The European union is shortly passing legislation that energisers may not exceed 5 Joule output rating. This has been done on safety grounds and that the larger units simply are not required within the EU. A 5 Joule energiser can power up to about 130klm of wire and very few - if any- situations in Europe require that sort of energy.
The safety comes from the mathematical equation that determines the Joule rating. This is a simple formula of Voltage x Amperage x Pulse length. Therefore a 5 joule energiser would have a sort of configuration like;-
- Voltage = 6000v
- Pulse Length = 1/300th of a second
- Amperage = 250 milli amps
In order to build an energiser that will release 25 Joules onto a fence some pretty clever technology has to be devised in order to be able to SAFELY achieve this. As any of the parameters are increased so the safety of the fence is decreased;-
- Increase the voltage and the spark becomes larger, better able to jump a larger distance and burn a recipient. The highest an energiser may run and is regarded as safe is about 16000volts.
- Increase the pulse length then the body is subjected to the shock for a longer period and the possibility of the "grabbing effect" of electricity coming into play.
- Increase the amperage and you are encroaching into the areas where a heart will be affected. It is generally accepted that 500 milliamps is the highest this may be taken.
Unfortunately the big New Zealand manufacturers see this as a trade barrier and have referred it to the World Trade Organisation.
“The French delegation was effectively trying to impose a non-tariff trade barrier by proposing a new standard drastically reducing permitted power levels. They said this was for safety reasons but our view – which was backed by the majority of countries present - is that it was a commercial issue.
“They were trying to bar New Zealand 's very successful electric fencing products from being marketed worldwide other than with a very low power output.”
It is true that these large energisers have been on the market for years and have not resulted in deaths, they are used in wide open spaces with little population pressure - very different to the European situation. In addition to that the New Zealand companies already compete in the European market with smaller energy energisers so their business model is not affected.