[TowerTalk] Grounding towers

[Jim Lux]

On 3/24/12 6:43 AM, Gregg Seidl wrote:
  I recently built a
> new shack in my basement and redid the grounding of it. I have 4
> ground rods pounded into the ground about 7 feet and have my station
> ground connected to them. I have the ground rods connected in series
> and then I connected my station ground to the line running between
> them. At the end of the ground chain sits one of my towers, 85 feet
> of Rohn 45. This tower is connected to ground via a ground rod. I
> thought I'd run the ground line further and connect my station ground
> to that tower as well. Then I got to thinking if it would help to
> connect the other towers as well. Is it practice to connect them in
> series?

You're presumably talking about "electrical safety ground" (as opposed 
to an RF ground..) and to a lesser extent a lightning dissipation 
ground.   Yes, you want them bonded, and whether series or star doesn't 
make much difference at 60Hz or DC.

  That would require less wire then paralel (sp). Also can one
> connect the power feed ground to this same ground?

Yes. bond it.  the usual NEC Art 250 stuff.. AWG 6 wire, listed 
compression clamps or exothermic bonding.


  I don't want to
> have a better ground then the Public Service and have all those
> issues like we did when I had a dairy farm and had some issues with
> stray voltage.

That's a different issue, and you still need to have all grounds in a 
given structure bonded together.


I am also on sort of a budget and don't want to spend
> tons of money on copper that isn't really going to do any good. I'm
> trying to find a happy meduim of protection,safety and improved radio
> preformance via a better ground with less noise pickup. Any ideas
> would be great and reasons why would be fantastic. Gregg K9KL

Grounding generally doesn't do anything for noise or RF performance.  In 
fact, if it does, that implies that your electrical system (e.g. the 
safety ground) is part of your antenna, and that's not good.  See  the 
Jim Brown (K9YC) writeup on RFI and related issues 
http://www.audiosystemsgroup.com/RFI-Ham.pdf

other useful stuff at:
http://www.audiosystemsgroup.com/publish.htm

You might also go to http://www.mikeholt.com/ and hunt around for the 
free "low voltage handbook" which talks about grounding antennas and 
such and has the relevant parts of the electrical code.  The link within 
the site moves around.  You might just be able to google or bing "Mike 
Holt Low Voltage Grounding"

http://www.lerc.org/pdf/LowVoltBook.pdf at 
http://www.lerc.org/pdf_downloads.php was one place..

Be aware that this book is a few years old, and the NEC is revised every 
5 years.  Your local jurisdiction might not be using the latest code. 
However, if you implement the latest code, it's unlikely you'll be 
noncompliant with an older version.


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