REC DB9 to RJ45 CAN-Bus Cable (Victron Cerbo/ Venus/ CCGX)

REC DB9 to RJ45 CAN-Bus Cable: Reliable Communication Between REC BMS and Victron GX Devices

Purpose-Built CAN-Bus Cable for Seamless BMS Integration

The REC DB9 to RJ45 CAN-Bus Cable provides a direct, reliable link between your REC Active BMS or REC Q BMS and Victron GX devices such as the Cerbo GX, Venus GX, or Color Control GX. This cable enables real-time battery monitoring and control by transmitting CAN-bus data from the BMS to the Victron ecosystem, ensuring your energy storage system operates with precision and safety.

Engineered for compatibility with the REC BMS CAN-bus protocol, this cable supports both 500 kbit/s (Cerbo GX) and 250 kbit/s (other GX devices) data rates. It eliminates guesswork and custom wiring, reducing installation time and the risk of communication errors that can lead to system faults or battery damage.

Key Features

• Plug-and-Play Connectivity: Pre-terminated DB9 female connector for the REC BMS CAN port and RJ45 connector for the Victron GX device, with no soldering or crimping required.
• Integrated Termination: Includes a matched RJ45 termination plug with 120 Ohms across CANH and CANL, ensuring proper bus termination for stable communication.
• Durable Construction: High-quality cable jacket resists abrasion and environmental stress, suitable for permanent installations in battery compartments or control cabinets.
• Precision Wiring: DB9 pinout follows REC specifications: Pin 2 (CANL + termination), Pin 3 (GND), Pin 7 (CANH + termination), guaranteeing correct signal integrity.
• Versatile Compatibility: Works with REC Active BMS (4 cells) and REC Q BMS (5-16 cells), covering a wide range of lithium battery configurations.

Why Proper CAN-Bus Cabling Matters

In a CAN-bus BMS system, the physical layer is critical. Poor-quality cables or incorrect termination can introduce signal reflections, data corruption, and intermittent communication dropouts. This REC cable is designed to meet the exact impedance and termination requirements of the Victron CAN-bus network, reducing the risk of BMS communication failures that could lead to overcharge, undercharge, or cell imbalance.

Unlike generic DB9-to-RJ45 adapters, this cable includes the necessary end-device termination resistor, which is often overlooked in DIY setups. Without proper termination, the CAN bus may become unreliable, especially in electrically noisy environments like engine bays or inverter compartments.

Installation Guidance

Connect the DB9 end to the CAN port on your REC BMS, and the RJ45 end to the BMS-Can port on a Cerbo GX, or the VE-Can port on other GX devices. Insert the supplied termination plug into the unused CAN socket on the GX device to complete the bus. For optimal performance, ensure the cable is routed away from high-current power cables to minimise electromagnetic interference.

This cable is specifically designed for REC BMS to Victron GX communication and is not intended for use with other BMS brands or non-Victron devices without verifying pinout compatibility.

Applications

• Integrating REC BMS with Victron Cerbo GX for remote monitoring via VRM Portal
• Enabling closed-loop communication between REC-managed lithium batteries and Victron inverter/chargers
• Retrofitting existing battery systems with CAN-bus control for improved state-of-charge accuracy
• Professional marine, RV, and off-grid solar installations requiring robust BMS data links

Get Connected with Confidence

Ensure your REC BMS and Victron GX device communicate flawlessly. Add the REC DB9 to RJ45 CAN-Bus Cable to your system today and benefit from reliable, real-time battery management data.