Electric fences

  By Raymond

An early version of the electric fence was developed by New Zealand inventor William Gallagher. It took a year to develop it and was finished on 1937, built from a car's ignition coil and a Meccano set, Gallagher used the device to keep his horse from scratching itself against his car. Gallagher later started a company to improve and market his invention. Today the Gallagher Group of companies is still heavily involved in electric fencing for livestock control.

Electric fences were used to control stock in the United States in the early 1930's, and developed further in both the United States and New Zealand.

Design and function

Electric fences are designed to create an electrical network when touched by a person or animal. A component called a power energizer converts power into a brief high-voltage pulse. Every second a terminal sends electric pulses along the fence through a power energizer . Another terminal is connected to a metal rod implanted in the earth, called a ground rod. An animal touching the wire and the earth simultaneously will complete an electrical circuit and will conduct the pulse, causing a painful electric shock. The effects of the electrical shock depend upon the voltage and electrical current used, and can range from painful to lethal.

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