Ground Rods and Ground Rod Clamps
Ground rods or other grounding arrangements are an essential part of any electric horse fence. In order to administer a shock, the current generated by the electric fence charger, sent out to the fence, and passed through a target animal into the ground, needs to complete the circuit by passing through moist ground to a ground rod, from whence it can go up the ground rod, into a wire attached to the ground rod, through the wire (which does not need to be insulated), and over to the ground terminal on the charger. Within this context, the electric fence will fail if the ground rod is not in reasonably good contact with moist soil (neither dry ground nor frozen ground will conduct electricity), and indeed this is a leading cause of electric fence failure. So long as the soil is generally moist in the area where the horses’ feet are located when they touch the fence, the horse fence may need only a single 6 or 8 foot ground rod. If moisture is generally present but sometimes marginal, or if the fence is over a quarter-mile long, use several ground rods hooked up together and spaced at least 10 feet away from one another. One also needs to know that corrosion can build up on the surface of a ground rod, to a point where a new rod may need to be set in every couple of years. Beyond that, if the soil sometimes gets bone dry, or if it freezes hard in winter to a point where it is unlikely to carry a charge, it becomes necessary to supplement the ground rod with other measures–the most common step being to alternate active and neutral (inactive) conductors on the fence and to tie the neutral conductors into the grounding system (by running a wire from these conductors over to the ground rod or over to the ground terminal on the charger). That way an animal touching both an active and neutral conductor at the same time will get a shock regardless of the condition of the soil.