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Part 2: NMEA 2000 continued
 
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Some indication of the impact these standards will have once they become industry-wide already exists in proprietary interface systems designed by individual manufacturers that allow a high level of communication between only the components in their lines. MerCruiser’s SmartCraft is a good example. This system-integration technology links engine data such as rpm, fuel flow, oil pressure, and coolant temperature with data derived from a GPS, depthsounder, and other components. Added to the pool is information derived from electronic sensors for rudder angle and trim tab position, fuel load, freshwater and waste tank levels, and more. This wealth of intelligence is not collected just for the sake of a head-spinning array of readouts at the helm. It is processed, passed back and forth between pertinent components all working together to draw conclusions—and perhaps even take action—based on their combined analysis. “Conversations” between your GPS, fuel-flow meter, and fuel-tank level sensors will result in an accurate, up-to-the-minute calculation of your cruising range. An anomaly in the relationship between your fuel flow and rpm combined with your engine’s electronic memory of past maintenance could result in a notification at the helm that it’s time to change your fuel filters again.

NMEA 2000’s open architecture will allow similarly sophisticated relationships to exist between components from many different manufacturers. What’s more, proprietary interface systems such as SmartCraft and those being developed by Simrad, Volvo Penta, Teleflex, and others are likely also to become NMEA 2000-compliant and will link with certified components made by any other manufacturer. (As an example of how the new protocols can make it easier for two devices made by different companies to exchange data, Anderson mentions that you could replace one brand of depthfinder with another without having to change the transducer.) Once it gets going, the freer flow of information will finally allow all that impressive computing capacity packed into your electronics to work to its full potential.

But should the thought of all that interaction crowded onto one bus give you pause? If you throw a bunch of motor-mouth wise guys (from the States, Japan, Sweden, and elsewhere) into the same room, aren’t arguments bound to break out? The engineers at NMEA have taken steps to forestall any such likelihood. “In order to ensure that there will be no misunderstanding in the digital interface, we’ve designed a whole system defining priorities among the components,” says Anderson. “There are some products that are much more crucial to safety than others. You certainly wouldn’t want a control for cabin lights interfering with shifting an engine. If there is ever a negotiation of who’s going to be heard first, the outcome is always based on the hierarchy we have set using our marine knowledge.”

Boaters can also be reassured that the rigorousness of the beta testing, on-going since January 2000, should thoroughly debug the system by the time it is introduced industry-wide. Anderson anticipates publication of the protocols in June or July of this year, so it may not be long before your boat will support its own fast, floating Internet. Or “NavigationNet?” “WheelhouseWeb?” POkay, we can’t all be Al Gore.

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This article originally appeared in the January 2003 issue of Power & Motoryacht magazine.

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