Eighty percent of electric fence problems can be traced to fault grounding systems. For an animal to receive a shock it must complete a circuit.
Moist soil is a good conductor of electricity.
Therefore, electric fences on irrigated pastures rarely require ground wires. The grounding system for an electric fence is a little like a radio antenna. With a radio, the bigger the antenna, the better the reception. Likewise, your electric fence energizer requires a large grounding system to collect enough electrons from the soil to complete a powerful circuit. A minimum of three ground rods should be used for each energizer.