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Re: Zapping Camera Problem



"Robert Macy" <robert.a.macy@xxxxxxxxx> wrote in message
news:d06a8a5a-9401-45d4-ad31-688d9f4b40ce@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On May 25, 11:50 am, "ABLE1" <nospamh...@xxxxxxxxxxx> wrote:
> "Robert Macy" <robert.a.m...@xxxxxxxxx> wrote in message
>
> news:d9780002-8645-41b1-a51e-ae3bf622d8b1@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> On May 24, 5:23 pm, "ABLE1" <nospamh...@xxxxxxxxxxx> wrote:
>
> > "Robert Macy" <robert.a.m...@xxxxxxxxx> wrote in message
>
> >news:12025c52-47e3-45ab-84c0-28a4f42cab98@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > On May 24, 4:21 am, "ABLE1" <nospamh...@xxxxxxxxxxx> wrote:
>
> > > ...snip...
> > > There is always the thought of a Faraday Cage over the whole complex,
> > > but
> > > that just seems a bit extreme. :-)
>
> > > Les
>
> > > OH, yeah. You'll add a Faraday cage but not a few clamps. ;)
>
> > If only I had the budget.........................................
>
> ferrites are what $0.50 each? at most $1 sometimes you can get a bunch
> of 'samples' to simply try .
>
> Robert you missed my point of humor. "If only I had the budget........."
> of
> what it would take to build a Faraday Cage not for ferrites.
>
> BTW if the grounding is not right, I could be wrong but I doubt that any
> number of ferrites would fix the problem. On the other hand if the
> grounding is almost correct then ferrites would soften the effects of a
> surge. Please correct me if I am wrong in that.

"...grounding is not right." That's kind of 'by definition' it's
wrong, because it didn't work.

One can think of feerites, and those 'lumps' like the "python
swallowed the goat" appearances on computer cabling, a little like
'cutting' the cable right there, and turning the next section into a
'wireless' battery system. Well, at least at high frequency.  You only
have two things to work with here. One, a dead short, which is
extremely difficult to make. Two, an open [high impedance] which
actually is a bit easier to make.  The ferrites are like a giant RF
barrier. Theey let differential signals go through gang busters, but
won't let common mode signals through - like ''lightning' trying to
ride on your cables. The damage [if they're present] done by those
commone mode signals is that they get converted into differential
signals. And, differential signals that can be extrememly high
voltage. result arc overs, breakdown, zapping so to speak.

Sadly, EMC and ESD protection has(ve) a bit of 'magic' in them. You
can do everything 'right' [except for those necessary compromises] and
actually be worse off than if you did everything 'wrong'  Nothing like
a successful ad hoc solution to befuddle one's mind. The key is in
that phrase, necessary compromises.

If me, I'd follow either JIM's advice with a wireless system in the
remote location [note that prevents a hard wire connection between the
two buildings similar to ferrite clamps along a cable] and Rocky
Squirrel's advice who has some actual operating data. plus his 'fix'
did not sound costly, just a bit labour intensive.

========================================================
Robert,

Ok, I admit that I do not fully understand how they work or what "ferrite
clamps" can do.  As I said before I thought that they smoothed out or
blended the voltage.  However you seem to be saying that it will chop off
the higher voltage spikes so that it will not pass on down the cable.  It
would seem that I need to do more research on the little buggers.

As for going wireless.................... not sure at this time.  Need to
investigate that as well.   And going overhead just does not seem to be
viable with out any support structure available.

Thanks for input.

Les





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