Electric Fencing Energisers FAQs

1 April 2017  |  Admin

Electric Fencing Energisers FAQs

wooden posts with 40mm tape fittedWooden posts with 40mm green electric fencing tape fitted

Electric fencing energisers come in several formats, with different power supplies and features.  Is is usually the single most expensive part of your electric fence and customers often have many questions.  here we try to answer some of the most frequently asked questions:

What is an energiser?

An energiser is a box that converts power to controlled electrical pulses that run along your electric fence.

How much does an energiser cost?

The price of energiser varies depending on the power of the energiser, the place of manufacture and the features.  Typically energisers range from £80 to £500 pounds.  The average energiser hovers at about £120.  More powerful energisers cost more money.  Mains energisers are typically the best value.

How long does an energiser last?

An energiser should last a good number of years.  Most come with a 1 or 2 year warranty, with some brands even offering a 7 year warranty.

How should I select an energiser?

The first decision you need to make is how you are going to power your electric fence.  Do you have access to the mains?  If so, a mains energiser is usually the best option.  If your electric fence is not close to a mains outlet and you do not wish to run any cable, you need to consider battery powered energisers.  You can select a 12v energiser for which you would also need a 12v rechargeable leisure battery, which cost £69.99.  An average sized 12v energiser (designed for a paddock or medium sized field) will run for approx 2 weeks on a 12v rechargeable battery before the battery needs to be taken in to be recharged.  If you can’t face the idea of lugging your battery in to be charged, consider adding a 10w Solar Panel (£32.99) on top of your battery, which will charge it up for most of the year in the UK.  Another option is the 9V energiser, which requires – you guessed it – a 9v battery!  These 9v energisers have the advantage of being easy to move around should you be heading off to events or moving your temporary electric fencing.  You can select the power of your 9v battery, but they will need to be replaced every few months (they are not rechargeable).  Finally you can consider an all-in-one solar energiser, which are becoming increasingly option due to the ease of set up and low maintenance.   The all-in-one solar energisers are slightly more expensive to start with, but obviously there is no need to buy batteries or solar panels!  The solar energisers will eventually need to have their rechargeable battery replaced as the energiser will outlive the battery(much like a mobile phone usually outlives its rechargeable battery) but this is an easy job.

Why are there different electric fence lengths given for the same energiser?

Electric fence manufacturers used to test their energisers under ‘perfect’ conditions where there was no long grass and brand new top of the range electric fencing wire.  This gives an unrealistic idea of how the energiser performs in the real world.  It is important to always look for the distance guide that represents your terrain.  For example, if you have light vegetation make sure you look at the energisers guide distance for light vegetation (it will be about half of the ‘test condition’ distance).  It is a good idea to select an energiser that can handle a slightly larger distance that your fence because this will ensure you have enough power to push through any kinks in your rope or tape.

When selecting the length of my field, do I need to multiply it by how many strands of electric fence tape or rope I have?

No!  Most manufacturers now give a ‘multi-wire’ distance when saying the length of fence their energisers can power.  However, be wary of cheaper unknown brands and double check what they mean when they give a distance.

What type of earth stake do I need?

This depends on the energiser and each energiser should come with an earth stake recommendation.  You can never have an earth stake that is too large, so if in doubt go for the larger option.  If you have dry land, a lot of clay or a very powerful energiser, you may even use 2 or more earth stakes.  the earth stake is the most important part of the electric fence – do not scrimp here!

What other features should I look for in an electric fence energiser?

There are a whole range of features on offer.  I find the LED displays that tell you when you battery is getting low to be useful.  Many people like the ability to dial up and down the power on their fence, although if you have an electric fence to keep animals safe it is a good idea to keep it on all the time – it is amazing how many animals know the second you turn the fence off!  Day and Night time modes can be useful; for example, you can set your poultry electric net to have high power during the night when the foxes come out.  Another simple feature is the ability to turn the energiser on and off, rather than having to disconnect it from the power source.

Are electric fences safe?

Yes!  They are safe for animals and people, although if you have a pacemaker it is best not to touch it.  The zap from a fence does not feel nice, but it will not harm you.  The whole idea of an electric fence is to keep your animals safe – not to hurt them!

Do I need an electric fence warning sign?

You only need a sign if your fence is on a public footpath, at which point you need to place a sign every 50m.


If you have any questions about electric fencing, please don’t hesitate to call.  We help people select the right fence for their needs every day.

Here is one of our popular ‘dual purpose’ energisers that can be used on a 12v battery or on the mains:

Trapper AN8: suitable for horses, small fields, poultry nets.  £89.99



Here is a popular 9v battery:

Equistop B1: Perfect for horses and paddocks.  Easy to move.  £89.99 inclding 3 month battery.



Here is a popular all-in-one solar energiser:

AS20: Ideal for small fields. Very easy to install and maintain.  £179.00



FarmCare UK

Electric Fencing, Solar and Clipper Expert

01323 406212


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