REC 2Q BMS wiring harness

REC 2Q BMS Wiring Harness: Precision Connectivity for Advanced Battery Management

Engineered for Seamless Integration with REC 2Q BMS Systems

The REC 2Q BMS wiring harness is a purpose-built cable assembly designed to connect the REC 2Q Battery Management System to your lithium battery bank with accuracy and reliability. This harness eliminates the guesswork and potential faults of generic wiring, providing labelled, pre-configured connections that streamline installation and enhance system integrity. Whether you are commissioning a new off-grid energy storage system, upgrading an existing setup, or replacing a damaged harness, this assembly ensures your BMS communicates effectively with cells, sensors, and external devices.

In complex DC power systems, signal integrity is critical. Poor-quality or improvised wiring can introduce noise, voltage drops, and intermittent connections that compromise battery monitoring and protection. The REC 2Q harness uses high-quality connectors and clearly identified conductors to maintain stable data transmission and accurate cell voltage readings, reducing the risk of BMS faults and system downtime.

Key Features at a Glance

• Pre-assembled connectors for all five 2Q BMS ports, eliminating wiring errors
• Labelled cell sense wires for 4 to 16 lithium cells, simplifying termination
• Integrated CAN Bus lead with Weipu SP13 connector for Victron and other compatible devices
• Dual DS18B20 digital temperature sensors for precise thermal monitoring
• Shunt sense cable with 4mm lugs for accurate current measurement
• Remote ON/OFF switch and configurable I/O wires for external control and alarms
• Spare RS485 connector included for custom industrial interfaces

Complete Connectivity for Your BMS

This harness covers every interface on the REC 2Q BMS, ensuring you have the right connections from the start. The CELLS connector provides 17 labelled wires (Cell 1- to Cell 16+) plus Pack - and Pack + power supply leads, all cut to a 2-metre length for flexible routing within your battery enclosure. A dedicated pre-charge wire is also included, supporting safe system startup without the need for additional components.

The Isens Tsens connector features two DS18B20 digital temperature sensors and a shunt sense cable terminated with 4mm lugs. The temperature sensors allow the BMS to monitor cell or ambient temperatures at two points, enabling precise thermal management and protection. The shunt sense cable connects directly to a battery shunt, with the "+" lug clearly marked for the battery side, ensuring correct polarity and reliable current data.

CAN Bus and Communication Integration

The RS485 CAN T Cp connector includes a 0.5-metre CAN Bus lead terminated with a Weipu SP13 circular connector. This interface is commonly used to link the BMS with Victron GX devices, inverters, and other CAN-enabled equipment. A termination jumper is pre-installed on the "T" pins, simplifying network setup. For RS485 communication, the harness provides a spare connector with pins on the RS485-0 port, allowing installers to wire a custom interface for industrial RS485 networks without sourcing proprietary plugs.

Note: While the CAN lead uses a Weipu SP13 connector, many inverters and controllers require an RJ45 connection. A separate CAN Bus adapter cable (available from REC) may be needed to match your specific device pinout, as there is no universal standard for CAN RJ45 wiring.

Control and Monitoring Flexibility

The I/O connector brings out essential control and monitoring signals on a 1-metre cable. It includes a remote ON/OFF micro rocker switch, allowing convenient manual control of the BMS without accessing the unit directly. Additional labelled wires—OPTO RELAY IN, OPTO RELAY OUT, OC 1-, OC 1+, OC 2-, OC 2+—provide open-collector outputs and an opto-isolated relay interface for external alarms, contactors, or automation systems. This flexibility supports integration into larger energy management setups, from marine and RV applications to off-grid residential systems.

Built for Demanding Environments

All connectors are genuine TE Connectivity (AMP) parts, selected for their proven reliability in high-vibration and temperature-cycling conditions. The use of locking connectors prevents accidental disconnection, while the labelled wires reduce installation time and the potential for miswiring. This harness is suitable for use in mobile, marine, and stationary energy storage applications where dependable BMS operation is essential for battery safety and longevity.

Why Choose the REC 2Q Wiring Harness?

Using the correct wiring harness is a critical step in ensuring your REC 2Q BMS performs as designed. Generic or field-assembled cables often lack the proper connector housings, pin assignments, and wire gauges, leading to unreliable connections and potential damage to the BMS or battery cells. This harness is built to REC's specifications, providing a plug-and-play solution that protects your investment and reduces commissioning time.

By maintaining accurate cell voltage sensing, stable communication, and reliable temperature and current monitoring, this harness helps the BMS protect your lithium cells from over-voltage, under-voltage, over-temperature, and over-current conditions. It is an essential component for anyone serious about battery performance and safety.

Order Your REC 2Q BMS Wiring Harness Today

Equip your REC 2Q BMS with the connectivity it deserves. Whether you are building a new lithium battery system or maintaining an existing one, this wiring harness delivers the precision and reliability you need. Add to cart now and ensure your battery management system operates at its full potential.