BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
STAFIX
TM
ELECTRIC FENCE AND SECURITY CENTRES
STAFIX
TM
BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
ELECTRIC FENCING FOR GAME CONTROL Course facilitator M.J. Williamson INTRODUCTION There is nothing new about using electricity to control animals. For over seventy years farmers have been using electric fences to control their livestock and as long ago as 1952 records show that Uganda state forestry department used electric fences to protect young seedlings from being damaged by African wildlife. However. the mechanical "tick tock high internal impedance type energisers used back then were simply unable overcome much competition from vegetation and thus could only power relatively short lengths of fence line. The technological advancements in solid state electronics during the 1970's resulted in the development of the modern. low internal impedance. high powered energisers in use today. These modern energisers are capable of powering many Kilometers of multi stand electric fencing and the electric fence has now become a truly effective management tool that is being used successfully around the world to control all species of wildlife. Today very few conservation organisations do not incorporate electric fencing in their wildlife management programs. However, despite the successes achieved in Africa and elsewhere around the world, electric fencing still has its detractors. While most people swear by it there are still a few who swear at it. (And that's not just after they've taken a jolt - anyone is inclined to do that) So why these contradictory results? The answer is simple, those who swear by it understand and apply. the basic principles of electric fencing when erecting their electric fences. Finally. while economics will obviously be an important consideration when planning any electric fencing project, guard against being too thrifty and of basing major decisions on price considerations alone. Remember. "goedkoop is duurkoop.. or to put it more appropriately, when dealing with wildlife. "if you pay peanuts you'll get (or lose) monkeys." GOLDEN RULES OF ELECTRIC FENCING *When it comes to the electrification of any game fence there are some basic golden rules one must observe. These Golden Rules are :* * * * * * * * * * * * * *
Plan your layout with the future in mind Understand and apply the basic principles of electric fencing . Pay particular attention to earthing . Use only high powered energisers Leave the energiser "ON" at all times (Except when working on the fence or during bad electrical storms) Position your energiser in the centre of your fence line. Use the correct fence design for the animal intend to control. Connect the live wires in parallel. Always use line clamps when joining wires. Use only hot dipped galvanised metal accessories (prevents electrolysis). Install cut-out switches to facilitate fault finding and have a volt meter. Have a fence hygiene / maintenance programme. (Implement it) Animals need time and space to become accustomed to an electric fence. Fire up your fence line as construction progresses.
Apply these golden rules and you will enjoy the full benefits of electrifying your reserve. Also remember, an electric fence is a psychological fear barrier so it is very important that all animals receive a good shock the first time they make contact with the electric fence.
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
DEFINITIONS: ELECTRICAL TERMS These definitions of electrical terms are frequently used in association with electrical fencing. While all the definitions are correct in content, details necessary to make the definition rigorous have frequently been omitted for clarity. Electricity:
A flow of electrons around a circuit.
Electric Charge: This is the quantity of electricity -literally the number of electrons. Charge is measured in coulombs. Voltage:
The electrical pressure that forces electrons around a circuit. A voltage is necessary before any current can flow.
Current:
The rate at which electrons are flowing in a circuit. Current is measured in amperes, but this is commonly shortened to amps.
Power:
Power in electrical form has the same sense as power from an engine. It is the ability to do work at a certain rate and is measured in watts. Power is voltage multiplied by current.
Energy:
Electrical energy is the ability to provide power for a period of time. It is measured in joules, a joule being one watt of power developed for one second. Similarly 1000 watts for one hour is a kilowatt-hour or one unit, the basis of local authority power charges. One kilowatt-hour is equivalent to 3,6 million joules.
Conductor:
A material through which electrons will readily flow (all metals are conductors).
Insulator:
A material that strongly resists the flow of electrons through it. Circuit: A conducting path around which electrons may flow.
Circuit:
A conducting path around which electrons may flow.
Resistance:
Opposition by an electric circuit to the flow of electrons. Whenever a current flows in a resistor, energy is lost in the form of heat. Resistance is measured in ohms.
Inductance:
Opposition by a circuit to rapid changes in electric current. Energy is not lost but stored in an inductor.
Capacitance:
Opposition by a circuit to slow changes in electric current. Energy is not lost but is stored in a capacitor.
Impedance:
Opposition by a circuit to current flow due to the effects of resistance, inductance and capacitance. Whenever a current flows through an impedance, there is a voltage developed across it. If this impedance is the effective internal impedance of an electric fence energiser, or the impedance of an earth or lead out wire, the voltage developed across it would be considered to be a loss.
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
COMPARING COMPARING ENERGISERS ENERGISERS AND AND FENCE FENCE LINES LINES WITH WITH PUMPS PUMPS AND AND WATER WATER
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WIRING CONFIGURATIONS
Parallel Wired
Fence Line Resistance of 2.24mm H.S.S. galvanised wire is 40 ? per Km.
Resistance of one Km of four strand fence wired in parallel will be: 1 R =
1 +
R
1
1
+
+
R
R
4
R
1 R = 10
= 40
10
Series Wired
Fence Line
MONITOR Resistance of one Km of four strand fence wired in series will be: R =
R
R
R
R
R = (40 + 40 + 40 + 40) R = 160
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
HOW DOES AN ELECTRIC FENCE WORK A Stafix electric fencing system controls animals by giving them a short, sharp, powerful yet safe, shock that is sufficiently memorable that they will not forget it.
Low Power, little into memory box.
High Power, plenty into memory box.
When an animal makes contact between the live wire of the fence and the ground the circuit is completed and a shock received
REMEMBER An electric fence is both a physical and a psychological barrier All animals need to be trained to respect electric fences
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AN ELECTRIC FENCE SYSTEM An electric fence system is made up of three components
1 THE ENERGIZER
2 THE EARTHING SYSTEM
3 THE FENCE LINE
If any one, or more, of these components is faulty or defective, then the whole system will be defective.
Linking the three components of an electric fence together provides the circuit through which the current will flow
Energiser
Fence Line
Earthing System
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Circuit of an Electric Fence All Live / Earth Wire Configuration (applied in moist ground conditions)
Stafix Energiser
Earth Stakes
2m 3m
3m
Circuit relies on good current flow through the moist ground
The circuit is closed between the live wire and the ground when the animal makes contact with live wires
Live / Earth Wire return Configuration (applied in dry ground conditions)
Stafix Energiser Current flow in fence line
Current returns via earth return wire Earth Stakes
2m 3m
3m
Poor current flow in dry ground
The animal closes the circuit between the live and earth return wire
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Circuit of an Electric Fence All Live Wire Configuration (applied in moist ground conditions)
The circuit is closed between the live wire and the ground when the animal makes contact with the live wire
Offset bracket Existing fence line Stafix energiser
Offset bracket
2m 3m
3m
Earth Stakes
Live / Earth Wire return Configuration (applied in dry ground conditions)
The animal closes the circuit between the live and earth return wire
B&B Offset bracket
Current flow in fence line
Current returns via earth return wire
Stafix energiser
Existing fence line
B&B Offset bracket
2m 3m
Poor current flow in dry ground
3m
Earth stakes
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EARTHING EARTHING EARTHING EARTHING (GROUNDING)
Earthing is the most important component of an electric fencing system
Over 80% of electric fencing problems can be attributed to poor earthing.
WHY IS AN EARTHING SYSTEM NECESSARY? For an electric fence to be effective the circuit must be completed. When an animal touches the fence wire the circuit is completed (closed) through to the ground, or to the earth return wires, and the current flows back, via the earth pegs, to the energizer
(GROUNDING) EARTHING
EARTHING
EARTHING Electron flow in damp areas, in an all live system.
EARTHING
Electron flow in earth return wire fence as used in dry areas.
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DO'S DO'S AND AND DON'TS DON'TS OF OF EARTHING EARTHING DO *
Use at least 3 galvanised earth stakes each at least 2M long.
*
Drive the earth stakes into the ground at least 3M apart.
*
Connect the earth stakes together using a single length of insulated undergate cable .
*
Clamp the cable securely to the earth stakes
*
Install the earth stakes in moist or damp soil.
*
Close to the building or along the fence line for protection
*
At least l0M away from any mains power supply, earth stakes, underground telephone cables, power cable or water pipe.
DON'T *
Connect two or more energizers to the same earth peg.
*
Use copper earth stakes ( electrolysis).
*
Allow any part of the earth system to touch a building i.e. bare wires.
*
Connect the energizer earth to E.S.C.O.M. or Telkom earth's.
*
Connect the earth system to water mains.
LIVE LIVE EARTH LIVE EARTH
2m 3m
3m
1km Intervals (0.6 Miles)
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TESTING TESTING THE THE FENCE FENCE EARTH EARTH RETURN RETURN
*
A poor or inefficient earth system will restrict the flow of electrons or current around the circuit.
*
On a clean well-insulated fence there is very little current flow so in order to test the earth it is necessary to create current flow creating a short or leakage path.
*
Bring the fence line voltage down to 2K v or less by placing several steel stakes between the live wire of the fence and the ground, at least 100M away from the earth system.
*
Drive a galvanised earth state at least a meter into the ground and at least a meter away from the nearest earth stake of the fence system Then using a Digital Volt Meter measure the voltage between this installed earth peg and the nearest earth peg attached to the energiser earth system.
*
Ideally there should be no reading on the volt meter. A reading of up to 200 volts, provided the fence is shorted to below 2000volts, is acceptable. If the reading is above 200 volts increase the number and quality of the earth pegs.
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TESTING AN EARTH WIRE RETURN SYSTEM This should be done as close to the end of the fence line as possible. Install an independent earth stake at least 1.3M into damp soil. Then, using a D .V .M. measure the voltage between the live and tbe earth wires, and then between the live wire and the independent earth. The voltage on the latter measurement should not be more than 200 volts greater than the voltage between the earth and the live wires. If the voltage is higher than 200 volts then the earth return wire must be checked for loose connections and / or more earth stakes must be installed along the fence line. These additional stakes must be coupled to the earth return wire. Remember, surveys have shown that over 80% of electric fencing systems suffer from inadequate earthing. So, spend a little extra time on this important aspect of your electric fence and enjoy many years of trouble free fencing TEST YOUR EARTH STAKES ANNUALLY
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INDUCTION Induction is a phenomenon associated with High Voltage wires whereby a small current is transmitted through the atmosphere to adjacent neutral wires Induction can be detected in a item by using a volt meter, or when the item is touched, one can feel a small shock Induced voltage can be detected on :Conventional fences carrying offset or lead-out wires The wire between the strain insulator and the strainer post Metal gates Milking parlor railing Showers Induction is linked to poor earthing and can be prevented or eliminated by earthing the offending item Induction does not detract from the voltage on the fence line.
6000v
600v
Earthing Wire
500v 800v Offset Wire 600v
1000v 800v 500v
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LIGHTNING PROTECTION
Lightning
Energiser
2m 3m
3m
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LIGHTNING LIGHTNING PROTECTION PROTECTION (LIGHTNING (LIGHTNING DIVERTER) DIVERTER) Cut-out Switch Joint Clamps 600mm Energiser Lightning Divertor Insulated Cable
Insulator
3m+
Choke
20m+
2m 3m
Earth Rods
3m
2m 3m
3m
Earth Rods
Using a lightning diverter does not guarantee complete protection and it will not protect the energiser from a direct strike or from surges up the power supply line. In a storm disconnect the energiser from the fence line and unplug it from the power source. On long fence lines, and in areas where lightning is a major problem, installing additional lightning diverters along the fence line is recommended.
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WHAT WHAT IS IS AN AN ENERGIZER ENERGIZER ?? An energizer is an "electron pump" that converts an A.C. or D.C. electric power source into high voltage pulsed energy The power source can be either 220 Volt mains power or a 12 Volt battery supply. . When comparing an energizer to a water pump: .Voltage = Pressure Amps = Flow ( volume ) The power output of an energizer is measured in Joules. The number on a Stafix energizer gives the output Joule capability of the energizer. This measurement can be used to compare energizers and can be likened to Horsepower of an engine. The cyclic wave shape of the Stafix energiser range ensures that maximum power is maintained on the fence line at all times. INSTALLATION OF AN ENERGIZER
The ideal location of an energizer is at the center of the fencing system. Attach mains powered energizers securely to an internal wall: Out of the reach of children Away from corrosive chemicals Close to the power point Connect the fence to the red terminal of the energizer using double . insulated 2.5 mm cable ( or 2 to 3 lengths of ordinary 2.24 mm underrate cable.) Connect the earth system to the green terminal.
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CHOOSING CHOOSING AN AN ENERGISER! ENERGISER! WHAT WHAT TO TO LOOK LOOK FOR FOR IN IN AN AN ENERGISER ENERGISER A well known brand One that meets the International Standards of Compliance Modular construction for ease of servicing That there is back -up service and that spares are available WHAT TYPE AND SIZE ENERGISER ? This can be quite a difficult decision as there is as much variety within a single brand as there is between i the many brands available on the market. Choice will be influenced by :Power source -is mains power available ?- if not you will have to use a battery powered unit possibly with solar panel back-up Length and type of fence line to be powered -The longer the fence line the bigger the energiser. The type of animal to be controlled - Sheep require more power to control them than cattle (insulation of the wool) Wildlife also should be controlled using bigger energisers. Likely competition from vegetation -Midlands of Natal experiences heavy spring flush, and grass on the fence lines can cause a problem HOW DOES ONE DETERMINE THE SIZE OF AN ENERGISER ? , This can also be quite difficult to determine as different manufactures use different criteria to promote their energiser's capabilities. One must be sure one is comparing apples with apples when comparing claims made by different manufactures. Compare :1) Voltage output -especially under different loads 2) Joule Rating -Stored or output joules? 3) Output Amperage -Need specialised equipment 4) Pulse Shape -See brochure by NZ Agricultural engineers institute - Pulse behaviour -again specialised equipment necessary . As voltage is the only criteria that can be easily measured it is often over emphasised. Good voltage can mean a good fence line, and not necessarily a powerful energiser. Under load the energiser can break down loose it's power. Joule rating is a more accurate indication of an energisers capability. Beware -some manufacturers give their energiser's capability in terms of stored energy, while others give output energy. i.e. A 6 joule stored energy energiser does not' equal 6 joule output energy energiser. Power is lost when an energiser discharges (internal resistance) so output energy by giving what is leaving the energiser is a more reliable source of power rating. An over simplified rule of thumb - One Joule output energy will power 10 km's of fence wire.
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nzaei agricultural engineering institute
ELECTRIC ELECTRIC FENCING FENCING NOTES NOTES
PULSE BEHAVIOUR
The shock you or an animal receive when touching an electric fence is caused by a very short pulse of electricity produced by the energizer where even 100 volts, if continuously applied can cause death, the electric fence pulse may reach 5000 volts or more. The reason no harm is caused is due to the very short length of the pulse -it is over in 0.3 milliseconds. This is sufficient time to cause strong muscular contractions and pain, but little else. This serves the main aim of an electric fence, to make contact with the wire extremely unpleasant. The shape of the pulse, which can be shown by plotting voltage against time, may take many shapes as is shown for typical New Zealand energizers in Figure 1.
6,000 5,000
Voltage (Volts)
4,000 3,000 2,000 1,000 0 -500
100
200
300
400
Time (Microseconds) Figure 1: Typical Electric Fence Pulses The pulse travels on typical electric fences at about half the speed of light or 150,000 km/sec. As it goes, energy is lost from the pulse as it's passage heats the wire and through leakage to the ground through insulators etc. This means that the peak voltage slowly decreases as the pulse travels, an effect known as attenuation.
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The shape of the pulse is also distorted as it travels. On typical electric fences, high frequencies travel faster than low frequencies. The high frequency components of the pulse are represented by the steep edges or nearly vertical part of the electric pulse and the low frequencies by the more horizontal parts. To complicate the issue further low frequencies are attenuated less than high frequencies. An approximately ideal waveform for long fences is a sinusoid as shown in Figure 2. This pulse shape has few high frequency components and will be little distorted as it travels on the fence. Even so, the leading edge of the wave will become steeper and the trailing edge more prolonged, again tending to reduce the peak voltage.
6,000 5,000
Voltage (Volts)
4,000 3,000 2,000 1,000 0 100
200
300
400
Time (Microseconds) Figure 2: Ideal Electric Fence Pulses
On a well insulated fence more than say 5 km long, it is frequently possible to measure a higher voltage at the far end of the fence than at the energizer. This effect is caused by the electric pulse reflecting back on itself at the end of a fence in the same way a wave on water reflects off a concrete wall. The reflected part of the pulse adds to the reflected part as it folds over itself. Reflections don't only occur at at open ends" of a fence. In general they result whenever a pulse encounters a change in fence geometry. An open end is an extreme example where the whole pulse reflects back and adds to itself. At the opposite end of the scale, at a short circuit, the pulse reflects back in reverse polarity, subtracting from itself thus cancelling the incoming pulse. In between these two extremes, say where a "Y" connection is made with three fences, the arriving pulse is partly reflected back and partly transmitted to the two outgoing fences, the exact voltages being dependant on the fence geometry.
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In very long fences, ie. greater than 20 km, the pulses can be identified individually travelling along the fence. However in a more practical situation, with short lengths of fence interconnected in a complicated network, the pulse gets reflected from many different places, giving rise to new pulses travelling in new directions. This makes the prediction of network performance difficult so that the progress of individual pulses can only be practically predicted by a computer. The result is a continuous spectrum of conditions, from the very long fence where an individual pulse can be identified travelling on the fence to a very short piece of wire where the pulse reflects back and forth thousands of times before attenuating and dying away to nothing. In the case of the long fence the pulse may have already finished leaving the energizer before it reaches the far end of the fence. Obviously the energizer can't do much about supplying more current into a short circuit at the far end in this case. All the energy must come from that already stored in the electric fields surrounding the fence. At the other extreme, with a short length of wire the pulse can reflect back and forth many times gathering energy from the energizer every time to supply more energy to the short.
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PLANNING YOUR LAYOUT
" HE WHO FAILS TO PLAN, PLANS TO FAIL"
Plan your layout with the future in mind, consider :-
.Future expansion. Influences choice of energizer . .Species to be controlled. Influences design offence . .The positioning of the energizer. As central as possible. This will reduce the load on the energizer . . .The positioning of the fence lines. Observe basic conservation planning principles. Construct square camps . .The installation of cut-out switches. This will facilitate future fault finding. .Wiring configuration. Parallel vs series, wet or dry wiring configuration . .A maintenance / hygiene program. Systematic cleaning and routine inspections i.e. earthing system, tightness of line clamps, condition of lightning diverters
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LEAD LEAD OUTS OUTS
Wood post firmly fixed to building
Use strain insulators on posts
Galvanised steel fence wires
Insulated Cable
Insulated cable from energiser in building to overhead wires
1) OVERHEAD
2) UNDERGROUND
2m 3m
3m
3) ON OFFSET BRACKETS
Earth Rods
Earth Stakes
Use thicker diameter wire 3 to 4 mm instead of 2,24mm. Run wires in parallel -reduces resistance. Use aluminium or aluminium-coated wire. Always install underground lead-outs in protective tubing.
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STRAINER STRAINER ASSEMBLIES ASSEMBLIES A A FENCE FENCE IS IS ONLY ONLY AS AS GOOD GOOD AS AS IT'S IT'S STRAINER STRAINER POSTS POSTS
Single Strainer Assembly This simple end assembly provides an economical alternative. It is best suited for hard ground and short strains
Diagonal Stay Assembly This construction is more effective and rigid that the single type.
Box Assembly The box assembly is best suited to very soft ground or in areas where there is a lot of ground movement.
GOOD FENCES MAKE GOOD NEIGHBOURS
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INSULATION Insulator -A material which resists the flow of current PROPERTIES OF A GOOD ELECTRIC FENCE INSULATOR 1) It must be made of material which has good insulating properties 2) It must be physically strong 3) It must be U.V. stable 4) It must be well designed for the purpose it is intended i.e. Long flash over distance 25mm Have a hard smooth surface Easy to clean Not retain water Be easy to attach TYPES OF INSULATION Fire proof i.e. Porcelain -For permanent fences Fire resistant i.e. G.F.T. / Securi -For perm. & Security fences High quality plastic -For temporary fences . TYPES OF INSULATORS 1) Strain Insulators 2) In- line Insulators -Nail-on, Bobbin 3) Screw-on / Pig Tail -For strip / Temporary fences
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WIRE Wire used for conventional fencing is chosen primarily for it's physical characteristics of strength and durability (corrosion resistance). While these two properties are important in electric fencing, one must now also consider the electrical properties of the wire. RESISTANCE For wires of similar composition, the thinner the wire the greater resistance. Paralleling or braiding the wires together can reduce resistance. The resistance of wire is also dependent on its chemical composition. I.e. Copper and aluminium are better conductors than zinc or stainless steel.
TENSIONING Do not over tension fence wires. Tension between 800- 1000 Newtons.
HANDLING/STORAGE Handle wire with care avoiding damage to the galvanising. Store wire in a dry place away from fertilizers, lime or other corrosive chemicals.
WIRE SPACING Rule of Thumb-live wire nose / shoulder height to the animal you wish to control
JOINING WIRES Poor joints can be a major cause of power leakage.
When joining wires together in the middle of the fence line use a figure 8 or a reef knot
When joining wires always use hot dipped galvanised line clamps. Stafix Standard Joint Clamp.
Use 2.24mm high strain galvanised steel wire (VELD 1000)
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INTRODUCING INTRODUCING GAME GAME TO TO ELECTRIC ELECTRIC FENCES FENCES "TALKING ELECTRIC FENCING"... BY MAURICE WILLIAMSON All animals need to be trained to respect electric fencing. It is therefore very important that your animals receive a good shock the first time they makes contact with your electric fence. So, assuming that your fence is well constructed, that it is the right design for the animals you intend to control, that it is adequately powered, and that it is well earthed, your animals must then be given plenty of time and space to learn that their new perimeters are hostile. Don't rush them. and don't cramp them. Below are some tried and tested methods of introducing game to electric fences :1) Power up the electric fence as construction proceeds. This should be done on a daily basis. The reasons for doing this are :(i) It will ensure that the more inquisitive animals receive a good shock the first time they make contact with the fence. This will help reduce the time needed to train your game as the leaders will either communicate, or the herd will sense, that their new perimeter is hostile. (ii) It will reduce the incidence of damage to the fence line caused by animals testing it while it is off. Besides causing damage the fence, your game will also lose respect for it and then it will take you longer to train them when the fence line is switched on. (iii) It will enable you to check for faults as construction proceeds. It is very frustrating switching on a newly erected electric fence and then having to walk kilometers of fence line looking for faults. 2) Pad wipe the live wires with molasses. As a rule of thumb live wires should be situated at nose height to the animals you intend to control. A simple way of attracting the game to sniff the live wires is to wipe some diluted molasses onto the live wires. The game will soon learn, via their damp muzzles, what electric
A variety of species, a variety of sizes
Aluminium Spinner (wind activated)
3) Attach tin cans, aluminium strips, or metal spinners to the live wires. Not only do these attachments improve fence visibility if scented, as in 2) above, with molasses or milk powder, they will further attract the game to approach cautiously and investigate.
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
4) Install flashing neon lights on the fence. Commonly called live lights, these lights draw the power needed to make them flash from the energiser's pulses. These flashing live lights improve fence line visibility and this in turn prevents nocturnal feeders, such as hippos, from blundering into the fence. Live lights will also enable you at night to see at a glance if your fence is working. 5) Maintain power on the fence line at all times. Unlike on a stock farm where domesticated animals soon become accustomed to electric fences, on a game reserve one encounters a variety of species, and also changing populations of the same species, which will vary in size, age, and sex. These variations will result in different behavioral responses to the electric fence. Further, the wilder an animal, the more sensitive it appears to be to an electric fence and the sooner it will detect if an electric fence is switched off. So rather than let your animals detect that the electric fence is switched off and have them break out, make sure that your electric fence is switched on at all times. The installation of live lights, or a simple electric fence voltage monitor, will also enable you to continuously monitor your fence line and to be sure that the power is on. It is advisable to keep a spare energiser module as a standby. 6) Consider the Season. Time of year and season will also influence your animal's response to an electric fence. In the dry winter months one is not only faced with the problem of poor soil conductive. and inefficient ground earthing but the animals themselves are also better insulated with their thicker winter coats. It is better to introduce animals to electric fencing during the wetter late spring or summer months. 7) Keep the fence line clean arid well cleared. This will not only reduce voltage and power losses but it will also help prevent animals from blundering into the fence line. A strip three meters wide on either side of the fence line should be kept clear of bush and trees and the grass kept short. A weedicide may be sprayed directly under the fence line but beware of causing erosion in hilly areas. Game will come to associate this well cleared strip with a shock. 8) Electrify trans-location Bomas. Just as commercial cattle fanners use a well fenced, electrified, training camp to introduce new animals to electric fencing, so too should the game fanner. By attaching electric wires onto the interior of your boma you can train your animals in the boma to respect electric fences. These offset electrified wires should only be switched on once the animals have settled down in the Boma.
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BASIC ELECTRIC FENCING
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INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
TRAINING TRAINING ANIMALS ANIMALS TO TO ELECTRIC ELECTRIC -- FENCING FENCING All animals need to be trained to respect electric fencing. It is therefore important that animals that are being introduced to electric fencing are given time and space to learn that their new perimeters are hostile.
The following tips will help facilitate the training process
1) Have a well fenced electrified training camp
2) Pad wipe the live wires with a watered down solution of molasses.
3) Attach cans or aluminium strips to the fence wires to improve visibility .
4) Power up the fence line as construction proceeds. This is particularly important when erecting a game fence. . i) To ensure that the game receives a shock the first time it makes contact with the fence.
ii) To reduce the incidence of fence damage caused by untrained game testing the fence while the power is off. iii) To enable the erector to check for faults as erection proceeds.
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
FENCE FENCE DESIGNS DESIGNS The effectiveness of electric fencing depends on a number of factors: The normal flight reaction of the species. The investigatory or neophobic responses of the species. The animals ability to sense the fence or it's wires by vision, smell, or touch. The capacity of the animal to learn . The tool using ability of the species. Once the. responses of animals are understood, electric fencing has tremendous flexibility .By adjusting the number and height of the wires, by selecting the appropriate spacing, by adjusting the current..etc, one can achieve a specific design that will meet the behavioral pattern of the species. Whereas entire populations of farm animals can be trained to respect electric fences, the control of wildlife is more complicated, Here one has to deal with a mixture of species, changing populations, a spread of ages, and changing sizes of the animals to be controlled. As a rule of thumb set live wires at nose / shoulder height to the species you wish to control. Fence creepers such as zebra & sable can be effectively controlled with a wire at 250 to 300mm.
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
POWER POWER FENCE FENCE DESIGN DESIGN FOR FOR DRY DRY AREAS AREAS WHERE WHERE EARTHING EARTHING IS IS A A PROBLEM PROBLEM
2400mm
GROUND
2100/2200mm
Long Offset
1350/1400mm
Short Offset
750/800mm
Short Offset
250mm/300mm
Short Offset
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
POWER POWER FENCE FENCE DESIGN DESIGN FOR FOR DRY DRY AREAS AREAS WHERE WHERE EARTHING EARTHING IS IS A A PROBLEM PROBLEM
2400mm
GROUND
2100/2200mm
B & B Long
1350/1400mm
Short Offset
750/800mm
Short Offset
250mm/300mm
B & B Short
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ELECTRIC FENCE AND SECURITY CENTRES
JACKAL JACKAL AND AND LYNX LYNX FENCING FENCING DESIGNS DESIGNS
1100mm
350mm 250mm 130mm
GROUND Using 2 x Short (225mm) Offset and 1 x Rod (10mm) and Insulation
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INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
WILD WILD PIG PIG FENCE FENCE
Using 2 x Short (225mm) Offset and Bonnox / Veldspan Wire
Bonnox / Veldspan
600mm
600mm
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
FAULT FINDING For efficient and effective fault finding a Digital Volt Meter and cutout switches are essential. BASIC FAULT FINDING PROCEDURE 1 Disconnect the energizer from the fence and using a D .V .M. test that the energizer is operating correctly. 2 If O.K. reconnect to fence. (If not O.K. change module). 3 Check earth system (not rusted, connections tight, sufficient stakes). 4 Check that the lightning diverter is not blown 5 Proceed to first cut out switch: a Switch OFF. Using the D.V.M. check the voltage on the live section of fence. b If voltage is low the fault is between this switch and the energizer. c If voltage is normal switch the cutout ON again and proceed to the next switch. Repeat the procedure. d Continue with the procedure until the fault is found. 6 Always check the voltage on both sides of gates and lead-out. 7 While walking the fence keep an eye open for: a Broken or tangled wires. b Excessive competition from vegetation. c Trees or branches across the wire. d Loose or corroded connections. e Dirty or cracked insulators. f Listen for "popping" as you walk along the fence. 8 The closer you get to the fault / short the lower the voltage reading. Beyond the fault the voltage may increase again -if not a dead short.
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BASIC ELECTRIC FENCING
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INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
GATES Gates for electrical fences pose special challenges such as ease of use, visibility, durability, continuity of current flow.etc. Gates in an electric fence system can be either" conventional or electric. If conventional gates are used it is recommended that they be reinforced with live wires to prevent them being used as rubbing posts by the livestock ADVANTAGES OF ELECTRIC GATES Low cost. Easy to fit. Requires less support. Width easily adjusted. Can be adapted to make electrified grids. Can be adapted for river crossings.
TRANSFER OF CURRENT Current can be transferred from one side of agate to the other by going either overhead or underground. It is generally recommended to go underground using double insulated underground cable protected in polythene pipe.
GROUND EARTH RETURN LIVE LIVE LIVE LIVE 300mm (1ft)
FENCE EARTH RETURN LIVE EARTH LIVE EARTH 300mm (1ft)
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ELECTRIC FENCE AND SECURITY CENTRES
FLOOD GATES FLOOD GATE CONTROLLER (G604) Switches bottom wire off during high water.
JOINT CLAMP (G603 OR G603N)
HOT DIPPED CHAIN
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"TALKING "TALKING ELECTRIC ELECTRIC FENCING" FENCING" ELECTRIFIED ELECTRIFIED MOTOR MOTOR GRID GRID
BY TUBBY HARDMAN (Q.B.E.)
In this article I endeavour to detail how we at TNH Fencing have addressed the challenge of preventing game from passing through gateways that are used frequently by motor vehicles. We have solved the problem by means of the electrified motor grid. The electrified motor grid is based on the conventional cattle grid quite simply, the electrified motor If you were impressed the first time you saw a springbok Pronk - you ain't seen nutting yet - wait and see how an elephant can Pronk after it touched an electrified motor grid.
grid is a cattle grid with a bite in it. Electrified motor grids can also be added to conventional cattle grids thereby increasing the effectiveness of the cattle grids. One simply runs live wires directly over the gaps in the cattle grid. (Doing this will avoid any wear and tear on the wires)
While electrified motor grids are ideal for the entrance to a reserve, or to the hotel/lodge and camping sites, I would not recommend this type of grid on a busy public road. Modern, low clearance, luxury vehicles travelling at high speed tend to rip up the live wires. A live wire "sproinging" up and wrapping around the prop shaft of a guest visiting your reserve will not exactly impress the guest. The Electrified Motor Grid
ELECTRIFIED GAME FENCE
Grid Specifications Width of the Grid 3.5 Metres Length of the Grid 2,0 Metres Number of Wires 12 (All ilve) Spacing of the Wires 150mm apart Height above Ground 100mm Retaining side Wires 500mm above ground
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BASIC ELECTRIC FENCING INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
Construction of the Electrified Motor Grid 4) GFT Strainer
6) Cut-out Switch
7) Screw in insulators
1) 4 x 12,2m (100 / 125)mm Treated Poles 2) 2 x 2m (100 / 125)mm Treated Poles 3) 4 x GFT strain insulators 4) 2 x Atlas strainers 5) 12 x Line Clamps 6) 1 x Heavy duty Cut-out Switch 7) 24 x Screw-in Ring insulators 8) 24 x 6mm Ferrules 9) 24 x 30kg Restricted Tension Springs 10) 50m of 1,5mm braided wire (Stainless Tell or Galvanised) 11) 1 x Tape Gate 12) 2 x Live Lite 13) 2 x Warning Signs 14) 5m of Under Gate HT Cable 15) 1,2m of threaded Rod, plus 8 nuts and 16 washers 16) ,25m of Sande, Stone, Cement
4) Atlas Strainer Wire Tensioner
9)
Restricted Tension Spring
11) Tape Gate
Set the four 1.2M retaining poles in concrete. Use cut lengths of threaded rod bolt on the two 2M cross poles at ground level. Now attach the four OFT Strain' insulators and the two Atlas strainers to the four retaining poles and strain a live wire on each side 500mm above ground level. These live wires will prevent animals entering the grid from the sides and will also act as the live feeder wire to the grid. Fit a heavy duty cut-out switch onto the straining post of the game fence. Using double insulated .undergate cable, connect one side of the switch to the electric fence and the other to the grid's retaining wire. This will feed power into your grid. By having the cut-out switch, one is able to switch off the grid when working on it, or when walking across it. Install the live-lite on the wire transferring the power from the fence to the grid. This light will serve two purposes; firstly it will warn you that the power is on, and secondly, it will help deter animals from crossing the grid. . Now screw the Screw-in Ring insulators onto the 2m cross poles, spacing them 150mm apart, and " hook on the springs, one per insulator. Measure off the braided wire making sure to leave a tail on one end to connect up to the retaining wire. Thread two ferrules onto each braided wire. Connect one side to a spring crimping it in position with a ferrule, then stretch the wire between the springs and crimp. : Do not over tension as the springs will be left with no elasticity .Over tensioning can also result in the springs snapping. ' Finish off by joining the tails of the wires to the retaining feed-out wire by means of the line clamps. The grid wires should be all live and should be set 100mm above the ground. Any higher and they may hook a vehicle, any lower, and you may have shorting. Switch on and watch the animals Pronk. In conclusion it is also advisable to install a tape gate on the electrified motor grid. This tape gate will enable you to close the gateway securely at night, should the need arise. Finally, make sure that everyone on your reserve knows how the grid works and what to do if there is a problem. Tubby Hardman is CEO of TNH FENCING cc, a company that specialises in electrified game fencing. Tubby has been involved in the electric fence industry since 1985, first as a sales person, then as a sales manager for a major electric fencing distributor, and finally as the owner of his own fencing company. TNH Fencing currently holds the tender to maintain all the electric fences on the northern province's Madikwe Game Reserve. Madikwe Game Reserve can justifiably lay claim to having the best maintained game fences in Southern Africa. Indebted to Tubby for so freely sharing his experience with us.
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BASIC ELECTRIC FENCING
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INTRODUCTORY TRAINING COURSE
ELECTRIC FENCE AND SECURITY CENTRES
RADIO AND TELEPHONE INTERFERENCE All Stafix "cyclic wave" energizers comply with the international radio frequency interference(R.F.I.) regulations. However problems can occur, particularly in areas with poor radio reception .
Clicking on the radio or telephone can be caused by :~ The energizer being too close to the mains power earth. ~ A bare earth wire touching the building. ~ A poor mains power earth. ~ Loose connections in the energizer or plugs.. ~ The electric fence running parallel to telephone or power lines. ~ Poor or rusty joints on the fence line. ~ Damaged cut-out switch or cracked insulators. ~ A broken cable under a gateway. ~ Vegetation arcing / touching the fence ~ Any mechanical short. To detect if the fence is causing the problem disconnect the fence and the earth wires from the energiser and switch the energiser on. If the clicking stops the problem is on the fence line or earth. If the clicking continues then the problem is either in the energiser or the mains power supply. Check the plugs. If the problem is in the mains power supply the clicking will stop immediately the when the energiser plug is pulled. If the problem is in the energiser an extra click will be heard after the energizer plug is pulled.
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