Electric fences work by completing an electrical circuit when an animal touches the insulated wires. A component called a power energizer converts standard AC electricity into a brief high voltage pulse.
Modern energizers emit very short pulses of high voltage that are harmless to animals and humans. It usually only takes one shock to teach an animal to respect the fence.
Animal Control
A good electric fence will not only keep animals contained but also deter predators, scavengers and trespassers. The shock is short lived and will not harm an animal unlike barbed wire which can cause severe cuts.
Modern energizers emit very brief (less than 1/300th of a second in duration), high voltage pulses down the conductor and as such pose almost no fire risk when near combustible materials. However, the ground circuit needs to be well-developed. Dry, sandy or rocky soil increases resistance so that the pulses are weaker and less effective.
The energizer, also known as the fence controller or charger must be of a size suitable for the length of the fence and for the type of animal to be controlled. It should be mounted on a support post and connected to the fence via insulated cable in plastic pipe or a single conductive wire running from the energizer to each hot (electrically charged) wire at gates, corners and the ground circuit.
Security
Electric fencing is an effective method of securing your property. It acts as a powerful deterrent, keeping out unwanted trespassers whilst providing you with peace of mind knowing that your valuable assets are safe and secure.
Electrified fences are powered by an ‘energiser’ which sends voltage down the wires in short, high-voltage pulses. If an animal or person touches a live fence the pulse completes the circuit to earth, delivering a sharp, safe but painful shock.
This type of fence can also be used for security purposes, by attaching an alarm that will activate when a trespass is detected. It can be a great option for businesses that need to ensure the safety of their employees, customers and assets. However, this kind of fencing requires regular inspections to ensure it is working correctly and is a suitable deterrent. This can include testing the voltage levels, checking for damaged wires and ensuring the grounding is in good condition.
Agricultural Use
Electric fences are often used in agriculture to contain livestock. The mild shock serves as a deterrent, helping to keep animals away from crops. This helps farmers to prevent crop damage and reduces animal-human conflict. It also helps to minimise the need for weed control and to protect buildings and structures.
A component called an energizer (also known as a fence charger) converts power into a brief high voltage pulse that travels along the bare wire. This pulse can be felt by an animal touching both the bare wire and the ground stake. A well-established grounding system is vital for the operation of electric fencing and ensures that the energizer completes an electrical circuit when it receives a pulse.
A replicated before-and-after study on oat Avena sativa crops in Namibia found that a 9.5 km long permanent electric fence malaysia reduced damage by badgers Meles meles (Wilson 1993). However, this fencing was not used to control grazing and was not able to prevent crop losses at other sites in the same village.
Horticultural Use
Electric fences are ideal for use on orchards and vineyards as they reduce damage to crops, improve grazing management and allow for the effective sub-dividing of fields. They are also ideal for keeping birds away from fruit trees and preventing pests from raiding or damaging ripening plants.
The shock only occurs when the animal completes a circuit between the positive (hot) and negative (ground) wires of the fence. It is essential that this circuit is always complete for the energiser to function correctly.
Weeds, broken or poor quality insulators and wet weather rob the fence of its full output. Adding a ground wire at the bottom of the fence helps prevent this as it allows electricity to return to the earth stake. It is a good idea to fit an energizer with an earth leakage monitor to ensure the fence is always functioning at optimum performance. The monitor will also indicate if the fence is receiving a current, and the condition of the ground system.