mdshunk said:
Use your browser's "find" function to search for the work "jumpers" and you can see that such a system is claimed to reduce stray current up to 40%, particularly when connected to the utility's down grounds on poles at each end of the farm. Lets the stray current flow over copper instead of through the earth of the farm.
http://www.sdbar.org/Federal/2004/2004dsd024.htm
The stray voltage issue makes farm wiring and service work very interesting. In my county alone there have been three multi million dollar lawsuits over stray voltage. One paid off 1.5 mil.
I got an emergency call out to a local dairy farm. A neighbor. A lightning strike had fried a disconnect and bulk milk tank motor. In the process of getting this farm up and running for milking time, I noticed no grounding electrode system on the barn service panel. Bonding was OK. Right outside the barn near the panel was the cow yard where the milk cows were watered and fed and put in some R&R.
I explained what was what to the farmer, and explained lightning strikes, gradiants, surges, ect. He said that service was hit twice before. I suggested ground rods but explained I was nervous about pounding them into the mud in the cow yard. Also, running a grounding electrode conductor across the flammable barn to the other side didn't exactly appeal to me either.
Mr. Farmer/customer called the POCO, and a few other farmers, and made the decision to place the ground rods in the mud yard, with the option to jerk them out if the cows seemed affected. The POCO put a new rod or two below the transformer on a pole about 100 feet away.
That was 3 or so years ago and so far no problems, and no further lightning strikes on the service equipment. I have no desire to be made a party to one of these suits or be responsible for the loss of income suffered by some hard working farmer.
I have never seen one of those circle do dads.