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Re: CAT5 surge/lightning strike protection recommendations?


From: David Lesher <wb8foz () nrk com>
Date: Tue, 13 Sep 2005 22:10:41 -0400 (EDT)


Speaking on Deep Background, the Press Secretary whispered:



I have a bunch of cat5 buried about 1 ft below the surface connecting multiple
buildings on a campus (short runs) and lightning strikes nearby have caused
surges along one or more of the cables and burnt out switch ports. I would
like to protect the switch ports -- there seem to be lots of products on the
market.

Anyone have recommendations 

A) Don't.

B) Don't

C)...

Surge protectors can not protect you from ground differential issues.

Your answer is

1) Pull fiber with that CAT5 pullrope.

2) If you REALLY, REALLY can't....

Put a fiber transceiver in building A. At least 10 foot away,
put in a 2nd transceiver and connect THAT to the CAT5 going to
building B.  Connect A & B wallwarts to different breakers, with
surge protectors....and stock spares.o

{Extra help; power B from a small hospital-grade isolation
transformer -- low leakage, hi breakdown voltage.}

Hopefully, you'll merely lose transceivers & wallwarts on the
B-side, with nothing in building B being zorched. 




-- 
A host is a host from coast to coast.................wb8foz () nrk com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433


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