Electric fencing uses pulses of electrical energy to create a psychological barrier that trains animals to avoid the Fence Building. The fence delivers a brief, high-voltage, low-amperage shock when an animal touches it, teaching the animal to respect the boundary. Electric fencing is widely used for rotational grazing, temporary paddocks, predator exclusion, and perimeter security. It is generally more economical than conventional fencing for large areas.
The energizer (fence charger) is the power source. It converts mains power, battery, or solar energy into high-voltage pulses of 4,000 to 10,000 volts lasting 0.0003 seconds, delivered at intervals of approximately 1 second. Solar-powered energizers are suitable for remote paddocks and are rated in joules of output energy. A 0.5 joule energizer powers up to 3 kilometers of fence, while a 5 joule unit covers 15 kilometers.
Grounding is critical for effective fence operation. The ground rod system consists of 2 to 3 galvanized rods, each 1.2 meters (4 feet) long, driven into moist soil and connected to the energizer's ground terminal. In dry soil conditions, additional ground rods or a longer ground system is needed. The fence wire is connected to the energizer's positive terminal.
High-tensile steel wire, typically 12.5 or 14 gauge, is used for permanent perimeter fences. It is spring-tensioned to 120 to 180 kilograms (270 to 400 pounds) and does not sag significantly over time. Aluminum wire is lighter and more conductive but less durable. Polytape and polywire combine stainless steel filaments with polyethylene strands for visible temporary fencing used in rotational grazing. Polytape is available in widths of 12, 20, and 40 millimeters.
Pasture rotation depends on portable electric fencing to subdivide pastures into paddocks. The netting type, which combines vertical and horizontal electrified strands in a rollable mesh, is effective for sheep, goats, and poultry. A single strand at nose height is sufficient for cattle in temporary divisions. Predator fencing uses a combination of electrified wires at staggered heights with a ground wire between each hot wire to prevent climbing or digging.