Hi Ed,
Your post raises a number of questions for me. There isn't
enough information to make sense of your findings. So that we
can interperet your results, can you answer the following
questions for us?
1. How did you make this measurement?
2. What kind of measuring device was used?
3. How was the connection to the center of the base made?
4. What is the measured electrode connection resistance to earth
for the rod?
5. Does the concrete contact the earth directly or does the hole
have some kind of liner (wood form, plastic sheet, etc.)?
6. What kind of earth are we talking about?
7. Did you make a similar measurement between two of the
(otherwise unconnected) ground rods?
73, Eric N7CL
To: <towertalk@contesting.com>
>Date: Wed, 14 Oct 1998 03:14:49 -0400
>From: "Edward W. Sleight" <k4sb@mindspring.com>
>
>OK guys, I happen to be in a very unique position. The base was
>poured for my new 89 footer yesterday. It's 5.5 x 6 x 7.5
>feet. This evening, I measured the resistance between one of the
>ground rods (4) and the center of the base. At that time, the
>concrete was 36 hours old. The resistance was 1.47 Meg Ohms.
>
>I believe keeping the exposed section as wet as possible
>strengthens the concrete, so earlier today, I flooded the top
>with 2" of water.
>
>I'll flood it again tomorrow and repeat the test ( before and
>after ) At that resistance, it won't even blow a .1 amp fuse.
>
>73
>
>Ed
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