[TowerTalk] Fwd: Connecting Tower to Ground Rod

[Keith Dutson]

The goal is to conduct as many electrons as possible, flowing from a
lightning strike, away from the tower.  IOW, spread them to a location that
can accept them into the earth.  This lowers the possibility that they will
go somewhere else, such as down a coax cable to the shack.  So, it stands to
reason that one would want to use the most conductive material possible.
Amoung conductors, gold is best, followed by silver.  However, these are not
really practical for amateur radio applications.  However, copper is likely
the best selection.  Aluminum is quite poor in comparison, but a heck of a
lot cheaper.  Galvanized steel is better, but much more difficult to work
with.

I have not read all of the posts in this thread, so I do not know if
electron density in soil/rock has been covered.  To get the most spread for
the electrons, one must plan a path that will carry the electrons away from
points with high electron density.  This means it is not good to put ground
rods close to one another.  The general rule I have seen is to chain ground
rods away from the tower base so that they are spaced at least two lengths
away from each other.  If you use 8 foot rods, space them at 16 feet.

Having said all of the above, I use just three rods at the base of my tower,
placed out from each leg.  I have had quite a few stikes over the years,
with plenty of damage to coax, rotors and antennsa.  I am going through a
re-build.  I have a roll of 2-tin solid wire (that's what they call 2 gauge
tinned wire at the electrical supply store) that will be used to connect a
series of new ground rods.  The wire will be attached using Erico Oneshot
Cadweld for 5/8 ground rods.  I also have tower leg clamps from DX
Engineering.

Keith NM5G  

-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces at contesting.com] On Behalf Of Hans
Hammarquist
Sent: Wednesday, October 09, 2013 1:54 PM
To: towertalk at contesting.com
Subject: [TowerTalk] Fwd: Connecting Tower to Ground Rod

Could you use galvanized steel wire and regular hose clamps instead? I don't
know if it is really a saving and if not, never mind.


I am using Al wires with SS hose clamps on my Al tower.


I have nine (9) ground rods, each connected with (I believe) #4 wire between
the tower and the rods.


Hans - N2JFS



-----Original Message-----
From: john <john at kk9a.com>
To: towertalk <towertalk at contesting.com>
Sent: Wed, Oct 9, 2013 2:33 pm
Subject: Re: [TowerTalk] Connecting Tower to Ground Rod


More ground rods is better, especially if you have a sizable tower.  Look at
the Polyphaser catalog for grounding suggestions.  They sell a ground strap
to tower leg clamp, which is just a hose clamp with a piece of stainless
steel spot welded to it to ensure that the copper strap does not touch the
galvanized tower.

John KK9A

To:	towertalk at contesting.com
Subject:	 Re: [TowerTalk] Connecting Tower to Ground Rod
From:	 "Roger (K8RI) on TT" <K8RI-on-TowerTalk at tm.net>
Date:	 Wed, 09 Oct 2013 10:12:20 -0400

On 10/9/2013 8:54 AM, GARY HUBER wrote:
Aluminum ground lug on the tower leg bolt, #4 or #6 solid copper to the
ground rod and a #4 or #6 to the MDP or system ground IAW with NEC. All
grounds must be bonded together.

73 ES DX,
Gary -- AB9M

-----Original Message----- From: Michael Warren
Sent: Wednesday, October 09, 2013 5:50 AM
To: towertalk at contesting.com
Subject: [TowerTalk] Connecting Tower to Ground Rod

What standardized method can I use to connect the base of a Rohn 25 to a
ground rod driven into the ground very near the base?


And I'd make that a ground system/network if there is any height to the
tower

A single ground rod doesn't provide a lot of protection. I'd consider 1 rod
about 3 feet out from each leg a minimum for a 50-60 foot tower with a
tribander on top. Check your code for requirements. They now typically
require two rods at the house entrance. We went to a 200A underground feed
about 10-12 years ago and had to replace the old, single rod with two about
3 to 5 feet apart IIRC. "I think" there are code requirements for towers as
well

73,

Roger (K8RI)

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk at contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

 
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk at contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk