Electric fences have a high degree of psychological deterrent in that people fear them. The technology used in an electric fence delivers painful yet harmless electric shocks.
The fence is usually formed of multiple, horizontal wires mounted on an existing (or new) physical barrier. The electrified wires are mounted on the inside of the fence using isolators that space them about 100mm from the fence itself so that accidental shocks are avoided.
The electrified wires are monitored for faults and can also act as detection zones that will trigger if someone touches or attacks the fence. Electric fences have a high rejection to nuisance alarms because they have to have an object physically touch to create the alarm and that object has to have a rout to earth so, for example, a bird landing on it will not set it off. A wet carrier bag blown in the wind could register as an event but is unlikely to alarm because even though the water conducts electricity it won’t be conductive enough. An animal such as a fox could trigger it but the fence control system can filter out and ignore the first two pulses so that the fox gives up and runs away. Three pulses or more or damage to the fence causes an alarm. With this said, electric fences need to be installed at least 1m away from large vegetation and grass around the bottom needs to be maintained