Electric Fencing 10th May 2021
How an Electric Fence Works
Understanding how an electric fence works, will help you to design your fencing solution.
Let’s try to simplify the workings of a common Electric Fence .
An electric fence energiser delivers a high voltage pulse, typically 8000 volts every 1 – 2 seconds.
The high voltage is required because most animals have a high resistance to electricity due to thick skins and fur or wool, as well as cloven hooves.
Although the voltage is high, the pulse is very short, typically 20 – 300 microseconds depending on the size of the energiser.
This short pulse in itself will deliver a shock, but does not last long enough to stop bodily functions. The diagram below shows a typical electric fence and how an animal receives a shock.
An animal needs to simultaneously touch both an electric fence live wire and an earth of some sort, to receive a shock. The high voltage pulse must return to the energiser through the earth system before a shock is delivered.
The ground is not always a good earth, as it needs moisture to be able to, conduct electricity. Therefore it is highly recommended that 1 or more earth return wires be installed.
