Can We Talk?

So you made a mint in the market and you’re ready to buy another sailboat. Great. But this time, you’re not skimming the classifieds—you’re heading straight for the showroom in search of that “new-boat smell.” But unless your sailboat manufacturer already offers some type of OEM package on the electronics, the choice of those electronics is mainly up to you.Your first step is to determine the type of electronics you need and where you’ll put all the transducers, antennas, and control heads (at the nav station? the wheel? If outside, are the displays daylight readable and waterproof?). But before you make the final decisions, you also need to consider how they’ll “talk” to each other so they can share information. Today, most marine electronics uses a data-sharing sentence developed by the National Marine Electronics Association (NMEA) called 0183. This data sentence has been around for years, and it was designed to let dissimilar electronic units from dissimilar manufacturers (such as a Brand-X GPS receiver and a Brand-Y electronic chart display) communicate with each other. In this way, your GPS receiver can determine your position and then transfer that data to your electronic chart so your sailboat’s position appears in its proper location on the chart.

While NMEA 0183 has arguably worked fairly well for years, the NMEA recently announced “an initiative to develop a new standard for data communications among shipboard electronic devices.” That new standard is called NMEA 2000, and you’ll be hearing a lot about it in the coming months and years.

According to NMEA 2000’s committee chairman Larry Anderson, the new standard is much more sophisticated than 0183. “With 0183,” says Anderson, “if one instrument was talking, everybody else on the system had to be quiet. But NMEA 2000 has been designed so we can have multiple units all taking at the same time.” And that, says Anderson, will allow units connected to the system to solve complex calculations such as current set and drift, which was previously unavailable with any real precision but is still of vital importance to racing sailors.

In addition to calculating new data, Anderson says NMEA 2000 “will move a lot more data, very fast, through multiple activities on the bus.” The “bus” in this case amounts to a cable which will be built-in as the backbone of new NMEA-2000 compliant boats. The cable itself will have up to 50 “nodes” or connection points so virtually any compliant item or sensor will be able to link into the bus and participate in the data sharing. The bus will have a physical limit of 200 meters which should be plenty of mileage for even the largest yachts, and although the bus is not designed to handle very-high data demands—such as transferring real-time video feeds from one monitor to another—it promises to move “relatively brief data messages, transmitted as needed or on-demand by use of query commands,” according to the standard’s former committee chairman Frank Cassidy. As far as its ability to transfer large quantities of data is concerned, Cassidy says, “It will have approximately 20 times the capacity of the existing NMEA 0183 standard,” so it’s highly unlikely that data will become bottled up in the network when multiple units—such as your instrument system, radar, and electronic chart display--are talking at once.

The NMEA invited all marine electronics manufacturers to become involved in the beta-testing of the standard, and companies such as Teleflex, Raytheon, Furuno, Trimble, Simrad, Northstar, Navionics, and others have agreed to participate. Unlike some proprietary data-transfer systems that allow communication only among units made by the same manufacturer, NMEA 2000 has been designed with an “open architecture” which lets any manufacturer design a product that’s compliant with the system. When I asked Anderson whether those companies that DO have proprietary systems objected to the new standard, he responded, “Quite the opposite. Those manufacturers will continue producing their own high-speed data systems, yet they will be designed so they can link in with NMEA 2000 as well,” so data can flow freely between proprietary products and those of other manufacturers. In other words, if you purchase an OEM electronics package made by Brand-X for your new sailboat, the chances are good that system will also interface easily with other electronics you may want to add to your boat later on (but check this out with Brand-X before you buy).

While ease of installation and high-speed communications are the primary goals of the new standard, the NMEA also says the system is designed so that if one piece of electronics suffers a fault such as a power loss, it will not affect any other device on the bus. If, however, a device is disconnected from the bus, that might mean “a possible temporary network interruption and/or re-initialization of network-connected devices.”

In addition to linking traditional marine-electronics items like radars and electronic charts, Anderson also says the new standard is ready for the growing presence of personal computers aboard sailboats. “Sophisticated systems like ECDIS [Electronic Charting Display and Information Systems] will hook into the network okay, and fixed computers and laptops will be able to hook on as well. In this case the issue of whether or not the PC will work with the system is really a question of the programming built-in to each software package,” as opposed to the design of the computer itself.

So when can we expect to see this new system in action? Anderson says a number of electronics manufacturers are involved in beta-testing of NMEA 2000 at the time of this writing, and “our intent is to have the standard available by the first or second quarter of 2001. I can tell you that participating manufacturers are designing new products now to meet the standard.”

So what’s the bottom line to you? It appears that thanks to NMEA 2000, you will have much more flexibility in choosing marine electronics than you do now. You can either go with a proprietary system of components all made by the same manufacturer, or you can pick and choose your own items from various manufacturers with a lot more confidence in their ability to communicate with each other. As with any new technology, it is reasonable to expect a few “bugs” in the early days of NMEA 2000’s rollout, but going forward the system promises to put the power of choice right back in to your hands while removing the issue of “Can We Talk?” from the field of marine electronics.