The thing to remember is not only are there direct physical solutions, there
are architecture considerations too. For slow speed comm, a few feet of fiber
optics on each end, even in crude form, works for isolation, but any solution
like this should also include fail-soft and fail-safe provisions, in case comm
is cut off. Even an inexpensive failure will out-cost the extra effort if it
recurs often enough. In fact, I believe California passed some
chicken-protection law, so it may result in more than just $0.20/lb next time.

Always consider the remote possibilities (and losing comm isn't so remote), and
ask what-if, then when you've got it covered, ask what if that fails... ;)

-Skip

bob.axtell@gmail.com wrote:
> While wireless is a possibility, the reality is that the world is
> jam-packed with hard-wired cabling solutions, so there IS a simpler
> solution to this. Remember that your telephone and cable company
> routes thousands of miles of wire to myriad customers. Yes, they
> sometimes sustain failures, too... nothing is immune to some types of
> damage; lightning is in that short list.
> 
> Usually PKe6-type devices are very durable, but current limiting
> resistors should be used as well. If lightning is determined to be the
> problem, there are better devices that protect by shorting the circuit
> (with an ionizing gas).
> 
> On 1/7/09, Vitaliy <spam@maksimov.org> wrote:
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