The Digital age brought change to the auto industry and is continuing to evolve in more advance levels. Gone are the days of the “Backyard Mechanic” tuning a four-barrel carburetor. Today’s mechanics have been replaced by technicians. This newer breed of repair people spends more time on the computer keys than turning a wrench.

This same technical wave has also reached the recreational vehicle in a big way. Unlike most automobiles, a large class A coach requires miles of copper wire carrying power to the chassis components and to the many appliances, lighting, and feature packed gadgetry. So much wire would add significant weight to the unit. In addition, given the number of individual circuits needed, troubleshooting an electrical issue could present a challenge.

But, thanks to the digital age, more and more RV’s are employing multiplex technology, logic boards and micro relays within their builds. A simple explanation of multiplexing uses perhaps only one wire to do the job of, say, six. To accomplish this it uses a logic board that sends varied voltage valves in both forward and reverse. A logic board located at the target decodes these signals and activates the appropriate function. For those familiar with the “Smart Wheel” found on many diesel class A coaches, you will appreciate the many button choices available. These are all supported by only three or four light gauge wires.

While the multiplex system cuts the quantity of wires required, it also reduces the gauge, or weight. The much smaller wire gauge sends only the signal to the targeted relay from which it uses a single heavy busbar to power any or all.

For complex electrical circuits involving all the chassis and body functions and features, digital systems are far easier to troubleshoot. Generally, a computer can locate and determine the problem in minutes. This can save downtime, service labour, and have your RV back on the road sooner.

Well, while it may seem quite boring, it all adds up to a better product that hopefully will deliver years of good service.

Peter Mercer – With Less Wire

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  1. Peter Mercer

    Thank you, and I’m glad you found the piece of interest. Solar panels on RV’s are a great benefit. I recently had my unit in outside storage without the availability of shore power. The 3 solar panels maintained all the batteries at 100% steadily for weeks. Thanks for taking the time to comment.

  2. Nice one Peter. New technology, more benefits for us – the regular people. More competition, lower prices. Can you tell something about the Solar panels for RVs. The ECO trend is going crazy these days 🙂 Cheers!