Computers are taking over!

drewpster

Commander
Joined
Oct 17, 2006
Messages
2,059
I just finished some training on multiplexing. I know we deal mainly in older boats here, and that is just how I like it. But the times they are a changin'. I had heard that there are some boat manufacturers that are moving the same direction as many other industries. Multiplex electrical systems are coming! It is a whole new way of thinking in terms of electrical systems that enables all the functions of the system to work through a single pair of wires! Yes, that's right, all the functions, lights, gauges, pumps, engine controls, everything, through two wires. This reduces the amount of wiring significantly throughout the vessel.
It works through the use of computers which control circuits via inputs from a network. Just like your computer at home. I light for instance will turn on with a switch that is connected to a digital network. When the switch is turned on the computer "sees" the signal from that switch and powers the light on. The advantage of this is that the pair of wires that connects the light switch to the light, via the computer, is the same pair of wires that connects the bilge pump switch to its pump. So only a single pair of wires is needed at the control panel. The system also allows all the electrical functions to be programmed into a computer. Lights can be made to fade on and off, flash in an emergency, change to red automatically at night, and just about any other thing a light can be made to do. An indicator on the dash can also let you know if a light bulb is blown or if corrosion is causing too much resistance in a given circuit. And that is just a light!
All the control and indicator panels can be arranged how ever you like. Want to be able to turn on a deck light from the cabin? Easy, just remove the deck light switch from the panel on the deck and plug in to the panel in your cabin. That specific switch controls that specific function. So when the deck light switch is toggled on in the cabin the computer knows to turn the deck lights on. Cool.
It may seem to be overcomplicating things by using this system. However after you understand how the system works you find that it actually simplifies things. Another cool thing about this system is that it can be designed to do just about anything that you can program a computer to do. So the functions and accessories that can be offered using the system is just about infinite. It can also be designed so that upgrades can be easily flashed into the computers if you want a new option later on. Things like LORAN, radar, sonar, fish finders, GPS, Autopilots, can all be integrated into the system. Want your radar to automatically come on, a warning to wake you up, and your cabin lights to come on when a storm is near? Easy, add a panel and a screen to the cabin, plug it in to the network, program the computer and your done! Its all possible.
The first thing I asked in class is what would happen if this simple pair of wires gets damaged, thinking of course the whole system is messed up. The instructor explained that the control computers can have a thousands of contingencies programmed into them. So if communication breaks down in part of the network the computer will activate the contingency. For example in the event a network wire (datalink) gets damaged controlling a deck light the computer will turn on a simple indicator letting the captain know. Or in the event of a lightening strike that takes out a main computer emergency contingencies are automatically put into place controlling necessary systems. Things like engine, steering, bilge pumps, fire abetment, will be in protected circuits or even have manual overrides to insure the boat gets home. The safety in the system comes in the fact that the computers can contain literally thousands of contingencies in the event of failures. Also the most important systems, like the ones I mentioned before, can be designed to have the same safeties that they have always had. Like sailors always say "No matter what hell descends, we have wind and sail".:)
With the cost of fuel always going up and EPA guidelines getting more strict we are going to find that computers and these types of systems are going to become more prevalent in the future. It may seem complicated but D.I.Y. folks like us are still going to be able to work on these boats. You already have the most important tool you will need right in front of you, your computer. The trick will be changing your way of thinking about electrical systems. Its coming folks! Sooner than you think.:eek:
 

dchris

Petty Officer 2nd Class
Joined
Jun 10, 2007
Messages
135
Re: Computers are taking over!

You are very right on this. Have you looked into microchip.com. They give their programming tools away at a low price in hopes that people will buy their chips. They have some very low cost chips that can preform many of the tasks you present.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,620
Re: Computers are taking over!

Welcome to the 21st century :)

Computer control has been is use in the high-end market for sometime know. As the cost has come down production builders are using more and more system of these types of systems on their boat. All of the major motor manufactures now offer some sort of an electronic control and monitoring package with their motors.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Computers are taking over!

While multiplexing is new to boats, it is certainly not new technology. The Boeing 747 for example, was placed in service in 1969 and used a great deal of multiplexing. The original 16 channel audio system was multiplexed with the pilot and flight attendant intercom systems which placed the acoustic tube audio transducers at each seat. Miles of wire were eliminated using that system. Multiplexing has been common technology in the Telecom and general communication fields for years. Boating is only about 40 years too late adopting the technology -- but then we didn't have a need for it back then since gps, locators, radar, radios, electronically controlled engines and other electronic gadgets were not available for the general boating public.
 

fdmsiv

Petty Officer 1st Class
Joined
Mar 2, 2008
Messages
283
Re: Computers are taking over!

I first found out about this technology when I built a model train set about 5 yrs ago. They called the system DCC I think.

Instead of only being able to control 1 locomotive at a time, you can now control multiple locos at once. The control box would speak to each loco through a chip attached to the motor. The chip would read signal sent through tracks.

This system simplified the wiring immensely and made the whole experience more enjoyable
 
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