1. What are the basic needs in an electric fence installation?
  2. What do I need to set up an electric fence?
  3. How does an electric fence work?
  4. Terms and abbreviatlor at a glance.
  5. What is Voltage (V)?
  6. What is currebt (indicated in Amperes A)?
  7. What do we understand by resistance (indicatet in Ohms)
  8. What do we understand by energy
       (indicated in Joules J=W9/  1 Joules = 1Watt in 1 second)
  9. Limit values for electric fences.
10. How do I find the right fencer for my needs?

1. What are the basic needs in an electric fence Installation?
Fencing in = prevent animals from breaking out (danger of accidents!)
Fencing out = protecting people, crops or plants and other objects (including theft protecting).

2. What do I need to set up an electric fence?
Electric fencer (mains, solar or battery powered)
Wire (or other electically conductive material such as polytapes, polywires or polyropes)
Posts (or the support parts) made of wood, plastics or metal to support the conductors.
Insulators (to insulate and hold the conductors in the correct heights)

3. How does an electric fence work?
A correctly designed and constructed electric fence works by creating a psychological imprint in the mind of animal.
A fencer (or energizer) attached to the fence, produces a short, sharp and painful shock when the fence wire is touched so the animal learns to respect the fence and stay clear of it.
These shocks are pulses of energy, harmless to animals and humans and far safer than barbed or razor wire and, after a brief training period, create a more effective barrier at lower cost than traditional fences.
Electric fencing is extremly durable and, if properly planned and erected, is totally secure providing an impenetrable barrier to contain or exclude both wild and domesticated animals.
An electric  fence is a complete system comprising three primary components which must be ``In balance”.
The fencer represents the heart of the system. It produces the energy to cause the shock. The duration and intensity of this shock depends on the capacity of the fencer (measured in joules).
Typically the pulse or shock duration would be between 0.001 and 0.003 seconds and at approximatoly and second intervals.

4. Terms and abbreviatlons

Electric fencing terminology sign and formula Voltage measured in Volts (V) U Current measured in Amperes (A) I Resistance measured in Ohms (W) R Conductivity measured in Siemens (S) G = 1/R Reserve of resistance also Mho (1/W) 1/R Performance measured in Watts (W) = (VA) P = UxI Energy measured in Joules (J = WS = Vas) W = UxIxt Time measured in seconds (s) t

5. What is Voltage(V)?
230V mains supply typically used for household appliances and potentially dangerous if touched.
12V car batteries no shock can be felt
9V blockbattery no schock can be felt
1,5 latern battery no shock can be felt
Voltage needs to be at least 40-60V to overcome the resitant of an obstacle such as skin or clothing.
You can also compare voltage with the pressure in a waterpipe.

6. What is current (Indicatet in Amperes A)
As the name indicates already something is flowing. In this case electrones (comparable to flowing water in a waterpipe). This current/flow can be measured. The amount of current depends on the voltage level and the conductivity (S) / resistance (W) of the fence installation (line and ground).
Physical dependance:
II current = U/R (Voltage / resistance) or
 I current = U*G (Conductivity)

7. What do we understand by resistance (inicated In Ohms / Watts)
Resistance is the measure for the obstruction of the free current flow. This resistance depends on the material of wire / diameter or on the ground (sand, gravel, humus, tar, wood, rubber and very importent: wet / dry)
In a waterpipe system a good conductor (little resistance) can be compared to a clean, smooth tube with a big diameter and a bad conductor (a lot of resistance) with an internally corroded, filthy tube of little diameter.

8. What do we understand by energy (indicated in Joules J = Ws / Joules = Watt second)??
Energy represents a certain performance (work) within a specific time. This energy can be stored (f.i. in a condenser) and can be released when needed.
The energy available is frequently called stored energy. This stored energy is made available to the fence with eacn impulse on the fence. The energy will be consumed partly or fully depending whether a contact takes places (closing of the circuit: fencer > fence > wire > body > ground > fencer) The amount of consumption depends on the resistance in the fence circuit and the value of the impulse energy.
Therefore, the impulse energy depends on
a) resistances in the fence installation
b) the stored energy and
c) the operating mode of the fencer
To stick to our comparision with water: the stored energy can be compared to the amount of water available in the cistern above the toilet, the amount used corresponds to the effective impulse energy.

9. Limit values for electric fences
As per 01.01.1998
For a living body a resistance has been estimated at 500 ohms
Max. fence voltage 10000 V
Max. fence voltage on body contact (500W) 10A
Max. impulse energy on body contact (500W) 5J
Impulse intervals - minimum 1s (one second)
Fencers with less than 0,1 are considered to be totally harmless.

10.  How do I find the right fencer for my needs?
When selecting your fencer also first looks for the energy supply. If you have a pasture close to the farm mains unit will be the right choice. If the pasture is far to the power you can benefit from the advantages of 9V fencers. They are lightweight and handy thus flexible in use. If you need more power you can choose a 12V fencer for connection to a 12V wet battery possibly with (additional) solar option.
Your ideal fencer also depends on the type of fence you need. What is important in this respect is to determine the right power / performance of your fencer. Look for a unit with sufficient energy supply (impulse energy) and high voltage (Volts) on fence load.
There is the following basic rule:
Fencers with little impulse energy below 0,2 Joules are suitable for easy to control animals and short fences with little load.
Fencers with high impulse energy up to 5 Joules are suitable for animals that are difficult to contain and normal weedload. Fencer with high impulse energy of more than 5 Joules are suitable for long fences and heavy vegetation growth.
It is not longer the energy that counts but also the voltage (measured in Volts) must be sufficient otherwise there will be no current flow. Look for the fence voltage, as it is not the voltage without load that is important but the voltage on animal contact. A minimum voltage on animal contact of 2000V is necessary, 3000 to 4000V are recommended especially for long haired animals, animals with a thick hide or stubborn ones.