Installations:
Electric Fences | Intercoms | Gate Motors | CCTV | Beams / Alarms | Spikes 

We supply and install a wide range of SABS approved energisers and electric fence accessories. Our sales team will assess your specific needs taking into account the size of your property, your specifications, pricing, applicable guarantees and backup service required by you. Once our team has ascertained your requirements, they will guide you through the various brands and options available that best suit your needs and your budget.


 

ELECTRIC FENCING 101

An electric fence is a barrier that uses painful electric shocks to deter people from accessing your property via your boundary wall. An electric fence is nothing more than a glorified electrical circuit starting at point A and finishing at point Z. The length of an electric fence and the number of strands in a circuit will depend on each client’s specific needs.  An electric fence energizer is the “engine” of a fence and converts power into a brief high-voltage pulse.

An electric fence is often the first and last line of defence against an invasion via the boundary wall which if breached, can often have fatal consequences. People are often lulled into a false sense of security thinking that their electric fence is in good working order because the “good” light is flashing, or they are under the misconception that their armed response company or 24-hour guard monitors the operation of and maintains their electric fence. Ensuring your fence is at optimal operational efficiency is paramount to safeguarding your person, family and belongings.

An electric fence, like any other electrical equipment that is exposed to the elements 24-hours a day, 365 days a year – needs constant maintenance and replacement of worn and damaged component parts which is attributable to the harsh elements of the African sun and icy Highveld winters. Even a brand new electric fence can become inoperable as a result of a minor defect such as a broken wire or cracked insulator. If there is a corruption or fault at any point along the stretch of live wiring, the entire circuit will go offline. If this happens, the voltage will drop and consequently the alarm trigger will be desensitised and become inoperable.

Test-A-Fence recognised the crucial need to proactively test, maintain and service electric fences and replace worn and damaged component parts on a regular basis to ensure that the electric fence is always online and working at optimal efficiency.


COMMON INSTALLATION MISTAKES AND SHORTCUTS

Type of brackets used - There are different types of brackets each one designed to fulfil a specific function, including: vertical, horizontal and angled. It is fundamental that the correct bracket type is used for each individual installation. The design and shape of the perimeter wall will determine the type of bracket that must be used. Be careful of contractors cutting corners on bracket types in order to bring their costs down. By way of example, the round bar bracket is one of the cheaper brackets on the market. However, there are two main disadvantages when using the round bar brackets. Firstly intruders can simply push the insulators on the round bar bracket apart to create a gap in order to slide through the fence wires. Secondly, the design of the insulators on the round bar bracket do not permit for the brackets to step with the perimeter wall. Square tubing brackets are sturdier than round bar brackets and are also suitable for stepping with a perimeter wall.

Bracket spacing – Brackets should not be spaced more than 3 meters apart. The closer the brackets are spaced the more tension you get on your fence. Brackets that are spaced too far apart have less tension making it easier for intruders to push the wires apart and climb through the gap created. The correct spacing between brackets is one of the critical factors that will determine how effective your electric fence will be as a crime barrier. Be careful of contactors that skimp on the number of brackets in order to save costs and submit a “cheap quote”.

Bracket stepping – Electric fencing brackets must always step up and down with the contours of a perimeter wall so as to ensure that there are no gaps in between the fence and the wall. Such gaps will give intruders the opportunity to slip through the fence without activating the fence alarm. This is a common practise used by unscrupulous contractors in order to cut corners and save on their costs.

Number of wiring lines on the fence - In the past, when electric fencing was still a relatively new concept in the security industry, the general practice was to use brackets with 4 or 5 wires. Unfortunately with our current crime trends there is a need for a more effective deterrent, as intruders can simply step over such low fencing. Today, the majority of fences being installed are 8+ strands. Don’t be stranded with an outdated ineffective system.

Earth spikes - An earth spike is a galvanised or copper rod installed in the ground around an electric fence perimeter. An earth spike is used to earth the electric fence. The recommended depth for an earth spike is one meter. The first earth spike should be installed as close as possible to the energiser. The number of earth spikes that should be installed will depend on the length of the electric fence perimeter. Pending legislation prescribes a minimum of three earth spikes in residential installations. Additional earth spikes will increase the shock intensity of an electric fence. Ideally earth spikes should be spaced at approximately 30 meter intervals. Be careful of contractors who, in order to save costs, cut corners by not installing sufficient earth spikes for the electric fence to operate effectively. 

Electric fence earthing - Incorrect earthing is one of the major causes of problems with electric fence installations. Not all wires on an electric fence should be live. In a correct installation there will be earth wiring in between the live wiring running in series. This is necessary in order to activate an alarm if an intruder attempts to push apart the wires. If the wires are pushed apart, the alarm will only be activated if an earth wire touches a live wire. In addition, a fence has to have earth wires to ensure the shock capability of the system. The better the fence is earthed, the greater the shock intensity. If the fence is not correctly earthed it will not be an effective barrier.

Energiser size
– There is a wide range of energiser makes and models in the market. Energisers vary in size and strength. The correct size of an energiser will depend on the specifications of each installation i.e. the length and size of the electric fence and the type of wiring being used. Unscrupulous contractors often in an attempt to save on their costs install energisers that are too small for a particular property’s specifications resulting in poor voltage readings on an electric fence. Make sure that you discuss this issue with your contractor in order to ensure that the correct size energiser is installed.

The use of stainless steel wire - People tend to think that because solid stainless steel does not rust, it is the best quality wire to be used for electrified fencing. The fact is that solid stainless steel is not a good conductor of electricity. The stainless steel that is generally offered to the public is an alloy, and because it is an alloy, it will in any event eventually rust. At Test-A-Fence we only use the best quality wiring that is both, a good conductor of electricity and is durable.

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