Understanding PGNs: NMEA 2000 and J1939

In marine electronics, seamless communication and data exchange between different onboard systems are essential for safe navigation and enhanced boating experiences. To achieve this, various protocols and standards are employed, such as NMEA 2000 and J1939. At the heart of these protocols lies a fundamental element known as Parameter Group Number (PGN). In this article, we’ll delve into what a PGN is, its significance in marine electronics, and its role within the NMEA 2000 and J1939 frameworks.

Defining PGN: The Data Building Block

A Parameter Group Number (PGN) is a unique numerical identifier used to categorize and define specific sets of data within the NMEA 2000 and J1939 communication protocols. Think of it as a code that groups together related data, allowing devices on a network to recognize and interpret information efficiently.

PGN in NMEA 2000: Enhancing Marine Connectivity

NMEA 2000 has emerged as a standardized protocol that facilitates data exchange between various devices onboard, such as GPS units, depth sounders, engines and more. PGNs play a pivotal role in the NMEA 2000 ecosystem by categorizing different types of data that need to be shared.

For instance, PGN 126208 represents vessel speed, and PGN 127245 relates to the engine’s fluid levels. Each PGN is associated with a specific data type, making it easier for devices to interpret and utilise the information. By adhering to the PGN structure, NMEA 2000 ensures that disparate devices can communicate effectively, providing accurate and real-time data to boaters.

PGN in J1939: Connecting Onboard Vehicle Systems

While NMEA 2000 focuses on marine electronics, the J1939 protocol is primarily utilized in heavy-duty vehicles and industrial applications. Despite the differences in application, both protocols share the concept of PGNs to enable efficient communication. In the context of J1939, PGNs serve to connect various systems within a vehicle, including engines, transmissions, and brakes.

For instance, PGN 65262 might represent an engine’s status, while PGN 61444 could indicate the transmission’s current state. Just as in NMEA 2000, PGNs in the J1939 protocol ensure that data is structured and organized for clear communication between systems.

Conclusion: PGNs and the Future of Marine Electronics

In marine electronics, where real-time data exchange is crucial for navigation, safety, and convenience, the concept of Parameter Group Numbers (PGNs) is the bedrock upon which effective communication is built. PGNs provide a standardized way to categorize, transmit, and interpret data, ensuring that network devices can seamlessly communicate despite their diverse functions.

As technology continues to evolve and boats become more integrated and data-driven, the concept of PGNs will remain vital. Whether you’re monitoring engine parameters, GPS coordinates, or fluid levels, understanding PGNs is a fundamental step towards harnessing the power of marine electronics and enjoying a safe and enjoyable boating experience.

Having access to ‘mission critical’ vessel data such as engine parameters, GPS, AIS and compass data is something we always kept at the forefront of our NMEA 2000 product development. We want to give the boat owner access to as much of their data as possible, in a simple and user-friendly method that they can interpret without needing assistance. Using products such as the Actisense EMU-1 and NGT-1 together will allow greater visibility of your NMEA 2000 PGNs, especially when combined with NMEA Reader.