Maintaining and Upgrading Your NMEA 2000 Network

The NMEA 2000 network is the backbone of modern marine electronics, connecting everything from GPS systems and fish finders to engine monitors and autopilot systems. Whilst NMEA 2000 is a very robust system, utilising CAN, there is still a requirement to perform maintenance and sometimes upgrade equipment (this could be essential or desirable).

Why NMEA 2000 Maintenance is Important

Regular maintenance of your NMEA 2000 network ensures the reliable operation of connected devices, prevents data transmission issues, and extends the life of the network components. Neglecting maintenance can lead to poor performance, communication failures, and even damage to expensive equipment.

Tips for NMEA 2000 Network Maintenance

1. Regular Inspection of Cables and Connections

One of the most common issues with NMEA 2000 networks is poor connections between cables and T-pieces due to excess strain or overtightening/cross-threading. Inspect cables, connectors, and T-pieces regularly for signs of damage, corrosion, or looseness. Replace these where necessary, as they are a low-cost component which can solve a lot of interconnectivity headaches.

2. Clean and Protect Connections

Marine environments are harsh, with salt water, humidity, and temperature fluctuations contributing to corrosion and degradation. Ensure that your cables and connectors are designed to withstand the conditions. Using metal connectors like those found on the Actisense A2K range is a surefire way of improving reliability thanks to their robust design.

3. Check for Proper Termination and Power Supply

An NMEA 2000 network requires proper termination at both ends of the backbone and a stable power supply. Ensure that terminators are correctly installed, that there are only two terminators on the backbone, and that the power supply is within the required 9-16VDC range. An underpowered or overpowered network can lead to communication errors or device malfunctions.

4. Monitor Network Traffic

Using an NMEA 2000 gateway such as an NGX-1 is highly recommended for network recording and monitoring. By using an Actisense NGX-1 in combination with NMEA Reader, you can see all devices on the network, and the data being output, including the rate at which PGNs are being sent.

Upgrading Your NMEA 2000 Network

Sometimes upgrades are essential if equipment has failed, and other times it is just a ‘want’, for a new, bigger display or a more accurate GPS etc… some things to consider when performing upgrades and adding extra devices onto the bus are:

1. Assess Current Network Capacity

Before adding new devices, assess your current network’s capacity. NMEA 2000 networks can have power issues on large networks, where devices at the extremities of long backbones with multiple devices do not receive enough power to operate correctly.

2. Upgrade to Higher Quality Cables and Connectors

If you plan to add more devices, consider upgrading to higher-capacity cables and connectors. Look for NMEA 2000-certified cables that offer better shielding and durability, especially if you operate in a challenging environment.

An excellent way of reducing the voltage drop across a network is to change from Micro to Mid cable. Whilst this is a time-consuming exercise for pre-existing networks, the resistance per metre of mid-cable is much lower, so the power drop is lower too.

3. Add More Power Nodes

As you expand your network, ensure that your power supply is adequate. You may need to add more power nodes to distribute power evenly across the network, preventing voltage drops and ensuring stable operation.

4. Integrate New Devices Seamlessly

When adding new devices, ensure they are NMEA 2000-certified so there will not be any interference when adding additional instruments. Always follow the manufacturer’s installation instructions and test the network thoroughly after installation to ensure everything is functioning correctly.

Conclusion

Maintaining and upgrading your NMEA 2000 network is vital for ensuring the reliability and performance of your boat’s electronics. Regular inspections, careful upgrades, and staying informed about the latest standards will help you keep your network in top condition.