[c-nsp] Surge protection on leased lines

Lamar Owen lowen at pari.edu
Fri Sep 5 12:53:05 EDT 2008


On Thursday 04 September 2008 22:52:41 Ted Mittelstaedt wrote:
> They need a sold ground and suppression such as varistors
> connected between that ground and both wires of the pair
> that the SHDSL line is on.  If you can get the specific
> code requirements for your municipality you can threaten
> to report your national telco to both the FCC and the
> local municipality if they do not install surge suppression.

[Previous poster]

> > Make sure your nid, smartbox, router are all grounded together and to
> > the electrical system ground. I suspect they are not if current is
> > flowing in and damaging your wic.

Make sure also that the grounding electrode for the telco and the grounding 
electrode for the electrical are properly and effectively bonded (as in the 
NEC Article 250 definition).

I've seen numerous instances of 'properly' installed and connected lightning 
arrestors that were not properly bonded to the electrical service ground; if 
the electrodes are even a few feet apart they can, in the lightning 
field/current gradient of a strike, easily have 15-50 thousand volts 
between 'grounds'.
-- 
Lamar Owen
Chief Information Officer
Pisgah Astronomical Research Institute
1 PARI Drive
Rosman, NC  28772
http://www.pari.edu


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