What is the maximum number of physical devices that may be connected to a single NMEA 2000 network?

• A. 25 devices
• B. 100 devices
• C. 50 devices
• D. 75 devices

Answer: (C)

On a NMEA 2000 network, devices share a single CAN backbone, and the standard sets a practical limit on how many devices can be connected to that backbone: up to 50 physical devices. This cap helps keep bus loading and message timing within reliable bounds, ensuring all devices can access the bus efficiently and communications remain timely.

If you need more than 50 devices, you would use multiple networks and connect them through gateways or other inter-network solutions. That way, each network stays within its 50-device limit while the overall system can still support many devices across the vessel.

The other numbers don’t fit because they don’t align with the standard’s stated limit for a single network, which is designed to balance reliability and performance on the CAN-based backbone.