Jim
What would you recommend for routing bonding points if the shack is 75'
from the power panel and the tower is another 50' farther from the
shack (i.e. 125' from the power panel). Bonding to home's ground system,
if I follow the proposed trail below I would have to run the cables 125'
from the tower to the home ground point at the panel and then 75' back
to shack? Should I drive a 2nd ground near the shack and tie that back
to home ground and then run the radio cabling through that 2nd ground
point as outlined below?
Of the 11 houses I have owned over the years two of them were basically
configured as such.My current set up here in Florida the lightning
capital of the world is even more convoluted from this perspective with
the shack in a stand alone building 100' from the house ( and main power
panel) and and the tower another 35' beyond that.
Not to get into too much detail in the end I have three 10' ground rods
at the tower and two more 10' rods at the shack cable entry. The
previous owners who built the house did not install a separate power
panel in the out building but rather ran four separate lines
(underground ) to the outbuilding (3-120V and 1-240V) from the main
panel. Lately I have been looking at this with a jaundiced eye and
considering that I likely would be better served to have a single 240V
line to the out building and a separate power panel installed at the
outbuilding then connect all the outbuilding power to that panel. Not
sure why they weren't required to do that to begin with ...but Florida
is known for a lot of fly by the seat of your pants contractors...since
there is a lot of boom building.
All that said I still disconnect the antenna feed, the rotor cable and
the Stepp-IR control cable and go hide in the house when it starts to
spark outside ...8^). I have lots of personal stories to support that !!!
Dave
NR1DX
On 3/23/2021 3:48 AM, Jim Brown wrote:
On 3/23/2021 12:11 AM, Ron Hylton via TowerTalk wrote:
I'm contemplating the best route for the coax and control cables from
a new tower to my single-point ground and shack. The easiest and
shortest way to get the cables to my entry point is by running them
through the crawl space of my house (diagonal across the span of the
house), and then back outside to the entry point.
My concern about doing this is bringing the cables into the house
(albeit the crawl space) without lightning protection. Certainly I
could install protection at the base of this tower for all lines
before making the run under the house, but this doesn't really adhere
to the single point ground notion.
Trying to run the cables underground in conduit to the entry point
would be quite a hassle for multiple reasons - a retaining wall in
the path, sprinkler system, septic drain field, etc.
One other note - I'm in the Pacific Northwest, so lightning is not a
real common occurrence, but I still want to do this the safe and
right way.
Ward Silver and I are currently working our way through this sort of
issue for the 2nd edition of his ARRL book and Grounding and Bonding.
My current thinking is that, for lightning protection, the safest
solution is to bring cables to ground level below the shack and bond
their shields to your home's ground system there, then extend them to
your shack entry point where coax lightning protectors are installed,
with that panel bonded with a direct run to your home ground system.
That entry point and the protectors should ideally be in a wall plate
"pass through" as close as practical to your operating desk.
The logic for protectors at the entry panel very close to your radios
is that lightning-induced currents in coax shields will induce a
differential voltage inside the coax, which can fry your rigs.
Protectors operate by shorting center to shield, and that short should
be as close as practical to the rigs.
73, Jim K9YC
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
--
Dave Manuals@ArtekManuals.com www.ArtekManuals.com
--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|