[CUWiN-Dev] Lighthning arresters

[Bill Comisky]

On Fri, 28 Oct 2005, David Young wrote:

> On Thu, Oct 27, 2005 at 11:43:48PM -0500, Kristjan Onu wrote:
>>> Our new installation is much more permanent, but there is a little
>>> work remaining---mainly sticking the new cable to the roof.
>>
>> Are you still thinking about using a lightning arrester?
>
> Yes, absolutely.
>
>> I'm a bit confused. This picture shows a schematic of a gas discharge
>> tube arrester:
>>
>> http://www.hyperlinktech.com/web/copyrighted_images/coax_lp_diagram.gif
>>
>> It shows that a ground connection is necessary. On the roof of the
>> IMC you pointed to a plastic cannister connected to Volo's equipment and
>> said it was a lightning protector, but it had no obvious ground
>> connection. I can't quite see how a lightning protector would work
>> without a ground connection.
>
> I don't remember pointing out a lightning protector on Volo's equipment.
> Anyway, there isn't one up there.
>
> Dave
>

I'm curious, has anyone out there experienced a lightning strike?  If so 
can you post-mortem the devastation for us?  I can understand the purpose 
of a lightning arrestor when the antenna is separated from the radio by a 
long length of coax, but we are mostly using a ~1 foot jumper.  In this 
case it seems like anything hitting the antenna/pole would fry the node 
regardless.  A surge supressor on the cat5 going into the building (maybe 
built into the PoE injector) seems like a necessary precaution.. 
and grounding too seems like a good idea.  Just not sure of the benefit of 
the lightning arrestor in this scenario.

bill

--
Bill Comisky
bcomisky at pobox.com