General questions and answers about Electrical Fencing.
Q. If I want to install an electric fence how should I go about finding a contractor? That is reliable, reputable and a good operator? I am concerned that the installation crew will give information about my property to criminals.
A difficult question. Look at adverts in home improvement magazines etc. Concentrate on companies that have physical addresses versus post boxes and landlines versus cell phone numbers. A company that specializes in electric fencing only, is far preferable to one that “does a bit of everything”. It is critical that the company should have their own installation teams. Many sub-contractors pick up casual labor on the morning of an installation!
Q. Is there a governing body that regulates Electric Fence installers?
Unfortunately not. Government Finalized legislation that will govern electric fence installers.
Q. Is it safe?
Yes. A properly installed electric fence in accordance with current Government Legislation is absolutely safe. The high voltage current is non-lethal because the electrical current is not continuous; it consists of pulses. Touching it, will result in a very unpleasant experience. A unit called an energizer that supplies a high voltage at generates the pulses very low amperage in short surges of power; usually around 3 milliseconds in duration. It is this millisecond pulse rate that provides the safety factor in low impedance energizers. The extremely short pulse rate prevents an electric fence from being easily shorted out and electrocuting a person or animal.
Q. What happens if there is an attempted security breach?
All EEC Secure fences come with an alarm system. Depending on the security grading of the electric fence, the alarm system is triggered from basic breaching such as: shorting of the wires, cutting of the live wire, cutting of the earth wire right up to alarm activation with any wire being touched. This is subject to make and model of the energizer and wiring circuit of the fence i.e. parallel or series. All new residential fences are wired in series with earth wire monitoring.
This is the highest security grading of any electric fence. The siren will activate in the event of any live or earth wire being cut.
Q. Can it be linked to my armed response company?
Yes, provided your alarm system radio transmitter can accommodate the additional signal. Note, the system is wired into your alarm radio transmitter and NOT to your alarm control panel. EEC Secure links your energizer to the radio transmitter remotely. This prevents the possibility of lightning damage to your radio transmitter and alarm system. EEC Secure does this in conjunction with your armed response company, as they need to zone the fence on their control panel in their control room.
Q. What are the Running Costs?
You can expect an average increase of ± R10.00 in your monthly electricity bill.
Q. What is the standard guarantee period on a domestic installation?
Very difficult question to answer, as there are so many variables. However, any reputable company worth its salt should be able to offer a minimum of 1 year on workmanship. EEC Secure is 3 years. Irrespective of the guarantee period, it is still a good idea to service your fence regularly.
Q. How can I determine whether a company can honor its guarantee periods?
Tricky question. Common sense should prevail considering the following factors:
- The average lifespan of new electric fence installers on the block is currently less than 3 months. Their price calculations are incorrect, resulting in absurdly cheap prices that cannot sustain any business. Although their intentions might be good, no money equates to no business.
- Guarantees from companies utilizing sub-contractors are not worth the paper they are written on, simply because there is no financial incentive for the subcontractor to honor any guarantee.
- Utilizing one of the “bakkie brigade” installers, well, installation quality and after-sales service cannot be big on your agenda.
- For the homeowner that is serious about quality and service: Do you’re homework.
- Use plain old fashion common sense, if it is too good to be true, it usually is!
Q. What are the maintenance implications?
Vegetation is the single biggest cause of false alarms. Cut back and trim regularly!
Q. Will touching my driveway gate result in a shock?
It shouldn’t. If your fence is installed correctly, there is NO risk of being shocked.
Q. Will it kill my cat or dog?
No. Cats are perceptive to the electromagnetic field caused by induction and as a rule avoids it. Dogs will touch the fence once and then leave it alone.
Q. How do I know which sort of energizer to choose? Are some better and more reliable than others, and have better guarantees?
Yes, some energizers are better than others and have more features. Guarantees also vary. The sales consultant should be able to advise you on the most appropriate energizer for your specific needs. It is most definitely not one size fits all.
Q. What sort of energizer will I need if I live on about a 500m², 1000m² or 2000m² stand?
The energizer size is dependent on the type of fencing cabling being used, size and layout of the property, and plant growth. All energizer outputs are governed by legislation not to exceed 9900 Volts. The difference is in the Joule rating, one of Newton’s laws, which quite simply put, is the calculation used to determine how far you can push a predetermined load over a predetermined resistance. E.g. A 4 Joule machine can “push” 9900 volt 12km over 1.6mm aluminum wire, 4km along 1.2mm galvanized braided cable and 700m over 1.2mm stainless steel cable.
Q. I have been told that I should get a “powerful” energizer. What exactly is a “Powerful” energizer?
Sales gimmick that is all it is. A 4-Joule energizer can energize 99% of all domestic installations. Yes, some energizers are better than others and have more features. Guarantees also vary. The sales consultant should be able to advise you on the most appropriate energizer for your specific needs. Again, it is most definitely not one size fits all.
Q. What about lightning strikes? Is there anything I can do about this?
Unfortunately there is nothing you can do about lightning. Some people switch off their energizers and or unplug them. It won’t help you. The reason being, the electric fence wires run straight into the energizer. In this case you are at the mercy of nature. Installing a lightning diverter kit can help, depending on the distance of the strike from your system. If the strike is close by, nothing will help. As a rule, lightning damage is covered by your building insurance.
Q. What happens when it is my turn for “load shedding” i.e. power cuts?
All energizers supplied by EEC Secure have an internal back-up battery.
Q. How many earth spikes do I need, how far apart should they be spaced and how deep should they be placed?
It is noteworthy that some companies indicate the exact number of earth spikes to be used for an installation on their quotations. Their sales consultants are clearly psychic. The number of earth spikes required cannot be guessed! The “first” earth spike should be placed as close as possible to the energizer. The placing of additional earth spikes is determined by the earth voltage measurement, which ideally should not exceed 500 Volts. This can only be measured with high voltage measuring equipment. Remember, additional earth spikes increase shock intensity. The above requirements are crucial for the effective functioning of the system. (See “How important is good earthling” Under Technical. Pending legislation prescribes a minimum of three earth spikes per domestic installation. This is quite simply because unscrupulous installers, i.e. “cheap quotes”, in a bid to save money, do not install sufficient earth spikes for the system to operate effectively. These homeowners are under the illusion that they are now secured. NOT SO. It is a statistical fact that 50% of all electric fences in South Africa cannot shock you, quite simply because they are not properly earthed. Fence new legislation. It is there to protect you, the consumer.
Q. Can I install electric fencing on top of any type of boundary or does it has to be a wall? Can it be above a hedge, or railings, or a wooden fence?
Electric fencing can be installed on just about any type of boundary and or perimeter fencing.
Q. I have seen electric fencing that is vertical, horizontal and slanted. Why this and what is the best angle bracket for electric fencing.
It is important to note that one size most definitely does not fit all! The design and type of wall will determine the type of bracket. There are different brackets for different applications. It is vital that the correct bracket be used for the relevant application.
Q. What is the difference between round bar and square tubing brackets?
Round bar is the cheapest bracket on the market. Two of the major drawbacks of round bar are; Criminals can slide the insulators apart to create an opening in order to get through and the design of the insulators does not allow for stepping up and down. Square tubing brackets are far sturdier than round bar and are suitable for stepping up and down. See photos under ”Good fencing/bad fencing”. The sales consultant should be able to advise you on the most appropriate bracket for your type of boundary wall.
Q. Most fencing seems to be black or white. Is there any other color i.e. green? I’ve been told black lasts longer and is better than white. Is this true, and if so why?
As a rule fence brackets are manufactured mainly in black or white. The reason EEC Secure advocates the use of black brackets is that white brackets will develop a black circle around the live insulators due to the bracket being charged electro statically. That is the build-up of static electricity, which attracts dust particles.
Q. I believe there are different types of wire? What are the differences and which is best?
The most common type of wire is galvanized braided cable. It is effective for most properties and a fairly good conductor of electricity. The following chart is a guideline to conductor resistance. The lower the resistance of the conductor, the better the electricity flows.
NB. Please note that this chart is based on a 4 Joule energizer and gives the recommended live wire distance for a security fence wired in series. (Longer distances can be achieved in parallel).
Type of wire Diameter Resistance (Ω/Km) Recommended live wire length
Stainless steel 1.2 mm 770 700 Meters
Braided cable 1.2 mm 330 3 Km
Aluminum wire 1.6 mm 31 8 Km
Many installers advocate the use of stainless steel wire purely because they don’t know any better. Stainless steel isNOT a good conductor of electricity. There is a massive Misconception with the general public that stainless steel wire is the best wire for electrified fencing, purely because it doesn’t rust. The fact of the matter is that nowhere in the world is stainless steel used as a conductor of electricity in any guise or form whatsoever, quite simply because pure stainless steel is NOT a conductor. Thus, the stainless steel being offered to the public by the so-called electric fence fraternity is an alloy, which defeats the object. It can only be used effectively on very small installations, and in the end will, and does, rust. If a client wants a premium installation the best conductor to use would be aluminum wire. Besides being extremely rust resistant, is it also the ONLY super conductor on the market. As a matter of interest, all Eskom’s overhead high voltage cables are aluminum. Fencing conductors of different resistance (ohms) should NEVER be used on the same Fence, as it affects the performance and affectivity of the energizer.
Q. I notice people have different numbers of wires. Why is this, and how many does the average person need?
In the past the norm was 4 or 5 wires. This was when electric fencing was still relatively unknown. Unfortunately with our current crime situation the need is for effective security, not just a token fence. The majority of the fences currently being installed are 6 + strands. If you are going to install any security measure, do it right the first time.
Q. What should the distance between brackets be? Does the distance between these brackets make any difference?
Brackets should ideally not be spaced more than 3 m apart. Because of the tensile elasticity of most metals, the further brackets are spaced apart, the easier it is to separate the wires. The distances between brackets are critical for the effectiveness of the electric fence. See photos under “Good fencing/Bad fencing”.
Q. I’ve heard the fence is better if one long continuous piece of wire is used to make the fence instead of joining wires. Is this true and why.
It is not practical to run one continuous strand of wire. What is, however, critical in domestic applications is the fact that all joints should be ferruled and or line clamped to ensure effective conductivity.
Q. Are all the wires live? Is it possible to touch one or two wires and not get any shock at all?
Not all wires on an electric fence are live. There are earth wires in between the live wires to facilitate an alarm if a perpetrator attempts to lift wires i.e. live shorting against earth. You need earth wires to ensure the shock capability of the system. The better the fence is earthed, the greater the shock. If the fence is not earthed, you cannot be shocked.
Q. Is it possible to step over an electric fence?
Yes, if the fence height is low enough and there is a stepping area on the other side of the fence. Besides having the ability to shock, an electric fence should also be a physical barrier and be designed in such a manner that it provides maximum height thereby eliminating stepping areas on the inside.
Q. Stories abound about criminals placing blankets over the fence and then climbing over. Is this true?
Absolute rubbish! No blanket can insulate you from an electrical shock. Also, with a correctly installed fence the wires will short out, activating the siren.
Q. Is it possible to cut the fence wires?
Absolutely. This is why it is critical to wire your electric fence in series, Live and Earth. Of course it is critical to install an energizer with earth monitoring capabilities. This is a phenomenal feature that, when correctly installed and wired, will activate the siren when any single strand of conductor on the fence gets cut. However, the number of installers out there that can wire the live and earth wires of any electric fence in series is very few. Again the importance of using a reputable company with fully trained staff.
Q. I know legislation prevents a charge that will kill someone. But what are the limits and how will it affect someone?
All energizer outputs are governed by legislation not to exceed 9900 Volts. A 9900 Volt shock is nasty, very nasty. However, the shock capability of the energizer is determined by its earthling. The “first” earth spike should be placed as close as possible to the energizer. The placing of additional earth spikes is determined by the earth voltage measurement, which ideally should not exceed 500 Volts. This can only be measured with high voltage measuring equipment. The above requirements are crucial for the effective functioning of the system.
Q. How long will it / should it take to install a fence around the average 1000m², 2000m² and perhaps 3000m² property?
Three days Maximum
Q. Is installing electric fencing something I can do as a DIY project?
At EEC Secure we have never come across a decent DIY installation, but it is not impossible. However, in terms of pending legislation regarding electrified fencing all current and new do-it-yourself electric fence installations will be outlawed.
Q. Are there any legalities?
Yes. All existing electric fence installations have to comply with legislation as per Government Gazette No: 23648 dated 26 July 2002.
Current Electric Fencing legislation covers the following topics:
a) Typical fence construction e.g. criteria for the placement and positioning of brackets;
b) Energizers, specification, type and application;
c) Warning signs, specification, type and application.
New / revised legislation regarding Electrified Fencing:
a) All do-it-yourself electric fence installations will be outlawed;
b) Only registered electric fence installers will be allowed to do installations;
c) Minimum requirements, e.g. minimum 3 earth spikes;*
d) A compliance certificate for fences with all new and existing fences evaluated.
e) If your fence does not meet the proposed criteria, it will either have to be upgraded to compliance, or you will be forced to remove it.
* It is a statistical fact that 50% of all electric fences in South Africa cannot shock you because they are not properly earthed. This is quite simply due to cheap, substandard installations, hence new legislation. It is there to protect you, the consumer.
Q. What is the difference between a volt, an amp and a joule?
Volt (Unit of electric potential difference)
The unit of electromotive force and electric potential difference equal to the difference between two points in a circuit carrying one ampere of current and dissipating one watt of power.
Ampere (SI unit of electric current)
The basic unit of electric current in the SI system, equal to a current that produces a force of 2×10-7 nektons per meter between two parallel conductors in a vacuum. The more amperage contained in the pulse of electricity on the fence, the more intense and severe the shock.
Joule (Unit of energy)
A joule is a unit of electric energy. It is basically a combination of how the three variables of voltage, amperage, and on time are combined to produce energy. One joule is equal to one watt of power for one second of time. In layman’s terms: The amount of energy required to push a predetermined load over A predetermined resistance. E.g. A 4 Joule machine can “push” 9900 volt 12km over 1.6mm aluminum wire, 4km along 1.2mm galvanized braided cable and 700m over 1.2mm stainless steel cable.
Q. Why does my fence lose its ability to “shock” when vegetation touches the fence?
When vegetation touches an electric fence it draws a certain amount of voltage and amperage from the fence to the earth. If a lot of vegetation touches the fence it may draw all the voltage and amperage that is being produced on the fence by the energizer. If this happens we say that the vegetation has “shorted” the fence. Other circumstances can cause an electric fence to lose voltage and amperage. If an insulator breaks and causes the electric fence wire to touch the fence post, the fence post will draw a certain amount of voltage and amperage from the fence to the post and ultimately earth. If the fence wire is rusted the flow of electricity over the fence wire will be impeded, causing less voltage and amperage to flow along the rest of the fence. Even poor “joints” in the electric fence will cause a disruption in the flow of electricity and both voltage and amperage will be lost at every splice / joint along the fence. All of the circumstances described above are commonly referred to as “fence load”.
Q. What is a continuous current fencer?
Some electric fence energizers do not cycle or pulse electricity out to the fence. Instead, they produce a continuous AC current. We call these fences “continuous current” fences. In order to make these fencers safe to use, continuous current fencers develop very low voltage and extremely low amperage. The low voltage and amperage will not cause humans or animals to “lock on” to the fence. Continuous current fencers are not UL listed. Because these fencers produce such low voltages and amperages, they do not work well on long fences, weedy fences or wet fences. They also have little effect on longhaired animals, sheep and goats.
Q. What does low impedance mean?
Low impedance fence energizers have the capability of increasing their energy output as a fence load increases. This means that as growth touch the fence and draw voltage and amperage to earth, a low impedance energizer will begin to produce higher amounts of energy or joules. These higher energy levels will overcome the voltage and current losses caused by the growth and maintain energy levels on the fence.
Q. What is a “solid state” fence energizer?
Solid State refers to a high impedance type fence energizer. High impedance fence energizers do not have the capability of increasing their output energy as fence loads increases, the way low impedance energizers do. High impedance energizer cannot overcome high levels of fence load; they “short out” when too much growth touches the fence.
Q. How long will a solar fence operate without direct sunlight?
Any fence energizer used during extended periods of cloudy weather (usually 2 weeks or longer) should be turned off to allow the battery to recharge. Normal recharging takes 3 days of good sunlight.
Q. How long should the solar battery last, and how do I know when to replace it?
Normal life of the internal battery is typically 3 to 4 years. Properly maintained batteries will last much longer. A stored fence energizer should be taken out of storage every three months to allow the sun to reach the solar panel and keep the battery fully charged. To test the battery, measure the battery voltage with a voltmeter. 12-VOLT batteries should measure 12 to 12.5 volts.
A fence energizer with a low battery should be turned off and placed in the sun for 3 days to recharge. If after this the battery voltage is not at the top of the voltage range, you should replace the battery.
Q. How important is good earthling?
Improper earthling is the cause for 90% of the problems found in an electric fence system. Here’s why… most electric fence systems are “earth ground” systems. This means that the electricity produced by an electric fence energizer must travel from the energizer’s output terminal, through the fence. A certain amount of the electricity goes through the human body and into the earth. This electricity then travels through the soil back to the earth spikes of the system. From this point the electricity travels from the earth spikes, through the ground wire, back up the fence energizer’s ground terminal, thus completing the circuit. The electricity transmitted through the soil is moving in the most direct path of least resistance back to the energizer. Electricity does not travel through certain soils very well. Moist soil with concentrations of conductive minerals is the most suitable transmitter of electricity. Recommended depth for earth spikes is 1m. The deeper it is knocked into the ground; the greater the chances of reaching subsoil moisture. It is a good idea to “water” your earth spikes once a week as this greatly increase shock intensity.
Q. My energizer is making a ticking sound, is this normal?
Yes, it is the capacitor discharging the electrical impulse to the fence.
Q. My fence clicks, is this normal?
When it rains, clicking can occur. Water is an excellent conductor and some could have accumulated on a bobbin, support stay on a corner bracket etc. During rain and or inclement weather growth is the single biggest cause of clicking. Determine where the clicking is coming from and check your fence. There could be a branch, leaf etc. on the fence causing the clicking. Switch off the energizer and remove the obstruction. In dry conditions there should be no clicking sound.