CAN Communication Connections | Overview

CAN communication is an internationally standardized serial communication protocol primarily used in automotive and industrial control applications. It enables high-speed, reliable data transmission through two signal lines (CAN_H and CAN_L).

Importance of CAN Communication

The CAN protocol allows Renogy devices to interconnect, facilitating data exchange and collaborative control. This enhances the intelligence of energy management and the reliability of the system, ensuring safe operation, intelligent control, remote monitoring, and programmable settings.

In off-grid power systems, CAN communication primarily meets the need for high-reliability data interchange among devices. Its core value is reflected in several aspects:

• Devices Collaborative Management: CAN communication supports real-time data exchange between inverters, solar controllers, and batteries. For example, the inverter retrieves battery voltage, temperature, and status via CAN, dynamically adjusting charge and discharge strategies to optimize energy efficiency. The controller sends power scheduling commands to the inverter based on load demand, ensuring stable system operation.
• Real-Time Monitoring and Diagnostics: By transmitting operational parameters (such as inverter output waveforms, battery health status, and photovoltaic array power generation) through CAN, users can remotely monitor system performance via the Renogy ONE Core and Renogy APP. An integrated error detection mechanism can instantly report device failures (like overvoltage or overheating), significantly enhancing the system's fault tolerance.
• Interference Resistance: The differential signal transmission (CAN-H/CAN-L) design provides strong resistance to interference in complex electromagnetic environments typical of off-grid scenarios (such as mountainous regions or islands).
• Multi-Device Expansion Capability: With a multi-master control architecture, new devices can be easily integrated without modifying existing protocols, facilitating future scaling of off-grid systems.

How to Determine if a Device Supports CAN Communication

You can check if a device supports CAN communication using the following methods:

• Consult the User Manual: Review the device's user manual for information on communication protocols.
• Check the Technical Specification Sheet: Verify the communication specifications to confirm support for the CAN protocol.
• Contact Customer Support: Reach out to customer service for assistance.

CAN Communication Connection Diagram

Connect the Renogy devices that support CAN communication in sequence using communication cables. Insert the corresponding communication terminal resistors(s) into the available CAN ports on the first and last devices to complete the connection.

Required Accessories

A Renogy ONE Core is required to establish communication between Renogy devices. For devices with only one CAN communication port, you can purchase an RJ45 Network 1 to 2 Port Ethernet Adapter Splitter on your own.

Choose the Right Connector

Renogy devices have three types of communication ports, and you need to select the corresponding connector based on the port type. You can determine this by appearance.

When purchasing connectors, choose communication cables of appropriate length based on the distance between devices. It is recommended to buy communication cables that convert connectors to bare wires, rather than purchasing connectors separately, to reduce installation difficulty.

If the communication port is fixed with a clip, please use the LP-16 7 Pin Circular Aviation Connector.

If the communication port is fixed with a thread, please use the 7 Pin Circular Aviation Connector.

If the communication port is an RJ45 port, please use the 8-Pin RJ45 Connector.

Purchase or Create Communication Adapter Cables

Purchase Communication Cables

If the devices have the same CAN communication ports, you can directly purchase the corresponding dual-connector communication cable. For example:

Create Communication Adapter Cables

If the devices have different CAN communication ports, you can create your own adapter cable. First, understand the pin definitions and their corresponding wire colors. The wire colors in this document are for reference only; please refer to the actual colors, and if you have questions, consult your communication cable dealer.

Please note that the pin order between the ports and connectors is mirrored. In some communication cables, the CAN_GND pin may not have a wire; in this case, you can leave it unconnected.

①Understand Terminal Definitions and Wire Colors

• LP-16 7 Pin Circular Aviation Connector

Note that the pin definitions for the G1 version of the REGO 12V 400Ah LiFePO4 Battery (SKU: RBT12400LFPL-SHBT) are different from other devices. CAN_H is pin 5, CAN_L is pin 7, and CAN_GND is pin 2.

• 7 Pin Circular Aviation Connector

Note that the pin definitions for the G1 and G2 versions of the Renogy 12V/24V 50A IP67 Dual Input DC-DC On-Board with MPPT Battery Charger (SKU: RBC2125DS-21W-G1 / RBC2125DS-21W-G2) are different from other devices. CAN_H is pin 4, CAN_L is pin 3, and CAN_GND is pin 5. The pin definitions for the G3 and later versions are the same as those listed above.

• 8-Pin RJ45 Connector

When creating an LP-16 7 Pin Circular Aviation Connector to 8-Pin RJ45 connector or 7 Pin Circular Aviation Connector to 8-Pin RJ45 connector, you only need to prepare a separate 8-Pin RJ45 connector and a wire crimper.

②Making the Adapter Cable

Once you understand the wire colors corresponding to each pin of the connector, you can start making the adapter cable. Different types of adapter cables require different tools; please refer to the steps below for details.

You only need to connect the wires corresponding to CAN_H, CAN_L, and CAN_GND; the other pin wires do not need to be connected. In some communication cables, the CAN_GND pin may not have a wire; in this case, you can leave it unconnected.

• LP-16 7 Pin Circular Aviation Connector to 7 Pin Circular Aviation Connector Adapter Cable

First, prepare the following two communication cables:

1. Stripping Wires: Use wire strippers to remove the insulation from the bare wire ends of the communication cables.

2. Connecting Wires:

• CAN_GND: Connect the green wire from pin 4 of the LP-16 7 Pin Circular Aviation Connector to the yellow wire from pin 4 of the 7 Pin Circular Aviation Connector.
• CAN_H: Connect the white wire from pin 5 of the LP-16 7 Pin Circular Aviation Connector to the white wire from pin 5 of the 7 Pin Circular Aviation Connector.
• CAN_L: Connect the blue wire from pin 7 of the LP-16 7 Pin Circular Aviation Connector to the blue wire from pin 7 of the 7 Pin Circular Aviation Connector.

3. Insulation: Use electrical tape to wrap each of the three connection points.

• LP-16 7 Pin Circular Aviation Connector to 8-Pin RJ45 Connector

First, prepare the communication cable and RJ45 connector as shown below.

1. Connecting Wires:

• CAN_GND: Insert the green wire from pin 4 of the LP-16 7 Pin Circular Aviation Connector into pin 5 of the RJ45 connector.
• CAN_H: Insert the white wire from pin 5 of the LP-16 7 Pin Circular Aviation Connector into pin 3 of the RJ45 connector.
• CAN_L: Insert the blue wire from pin 7 of the LP-16 7 Pin Circular Aviation Connector into pin 1 of the RJ45 connector.

2. Crimping

Use a wire crimper to secure all the wires inside the RJ45 connector.

• 7 Pin Circular Aviation Connector to 8-Pin RJ45 Connector

First, prepare the communication cable and RJ45 connector as shown below.

1. Connecting Wires:

• CAN_GND: Insert the yellow wire from pin 4 of the 7 Pin Circular Aviation Connector into pin 5 of the RJ45 connector.
• CAN_H: Insert the white wire from pin 5 of the 7 Pin Circular Aviation Connector into pin 3 of the RJ45 connector.
• CAN_L: Insert the blue wire from pin 7 of the 7 Pin Circular Aviation Connector into pin 1 of the RJ45 connector.

2. Crimping:

Use a wire crimper to secure all the wires inside the RJ45 connector.

Communication Connection

1. How to Properly Install Connectors on the Device Port

Shaking the connector while plugging or unplugging it is not allowed.

• LP-16 7 Pin Circular Aviation Connector

To properly connect or disconnect the LP-16 7 Pin Circular Aviation Connector to or from the device, you should:

1. Ensure that the connector is oriented vertically toward the CAN Communication Port.

2. Press and hold the snap until the process is complete.

• 7 Pin Circular Aviation Connector

To properly connect or disconnect the 7 Pin Circular Aviation Connector to or from the device, you should:

1. Ensure that the connector is oriented vertically toward the CAN Communication device.

2. Rotate the connector fixing nut to loosen or secure the connector.

• 8-Pin RJ45 Connector

To properly connect or disconnect the 8-Pin RJ45 Connector to or from the device, you should:

Ensure that the RJ45 connector is oriented vertically toward the CAN Communication Port.

2. Connecting Communication Cables Between Devices

1. Use the prepared communication cables to connect the Renogy devices that support CAN communication through their CAN communication ports in sequence.

2. Insert the corresponding terminal resistors(s) into the available CAN communication ports at both ends of the devices to complete the communication connection for the Renogy devices.

Terminal resistors can be purchased through the Renogy official website. Terminal resistors should be chosen based on the port type, as detailed below:

How to Connect the Renogy ONE Core

• Core located at the first or last position in the communication network

• Core located in the middle of the communication network

Pair Renogy ONE Core with the Renogy app. Monitor and program the complete system on the Renogy ONE Core or the Renogy app.

For wiring instructions on Renogy ONE Core, see Renogy ONE Core User Manual.