NMEA2000: what is it and which are the advantages?
NMEA2000 is a communication protocol used in the marine environment characterized by an open architecture. Precisely this peculiarity guarantees complete and fast interoperability between engines, sensors and instruments as never before possible. We are not talking, therefore, of a company or a product, but of a solution that serves to ensure the full reliability of certified products: a plug and play standard that does not require additional configurations once the necessary connections have been made. NMEA is the acronym that identifies the National Marine Electronics Association, a non-profit organization that aims to promote navigation and the organization of operational safety, thanks to specific industry standards. NMEA also deals with technical training and, with over 500 members distributed internationally, it serves the public interest by involving private operators and producers, but also distributors and public organizations.
What is NMEA2000 used for
NMEA2000 is a reality destined to win the appreciation of those who believe that interoperability between instruments is a fundamental aspect in the navigation sector. This data communication standard is a guarantee of reliability for marine electronics and allows for the creation of networks of instruments on board vessels. It is no coincidence that all manufacturers of echoes, radar, gps, engines and marine electronics are in the process of setting aside the proprietary protocols they have used up to now to propose NMEA2000 certified instruments. By virtue of this solution, a single system allows you to network and monitor all the elements, from monitors to alarms, from sensors to GPS, as well as – obviously – engines.
The characteristics of NMEA2000
This reality is based on a bidirectional digital protocol that was conceived in the automotive sector: however, the benefits offered for marine applications are evident, since it is possible to access all the critical data of the sensors and equipment on any device and anywhere. . With a single bus, NMEA2000 allows you to contain costs, since the amount of cables required decreases: which allows, among other things, to facilitate on-board installations and to simplify any future changes. While proprietary standards generally force you to refer to a single brand, in this case products of different brands can be put in communication with each other, as if they spoke only one language.
Simplicity is a peculiar feature of the network, which is based on the backbone: this corresponds to the main bus, and consists of a data cable which ultimately represents the backbone of the entire network. Typically the cable runs along the length of the boat, and there are two 120 Ohm end terminators. The bus power supply offers a significant advantage, as it makes direct connection to the stand-alone sensor network possible. For example, gps sensors, depth sensors, temperature sensors or fuel level sensors can be connected, all to a single bus and using mains power.
What has changed with NMEA2000 networks
Thanks to NMEA2000 networks, a new path for interfacing engines with various instruments, including plotters, has started. Today’s engines can be NMEA2000 interfaced, so as to make the parameters of the Engine Control Units available and communicate them on the network. These interfaces make it possible to view the operating temperatures of the motors and the instantaneous consumption on the plotters, but also the alarms and any other type of information on the functioning of the engine control unit.
Compatible plotters are nothing more than data viewers. The data may concern the flap inclination, the trim inclination, the radar, temperatures, consumption, and so on. Users have the opportunity to configure the windows as they prefer and customize the screens, for example by merging multiple data displayed together. While the latest generation motors provide for a direct connection, for older models it is sufficient to refer to the electronic probes: these are converter adapters through which the motor control unit is interrogated in the proprietary format; after which the information is converted into the NMEA2000 format. Lowrance and Maretron are the main manufacturers of interfaces and electronic probes for outboard motors.
All data relating to pressure, temperatures, consumption and engine can be displayed on additional instruments or directly on the chart plotter. Through the instrumentation, therefore, you have the opportunity to take advantage of a more efficient consumption management, for example to find out how much autonomy you still have available. It is easy to understand, at this point, why the manufacturers of outboard motors, depth sounders, radar and gps have decided to convert their proprietary protocols and switch to the NMEA2000 standard, so as not to run the risk of coming exclusive. In order to work on the NMEA2000 network, the products must be certified. Recognizing certified products is easy, because they are equipped with the NMEA2000 logo; those that are declared only NMEA2000 compatible, however, are not certified and therefore do not give guarantees of being able to function adequately.
Prospects for the future
In theory, there are endless prospects for the future, even if it’s never easy to make predictions. At present there are already adapters that allow you to connect a computer with a NMEA2000 network, in order to enter data on the network or read them through a PC. These are adapters that allow, among other things, to save data inside the computer: this means having black boxes available with a kind of data logger and an archive of information that can range from the direction of the wind to the GPS position, without forgetting the weather data and those of the engine. Thus, it will be easy to find out at what speed you were driving at a certain point, what was the fuel consumption, what was the number of engine revolutions, etc. Further innovations could derive, then, from wireless solutions, ie wireless.