

The battery charger is compatible with deep-cycle gel-sealed lead-acid batteries (GEL), flooded lead-acid batteries (FLD), sealed lead-acid batteries (SLD/AGM), or lithium iron phosphate batteries (LI).

Recommended Components & Accessories

• 12V Battery (9V to 16V input range)
• ANL Fuse x 1 (RBC20D1U: 30A, RBC40D1U: 40A)
• Battery Adapter Cables x 2 (RBC20D1U: 10 AWG, RBC40D1U: 8 AWG)
• Fuse Cable x 1 (RBC20D1U: 10 AWG, RBC40D1U: 8 AWG)

⚠️ Accessories marked with "*" are available on renogy.com.

⚠️ For installation details, consult the user manual of the battery in use.

⚠️ To ensure optimal system performance, use cables no longer than 3 meters. For longer distances, choose higher gauge cables. Refer to the battery charger manual at www.renogy.com/support/downloads for details.

Installation Steps

STEP-1: Install cables on the battery charger

Connect the M5 terminals on the battery charger using the battery adapter cables.

STEP-2: Install an ANL fuse

Install the ANL fuse in the positive line between the battery charger and the auxiliary battery.

STEP-3: Install the cables on the battery

Connect the positive and negative battery adapter cables to the corresponding terminals on the auxiliary battery.

Step 4. Connect the Battery Charger to a Starter Battery

Before installing, consult your vehicle's user manual or manufacturer to ensure the alternator power does not exceed 720W (output current between 75A to 100A).

Recommended Components & Accessories

• ANL Fuse x 1 (RBC20D1U: 40A, RBC40D1U: 80A)
• Battery Adapter Cables x 2 (RBC20D1U: 8 AWG, RBC40D1U: 6 AWG)
• Fuse Cable x 1 (RBC20D1U: 8 AWG, RBC40D1U: 6 AWG)

⚠️ Accessories marked with "*" are available on renogy.com.

⚠️ The starter battery stops charging the auxiliary battery when the starter battery voltage drops below 12.7V.

Installation Steps

STEP-1: Install cables on the battery charger

Connect the M5 terminals on the battery charger using the battery adapter cables.

STEP-2: Install an ANL fuse

Install the ANL fuse in the positive line between the battery charger and the starter battery.

STEP-3: Install the cables on the RV starter battery

Connect the positive and negative battery adapter cables to the corresponding terminals on the starter battery.

Step 5. Install a IGN Signal Wire (for Smart DC Alternator)

IGN signal wiring is required for smart alternators only. To distinguish a smart alternator, refer to the battery charger's user manual. If the vehicle's DC alternator is smart, insert the IGN Signal Wire connector into the IGN signal wire port on the charger, and connect the other end to the smart alternator's ignition signal port.

⚠️ Consult the RV supplier for wiring details.

Step 6. Install a Battery Temperature Sensor

The temperature sensor measures the surrounding battery temperature to compensate the floating charge voltage when the battery temperature is low.

⚠️ Do not use the temperature sensor on a LiFePO4 (LFP) battery that comes with a battery management system (BMS).

Mount the sensor securely in close proximity to the battery.

LED Indicators

The battery charger turns on automatically after power on, with LED indicators showing the operating status.

Battery Status Indicator

• Solid: The battery charger is in standby mode, or the auxiliary battery is fully charged.
• Flash: Charging the auxiliary battery.

Fault Status Indicator

• Off: No fault.
• Solid: Short-circuit protection on auxiliary battery or starter battery.
• Slow flash: Reverse contact protection on starter battery.
• Solid: Overtemperature protection on auxiliary battery.
• Slow flash: Overtemperature protection on battery charger.
• Fast flash: Overvoltage protection on auxiliary battery.
• Jumping flash: Overdischarge shutdown protection on auxiliary battery.

Battery Type Indicator

• Solid: SLD/AGM (Sealed Lead Acid Battery)
• Solid: GEL (Gel Battery)
• Solid: LI (Lithium battery activation disabled)
• Solid: LI (Lithium battery activation enabled)
• Solid: User Mode
• Solid: FLD (Flooded Battery)

Standby Mode*: The battery charger is only connected to the auxiliary battery, and the auxiliary battery voltage is greater than 12V.

LED Patterns

Graphic expression of LED states:

Set a Battery Type

Upon installing the battery charger, set the correct battery type using the Battery Type Setting Button.

⚠️ It is essential to ensure the battery type setting is configured correctly to avoid potential damage to the battery charger, as incorrect settings void the warranty.

Setting Flow:

Press the Battery Type Setting Button to cycle through the types: SLD/AGM, GEL, LI (disabled), LI (enabled), User Mode, FLD.

USER Mode

Setting the battery type to User Mode allows customization of battery parameters via the DC Home app.

⚠️ When customizing settings, consult the battery manufacturer's user manual. For further assistance, contact the manufacturer.

⚠️ For detailed parameter settings, see the battery charger manual at renogy.com/support/downloads.

Monitor the Battery Charger

Recommended Components

The Renogy BT-2 Bluetooth Module is recommended for monitoring.

⚠️ Accessories marked with "*" are available on renogy.com.

⚠️ Ensure the DC Home app and Renogy ONE firmware are updated to the latest version before use.

Charging current can be customized through the DC Home app.

Download the DC Home App

Download the DC Home app and log in with your account to monitor and manage your battery charger.

Available on Google Play and the App Store.

⚠️ The DC Home app version may be updated; illustrations are for reference. Follow instructions based on the current app version.

⚠️ For optimal performance, keep your phone or RENOGY ONE within 10 feet (3 m) of the battery charger.

⚠️ Fault alarms can be received via DC Home and Renogy ONE. Log in to the app for troubleshooting details.

Short-Range Monitoring via DC Home App

Pair the battery charger with the DC Home app to monitor and modify parameters.

Follow the on-screen prompts in the app to search for and connect to the device.

Wireless Long-Range Monitoring

Recommended Component: RENOGY ONE Core.

The RENOGY ONE Core connects to the BT-2 module via Bluetooth and to the internet via Wi-Fi, enabling long-range monitoring through the My Renogy app.

Important Safety Instructions

General Safety

• Wear proper protective equipment and use insulated tools during installation and operation.
• Do not wear jewelry or other metal objects when working on or around the battery charger.
• Keep the battery charger out of the reach of children.
• Do not dispose of the battery charger as household waste. Comply with local, state, and federal laws and regulations, and use recycling channels as required.
• In case of fire, use a FM-200 or CO₂ fire extinguisher.
• Improper installation on a boat may cause damage to boat components. Have devices installed by a qualified electrician.
• Do not expose the battery charger to flammable or harsh chemicals or vapors.
• Clean the battery charger regularly.
• Do not puncture, drop, crush, penetrate, shake, strike, or step on the battery charger.
• Do not open, disassemble, repair, tamper with, or modify the battery charger.
• Connect the negative terminal prior to the positive terminal when connecting any device.
• It is recommended that all cables should not exceed 10 meters to avoid voltage drop.
• Cable specifications in this guide account for critical, less than 3% voltage drop and may not cover all configurations.

Battery Charger Safety

• Install the battery charger on a vertical surface, protected from direct sunlight, high temperatures, and water. Ensure good ventilation.
• Keep the battery charger away from heating equipment.
• Do not insert foreign objects into the battery charger.
• Confirm the polarities of devices before connection. Reverse polarity contact can damage the charger and void the warranty.
• Do not touch connector contacts while the battery charger is in operation.
• Disconnect all connectors before maintenance or cleaning.

Battery Safety

• Do not use batteries if there is any damage.
• Do not touch exposed electrolyte or powder if the battery is damaged.
• Risk of explosion! Never install the battery charger in a sealed enclosure with flooded batteries. Do not install in a confined area where battery gases can accumulate.
• Ensure all battery groups are installed properly before installing the battery charger.

Renogy Support

To discuss inaccuracies or omissions in this guide, visit or contact:

renogy.com/support/downloads

contentservice@renogy.com

For more on solar systems, visit the Renogy Learning Center: renogy.com/learning-center

Questionnaire Investigation: [QR Code]

Technical Support

For technical questions in the U.S.:

renogy.com/contact-us | ? 1(909)2877111

For technical support outside the U.S.:

• Canada: ca.renogy.com
• Australia: au.renogy.com
• South Korea: kr.renogy.com
• United Kingdom: uk.renogy.com
• China: www.renogy.cn
• Japan: renogy.jp
• Germany: de.renogy.com
• Other Europe: eu.renogy.com

FCC Statement

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference. (2) This device must accept any interference received, including interference that may cause undesired operation.

Any Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment causes harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• (1) Reorient or relocate the receiving antenna.
• (2) Increase the separation between the equipment and receiver.
• (3) Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• (4) Consult the dealer or an experienced radio/TV technician for help.

FCC Radiation Exposure Statement

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with a minimum distance of 20cm between the radiator and your body.

Disclaimer

Renogy 12V 20A/40A DC-DC Battery Charger Quick Guide © 2023 Renogy. All rights reserved.

RENOGY and [Renogy Logo] are registered trademarks of Renogy.

• All information in this quick guide is subject to copyright and other intellectual property rights of Renogy and its licensors. The quick guide may not be modified, reproduced, or copied, in whole or in part, without prior written permission from Renogy and its licensors.
• Registered trademarks in this quick guide are the property of Renogy. Unauthorized use of trademarks is strictly prohibited.
• Renogy ensures the accuracy, sufficiency, and applicability of information at the time of printing, due to continual product improvements.
• Renogy assumes no responsibility or liability for personal and property losses, whether direct or indirect, caused by the user's failure to install and use the product in compliance with this quick guide.
• Renogy is not responsible or liable for any failure, damage, or injury resulting from repair attempts by unqualified personnel, improper installation, and unsuitable operation.
• Illustrations in this quick guide are for demonstration purposes only. Details may appear slightly different depending on product revision and market region.
• Renogy reserves the right to change the information in this quick guide without notice. For the latest quick guide, visit renogy.com.

Renogy Power PLUS

Renogy Power Plus allows you to stay updated with solar energy innovations, share your experiences, and connect with like-minded individuals in the Renogy Power Plus community.

Connect with us:

• YouTube: @Renogy Solar
• Instagram: @renogyofficial
• Facebook: @Renogy

Renogy reserves the right to change the contents of this quick guide without notice.

Manufacturer: RENOGY New Energy Co., Ltd

Address: No.66, East Ningbo Road Room 624-625, Taicang German Overseas Students Pioneer Park, Jiangsu 215000 CN

EC REP: eVatmaster Consulting GmbH, Battinastr. 30, 60325 Frankfurt am Main, Germany, contact@evatmaster.com

UK REP: EVATOST CONSULTING LTD, Suite 11, First Floor, Moy Road Business Centre, Taffs Well, Cardiff, Wales, CF15 7QR, contact@evatmaster.com

RENOGY.COM