An Electric Fence consists of an open electrical circuit consisting of two arms.
The first arm is the fence connected to the power terminal of the Fence energiser. You should make sure that this is totally insulated from any other conductive material or with plastic insulators or an air gap of at least 3 cm. It does not have to loop back on itself and maybe a single line away from the energiser.
The second arm is the ground itself that is connected to the Earth terminal of the energiser by way of the earth stake or post. This then leaves an open electrical circuit.
There are different types of electric fences,
A Piggyback electric fence is mounted off the back of an existing wire or mesh fence, adding another level of security to the existing perimeter barrier. The piggyback profile is fastened to existing fence posts (e.g. pillars of a palisade fence) using rivets or screws. These are the most commonly used security electric fences.
- Wall top
Wall-top electric fences attach to the top of an existing perimeter barrier such as a masonry wall. These are the second most common type of security electric fences. The existing fence must be at least 1 1⁄2 metres (4 ft 11 in) high.
Stand-alone electric fences act as the sole perimeter barrier. They are also quite aesthetically pleasing if set up neatly. This type is normally only found at one of many levels of perimeter security around high-security establishments, meaning that to touch it someone has had to break through at least one physical barrier before this. The stand-alone fence must be at least 1 m (3 ft 3 in) away from the nearest barrier.
How Much Energy Does an Energiser use?
Very little. The energisers typically plug into a 220-volt power outlet, and they use very little energy. The energiser converts a low voltage and turns it into high voltage onto the wires. Because it pulses for a very short period every second and the fence itself is not a complete circuit, the unit uses very little energy. Typically a 1-joule unit will draw 4 Watts – compare that to a 40 watt light bulb.
What is the effect of Electric Current on an Animal?
When an animal touches the electrical wire, it causes a muscle contraction in the animal that is similar to what humans feel like a muscle cramp. With a continuous supply of current as you get with mains electricity, this results in the grabbing effect that is so dangerous as the victim is unable to release the source of the current. With the pulsing of an electric fence, this cramping is transitory and the victim is able to retreat from the source of energy.
The animal will associate this unpleasant feeling with touching the fence and will be discouraged from touching it again in the future. Thus it is not that the fence causes physical injury to the animal, but rather that it acts as a learning tool to prevent it from happening again.
Is an Electric Fence Dangerous?
No, an electric fence is not dangerous. The voltage being sent through the wires is high, but the current or amplification (amps) is very low. A 220-volt shock will hurt just as much as a 10,000-volt shock, as long as the current or amps are the same. Amps are what kills. Electric fence energisers put out high voltage (around 8,000 volts), but very low amperage or current (around 120 milliamps). This is 120-thousands of an amp.
This output is made safe in two ways, firstly by releasing the flow of electrons from the capacitor in regular pulses of high voltage but very low amperage. The amperage component of the electrical charge is greatly reduced to figures in the range of 15 – 500 milliAmps. (The majority of units operate in the 100-150 milliAmp range).
Secondly, the electrical energy pulses through the wires. This means once every second for 1/300th of a second it sends a pulse of electricity down the line. The reason for the pulsating current is that if the wires are touched and deliver a shock, whatever touches it has a chance to remove itself. If the current did not pulse (like most electrical appliances like hairdryer, radio, toaster, etc.), then whatever touched it would continue to be shocked and the muscles react to the “grabbing effect” of an electrical impulse until the power is disconnected or something pried them off.
What Happens if a Child Touches it?
If a child touches both the hot and ground wires, they will be shocked. It will hurt for approximately 10 minutes, but it will not be debilitating, leave a burn mark or kill them. Because electric fencing has low current and pulsates, it can’t kill or permanently hurt anyone. However, it is strongly advised to keep children away from an electric fence.
Benefits Of Electric Fencing
Fewer Maintenance Costs – Electric fences are composed of steel or aluminium wires that have been coated with a protective material to prevent rusting. You don’t have to worry about damage caused by precipitation, and there’s no need to paint or restain the material like you would for a wooden fence. The basic maintenance these fences require include checking for adequate voltage in the wires with a voltage meter, preventing grass and other objects from touching the fence, and checking the connections.
Ease of Installation – While electric fences should always be installed by professionals, they’re known for being easy to install, use, and maintain. Rather than incurring an extra cost of building brand new fences, electric fences can be installed parallel to or on top of your existing fence structure. Traditional fencing materials are heavy and sometimes difficult to transport, which can add to the cost and time it takes to get them installed.
Deterrence, Detection, and Delay – Electric fences deter potential intruders from accessing your property, standing in their way as a physical, intimidating barrier. While the shock these fences deliver is non-lethal, it’s enough to stop most people in their tracks, delaying their attempt to steal your assets or materials. Should someone attempt to cross the fence barrier in spite of the electric shock, high-security options such as intruder alarms will detect the intruder’s presence when they access your property. In addition to detecting security breaches, intruder alarms will also alert you to doors being opened or devices being tampered with.
Inconclusion, In an ideal world, no one will need to build a boundary or even gate their premises but that is not so. This is why we go a long way to ensure the people we love and care for are safe.
The reality is that the news of unsafe neighbourhood never seem to go away and with recent kidnappings in the country things are entirely different when the issue of home security pops up.