Earthing a fence energiser is essential in order for it to deliver an effective shock. Good earthing consists of earth rods and clamps. The length and number of the earth rods required depends on the fence energiser you are using:- portable energisers: minimum length 0.5 metre. - 12V energisers: minimum length 1 metre . - Mains energisers: Adviced minimum length 2 metres. Gallagher earth rods come with earth clamps and are galvanised for long life and excellent conductivity.