All mains operated energizers must comply with various local standards. These standards vary but the following regulations are common in most countries.

Always use insulated cable when connecting a ground system to the energizer to ensure that no wires come into contact with sheds etc. This is particularly important with milking sheds as cows are very sensitive to even very low voltages in this environment.
An electric fence ground system should not be connected to any plumbing system, including disused water pipes or old bore casings, nor should it be connected to any other grounding device.
An electric fence earth system should be at least 133ft away from any other electrical earth system or telephone earth system.
Each energizer should be connected to its own ground system and this should not be connected to any other ground system.
Do not connect two or more energizers to the same electric fence.
Never connect any fence energizer to barbed wire of any description.
Do not attach an energizer or electrified wires to any post of any overhead power line unless authorized to do so.
Try to avoid erecting a fence which runs parallel to or runs under power lines. Where this is unavoidable the crossing should be underneath the power lines and as near as possible at right angles to the lines.
Where a fence is in the vicinity of over head powerlines, no fence wire should be higher than 6'6" above the ground.

Try to avoid running a fence line parallel to telephone or telegraph lines or near any radio tower.
When an electric fence is installed where it might reasonably be expected to be touched by the public, then warning signs must be attached.
The warning sign must be at least 8" x 4" in size and should be affixed to the fence at intervals not exceeding 295ft

The sign should also display the words ELECTRIC FENCE or show the symbol depicted.

Any lettering should be indelible, at least 1" high and it is recommended that the color of the sign be yellow with black inscription.

In areas prone to bushfires, power the fenceline from the 1/2 voltage terminal or turn the energizer off on days of extreme fire danger.
Where the energizer is used to supply a system of conductors used for deterring birds from roosting on buildings, no conductor should be connected to ground. A switch should be installed to provide a means of isolating the energizer from all poles of the supply and clear warning notices should be fitted at every point where persons may have ready access to the conductors. The notice should bear the words "LIVE WIRES" in block letters not less than 1/2" high. The letters should be red on a white background and the size of the notice should not be less than 2 1/2' x 2" overall.
Do not connect on energizer simultaneously to a fence and to any other device such as a Cattle Trainer or Poultry Trainer, otherwise, lightning striking your fence will be conducted to all other devices.
If in doubt check the regulations with your local authority.