Intelligent Electricity

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It’s likely that your electric windlass and/or bow thruster has already given you a taste of what’s called distributed power. The thick cables needed to carry the DC juice usually run directly from a battery bank through a large fuse to the power-hungry motor, not via the switch or joystick at your helm. Thanks to a relay those controls use light wires, and hence extra controls, even wireless ones, are easy to add. But it’s also likely that the full load of most electrical gear on your boat is cabled to a large central circuit-breaker panel and then out to where it’s needed. The various distributed power systems now being built into many new yachts, and retrofitted into a few older ones, aim to eliminate those panels, and to create many bonus features in the process.

One hallmark of distributed power is remotely controlled breaker modules efficiently distributed close to where they’re needed around a boat. The overall reduction in cable mess and weight can be profound. Moreover, the circuit protection and switching is not done by a simple fuse and relay, but rather by a modern solid-state innovation called a MOSFET (for “metal oxide semiconductor field-effect transistor,” if you must know). MOSFETs can be set up, switched, and diagnosed by a few data bytes running through a network bus, and they also can both control and sense the amount of current passing through. Mix in a few microprocessors with some clever programming, and the magic begins: A distributed power system, for instance, can keep track of how often and how long the bilge pumps run, and can also broadcast an alarm around the vessel—maybe even off the vessel—if one of them is clogging up, as that situation will cause a higher current draw.

Thus distributed power is alternately identified as intelligent, digital, multiplexing, or some combination of those buzz words. And the various manufacturers who have bravely entered this complex niche, but can’t reach consensus on what to call it, will no doubt come up with more terms before the technology settles out. It’s already clear, though, that once you electronically manage a yacht’s electrical system, there’s virtually no limit to what’s possible. For example, MOSFET digital switching and current control abilities mean that whole-cabin dimming is relatively easy, and whole-boat “scenes” are possible. Consider a night running mode in which courtesy, chart table, and navigation lights are all activated with a single command, and you’ll be informed if one of the latter’s bulbs blows. Other scenes might have roles for electric blinds, power hatches, HVAC, lava lamps...whatever!

Consider, too, that such commands can emanate from traditional-looking switch banks, even if complex scenes have to be set up with a PC or one of the dedicated touchscreen PCs usually available in higher-end systems. That’s because all distributed power schemes include digital-switching modules and/ or interfaces able to incorporate dumb switches into a smart network. And while distributed power networks are innately good at monitoring a boat’s electrical flows, it’s relatively easy, and advantageous, to integrate sensors like those minding tanks and batteries and even those involved with security, navigation, and more. If there’s a GPS in the system, it can know when to turn on the anchor light. A diesel day tank level falling below 20 percent can trigger a system wide message and set up a pumping routine. An activated motion detector can flash the deck lights.