There are three types of electric fence powered by electric grid, solar and battery. Each type of electric fence relies on a charger to convert the charge into a safe form of electricity.
As explained, an electric fence converts battery or solar power into high voltage pulses. Early alternating current (AC) fence chargers use a transformer and a mechanically-driven switch to generate the electrical pulses. The pulses were wide and the voltage unpredictable, with no-load peaks in excess of 10,000 volts and a rapid drop in voltage as the fence leakage increased.
The electric fence energizer transfers the pulse to a fence insulator that will give the deer the 'shock.' This usually transfers a response in less than 3 seconds. When the wild animal, be it deer or rodent, makes contact with the fence, the animal will quickly pull away from the fence.