Symbols and terms:


Earthing your electric fence is a vital part of your electric fence. It completes the electric circuit running through your fence.  

A good earth connection is very important as is where and how deep you earth your fence.

To achieve a good earth, a galvanised rod needs to be driven deep into the ground to reach the deep subsoil moisture. This should be positioned at least 10m away from any domestic earth rod. Once you have installed your earth rod it is a simple
matter of connecting this to your energiser.

Fence resistance:

Resistance can relate to several aspects of your

electric fencing;

Earthing resistance; needs to be as low as possible 

Conductive material resistance; this is displayed in ohm/meters. The smaller this value is the better conductivity. The best materials (tape/rope/wire/net) have resistance smaller than 0.25ohm/meter. The longer the fence the more conductive your material needs to be. 

Isolater resistance; this should be as high as possible. You don’t want to loose any power from your tape/rope/wire/net through your connectors and into you posts. 

What kilometre figures should you base your decision on.

Kilometre figures are often theoretical. They are based on the optimum conditions (wire conductivity, perfect connections, perfect insulation, ground conditions, and earthing. ) in the fence system. These conditions change constantly, however, due to the influences of weather. It is therefore important  to achieve the minimum protective voltage of 3,000volts at each point of the fence system in all conditions. 

230 volt power supplies

This is the best choice if a mains socket is available.
Available in all necessary power classes, with unlimited protection period. Providing the best means of delivering the energy required (0.5 joule up to 20joule output) on long fences or fences with vegetation or for robust /stubborn animals. Although this will provide a higher joule output it remains compliant with applicable safety standards.  

Dual powered 12v battery / 230v mains

Best of both these units possess both the 230volt mains and 12volt battery. These units come with main/battery adapters and cables.

12volt battery powered unit

If mains power is not an option then a 12volt battery energisers are the best solution for robust animals or a long fence or a fence with some vegetation. The discharge energy is comparable with mains devices (0.5 joules up to around 20 joules of output) 12volt rechargeable wet batteries are used as the power source. Not all units come with batteries. Batteries will need to be charged on a regular basis. Adding a solar module to this set up can trickle charge the battery over time. However you may still need to charge the battery during long dark winter months. We do advise that invest in two batteries so one can be in charge whilst one is being used on the fence.

9volt dry battery units

These units are suitable for shorter fences with no vegetation. These batteries are much lighter than a 12volt battery. Depending on operating time and pasture size a 9volt battery can run for a few months and may be able to cover the entire pasture. The battery type and size (expressed in Ah) Ampere hours. The higher this value the longer the dry battery will run for. Once this battery has discharged it can not be recharged. 9volt units even if they are 12volt compatible will typically deliver 0.15 joules - 0.35 joules. Only high impact 9volt units can deliver 0.55joules. 

Compact solar units

As we only stock kerbl and Rutland energisers we can only provide information on these compact solar units.  Using a mono-crystalline solar modular in combination with a high performance solar fence device, these energisers are now able to supply power to fences that are many kilometres in length. This can still provide a sufficient power even after a week without sufficient sunshine. These special devices are suitable for large remote areas where mains power is not an option and carrying and maintaining batteries and equipment on a regular basis is heavy and difficult. These units are compact and light weight even though they have a 12volt AGM battery built into the unit which in turn is charged by the integrated solar panel system. If for any reason the unit needs charging it can be charged using mains.

Maximum voltage 

This voltage is reached with a low fence charge.

Voltage in open circuit

 Voltage when no fence system is connected to the energiser.

Voltage at 500 Ohms

Voltage at a fence charge of 500 Ohm

Stored energy.

Energy absorbed by device. The electric fencer efficiency ratio yields the relevant discharge energy value for the user.  

Maximum output 

Maximum energy transmitted from the energiser to the fence system. This pulse is also identified as shock strength.

Output energy 

Minimum energy transmitted from the energiser to the fence system. This can be reached through a fence output with reduced power or by selecting the lowest power level of an energiser. 

Theoretical fence length

With fence lengths in accordance with VDE, only a theoretical value is given, which, as a result of various influences ( fence vegetation, weather and soil conditions) cannot be reached in practice.

Approximate number of electrifiable nets

Vegetation on the fence has a considerable influence on the max fence length for an electric fence energiser. The more vegetation on the fence, the higher the fence charge will be, thus reducing the maximum fence length. The fence length indication refer to highly conductive wire material and connectors, good isolators and an optimal earthing system.

Voltage supply 2x1.5V

3 volt devices are mobile and easy to handle, and are suitable for for very small fences with no vegetation, such as in gardens, game pen control.

Power consumption 

The duration of the battery life can be calculated from the energy consumption along with the capacity of the battery.