Proper CAN wiring is essential for stable communication between the BMS and connected devices like CMUs, inverters, chargers, etc.

CAN uses two lines: HIGH (CAN-H) and LOW (CAN-L)

All devices are connected in parallel along one continuous bus line

No star topology or long branches – only short drop lines (max. 500 mm) to each device

A 120 Ω resistor must be placed at each end of the bus

The BMS and last CMU typically provide termination if configured correctly

Only two resistors total on the bus – no more, no less

⚠️ Missing or incorrect termination leads to unstable or no communication

BMS: Master device

CMUs: Cell Management Units – multiple allowed

Other extensions: e.g. displays, current sensors, inverter Each device has a CAN HIGH / CAN LOW pair that must be connected to the main line.

🛠️ Make sure the CAN baud rate and ID settings match across all devices on the bus
Check under Connections → CAN Bus for configuration options