> Analysis of the damage has revealed that the lines running
from main house
> to shack need to be grounded. But I have decided on a
better solution. The
> telephone line will be replaced with a new connection that
will enter the
> shack in a different location that is far from the power
entrance. The LAN
> connection will be wireless. The TV connection will be
removed and a new
> dish will be installed for the shack.
Keith, I think you are making a mistake. You should bring
all lines in at the same point, and bypass and ground them
at that point.
Moving a telephone line to the opposite end of the building
is asking for trouble.
Adding a separate small dish is OK, as long as it too enters
near the power line and all share a common ground.
> BTW, the bolt apparently hit the power lines in front of
the house, after
> the transformer. The lines enter a weatherhead on another
pole and run
> through underground conduit to the main breaker panel.
The 200 amp main
> breaker did not get tripped.
Maybe it there, but most likely not. The problems occured
because current passed through your equipment on the way to
different "grounds". From the extent of the damage when
considering the nearly total lack of protection, it doesn't
sound at all like a direct hit on your service entrance.
Lightning might hit your tower and a large portion of the
strike current will flow from the power line, since it is
such a massive ground. It may hit a power line, and current
flow from your tower ground through your equipment. It may
have hit tree down the street, or a mile away.
The wireless LAN is good because it totally eliminates a
path. The TV feed change at best won't help very much, and
if you install a dish away from the power line entrance it
can make the problem much worse than simply having a
properly installed cable follow the power line to the shack.
Moving the telco line away from the power line entrance will
certainly make things much worse.
The last thing we ever want to do is to isolate devices, and
intentionally create multiple grounds and entrance points
into a structure or equipment cluster. It is the worse
possible thing to do. This is why everyone universally
recommends common point grounds and single point entrances.
It's why telco and CATV lines enter near the utility
entrance and share the same ground.
You might consider looking at commercial installations and
rethinking your plans. The next hit could be a disaster.
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|