Electric fencing is a very popular, versatile and effective form of fencing and can be used in both temporary and permanent fencing situations. This information guide will give you the customer a better understanding of electric fencing and an insight in to how the products are used.
An electric fence works in the following way:
The energiser puts out a high voltage, low current pulse, approximately once per second, through a special conductive fence line. This may be stranded wire, electric fencing poly wire, electro tape or electro rope. The fence line must be totally insulated from the ground so that there is no leakage of current to the earth. This is why good quality insulators are an extremely important part of the system. This enables the maximum voltage difference between the earth and the fence line to be achieved.
When the animal touches the live fence line, it will complete the electric circuit and will feel a shock as the current flows through its body, into the ground and back to the energiser via the earth stake. The animal will remember the shock so the electric fence then becomes a psychological barrier and the animal learns to stay away.
The energiser - An energiser is the unit that creates the high voltage pulse shock on an electric fence. There are many different types of energisers. Each is differentiated by the following.
Power Source - Battery (dry disposable or 12 volt wet rechargeable), depending on model. Mains and solar systems are available.
Voltage - The amount of shock on the fence line under different loads created by such things as vegetation and very long lengths of fence.
Joules - This determines the distance of fence line that can be satisfactorily electrified. The higher the joules, the longer the fence can be and the higher the shock produced.
Earth Stake - The best possible earth is essential and is often the part of the fencing sale that is overlooked. A good earth is required to allow the current to flow from the energiser, along the fence line, through the animal into the ground and back to the energiser via the earth stake, thus completing a circuit. If an insufficient earth is used, then too low a fence line voltage may be achieved to give a large enough shock to the animal. In dry or sandy ground conditions, the current flows less easily than in damp conditions so you may need more than one earth stake.
Basic Fence Types
||Portable / Temporary (Battery)
||Semi – Permanent/Permanent (Mains and Battery)
|Expected fence use
||Short term, frequent moves.
|Ease of installation
||Easy to moderate.
||Cattle, horses, pets, lawn and garden
|Cattle, horses, pigs, sheep, goats, exotics, deer and predators.
|Best suited for
||Temporary fencing, managed intensive
|Pastures, cross fences.
||Step-in posts, steel and rod posts.
||Round wire posts, plastic posts and wooden posts.
||Poly wire, poly tape, poly rope
||Poly wire, poly tape, poly rope and steel wire.
||Lightweight, reusable, easy to move.
||Workable with any configuration of posts and conductive wire.
||Minimum recommended voltage on fence line
||Recommendations and Characteristics
||Use high visibility products such as poly tape or poly rope.
||If docile with plenty of pasture 1-3 strands adequate.
||Extra shock needed to control a determined bull, 4 strands recommended.
|Sheep and Goats
||3,000 - 5,000 volts
||Difficult to confine (Goats jump, thick coats require higher voltage), 4-6 strands.
|Nuisance pests and vermin
||Smaller animals require closer wire spacing.
||To deter from rooting, use 3-4 wires starting 15cm from ground level.
|Foxes and Predators
||Multi-wires spaced 13-20cm apart from ground level.
||Multi-wire fence 1.8 - 2.5m high using high visibility tape or rope.
||1,000 - 2,000 volts
||3-4 wires, starting 15cm from ground.
How to Determine the Field Perimeter Length
|Field size in acres
||Fencing length required in metres
Approximate Energizer Distances
||Distance in metres
||Up to 150 mtrs = 12 mm tape (no vegetation on line)
||Up to 250 mtrs = 12/20 mm tape (no vegetation on line)
||Up to 400 mtrs = 20 mm tape
Up to 800 mtrs = 40 mm tape
Up to 500 mtrs = Rope/super white poly wire
||Up to 3,000 mtrs = 40mm tape
Up to 1,250 mtrs = 20mm tape
Up to 500 mtrs = 12mm tape
Up to 2,000 mtrs = Maxi poly wire
Up to 1500 mtrs = Super white poly wire
||Up to 250 mtrs = 20 mm tape
Up to 250 mtrs = Super white poly wire
||Up to 1,000 mtrs = 20/40 mm tape, rope and super white poly
||Up to 3,000 mtrs = 40 mm tape/maxi rope
Up to 2,000 mtrs = 20 mm tape/maxi wire/rope
Up to 1,500 mtrs = Super white poly wire
||Up to 4,000 mtrs = 40 mm tape
Up to 3,000 mtrs = Maxi wire/Maxi rope
Up to 2,000 mtrs = 20 mm tape/Maxi wire/Electro rope
There are several variables that will affect the distance that an energizer will perform to. The following need to be taken into consideration:
- Age and state of battery
- Overgrown foliage and the EARTH.
To achieve distances the tape/wire/rope need to be in good order, with good connections, and with no vegetation touching the fence line. You will also need a good enough earth for the system and for the unit to be as close to the fence line centre as possible.
Battery charging is also essential. To recharge a 12 volt 85 amp battery use a 12 volt 12 amp charger for a minimum of 24hrs (not just overnight) A 12 volt 6 amp charger will take 48hrs.