Re: Ground resistance tester

It sounds to me like you are looking for legal advice, not technical
advice.

With that in mind, and a lot of bad experience with lightning, I take
the attitude that the NEC establishes the minimums for protection.
After all, what can an extra ground hurt?

Last summer I had lightning rods installed on my house. I live on a
low ridge and have taken several (expensive) hits over the last few
years. They installed ground rods on two corners of the house and tied
one of them to the service ground. They also tied the Antenna tower to
the opposite ground rod. I added another ground (#6 wire) from the
Cable TV ground rod to the service ground. I also tied the Cable TV
ground to the ground rod on the invisible fence (dog containment) with
#6 wire.

With all of that I still don't have a good RF ground. I hope to put up
a vertical antenna soon and the first thing I need to do is establish
a system of radials. Of course, the first wire will be a #6 to the
service ground.

BTW, I don't understand "too far away from the service ground to be
connected."

John Ferrell W8CCW

On Sun, 4 Dec 2005 21:06:16 -0600, "AG4QC" <Joel@xxxxxxxxxxxxx>
wrote:

>Well, yes that's true.. In this case I was talking about the NEC (National
>Electrical Code).. Sort of a basic electrical question, from a ham radio
>prospective. They put up a Satellite Internet dish on my roof and it was
>too far away from the 'Service' protective ground so it's not grounded. So I
>ran my own bonding ground wire to tie it into the rest of my single point
>grounding system. It started me wondering just how affective all these
>ground rods were, even though they are all bonded together. So that started
>me looking around for a way to measure the resistance to ground, as I figure
>the less the better. Of course, in this case I am talking about 'protective'
>ground as required in the NEC handbook. The electricians around here eyes
>glaze over when I ask about the 25 ohm or less requirement.
>
>So I figured maybe someone on here had experience measuring the required
>ground.. It would be my luck the house would take a minor lightning hit and
>the Insurance company would try to weasel out of there responsibilities by
>saying the ground didn't meet the NEC requirements not to mention I rather
>not have issues. While unlikely, I hear all sorts of horror stories on how
>they are trying to disallow claims for all sorts of reasons after Katrina.
>
>Joe AG4QC
>
>"Ivan Makarov" <miv@xxxxxxxxxxx> wrote in message
>news:YcWdnWUOpY4hPA7eRVn-uQ@xxxxxxxxxxxxx
>> Apparently Joe is talking about contact resistance between a grounding rod
>> and the soil. Is that correct, Joe? I also saw those ground rod clamp
>> testers in the Inet, and is still puzzled how they claim accuracy down to
>> 0.01 Ohm.
>>
>> Thks,
>> Ivan
>>
>>
>
John Ferrell W8CCW
.

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