All About Grounding/Earthing
Earthing will provide half of the circuit of the entire electric fence system when done correctly. This circuit is "completed" when the animal is touching earth ground and then touches the fence.
Almost 90% of the time that a new electric fence is not working, the culprit will be incorrect or improper earthing .
Grounding 1 or 2 wires
Completing the Circuit
For proper earthing, the electric fence energiser will need to have the live terminal connected securely to the wire and the earth terminal connected securely and completely to the earthing rod(s).
If the earthing system is poor or insufficient, electricity cannot complete a path to the energiser, and as a result, little or no shock is given. An animal completes this path when it touches the fence wire and the earth ground simultaneously.
For most electric fence systems with dirt or moist soil, one 2m earth stake will be sufficient. However, rocky, sandy and dry soil may require multiple earth stakes placed 2m apart to completely create a circuit. Also, longer electric fences often need better earthing systems, so in these cases, multiple earth stakes may be needed as well.
For the smallest electric fence systems such as those used around a garden or flower bed, a 60cm earth rod is often sufficient to allow an animal to complete the circuit.
The Grounding Rod
We recommend a galvanised earthing stake. Using the proper earth stake will improve the chances of getting a good ground on your electric fence system.
Driving a 2m earth stake into the ground will be almost impossible without a "post pounder" which should be available at the same place that you purchase your electric fence supplies.
Be sure to connect the earth stake to the ground terminal on the energiser and not to the fence terminal or the fence wire.
Grounding 1 or 2 wires
One Wire System
The one wire system means that there are only live wires running the perimeter of the fence. One wire systems are often used for smaller areas - areas with only one or two strands of wire. Often a live strand of wire is run along the top of an existing traditional fence to keep the livestock from reaching over the fence.
Two Wire Systems
A two wire system is a great way to help the animal complete the circuit by touching the live and a ground wire at the same time. The two strand system is used when there are multiple (3 or more) strands of wire and the wires alternate between live and grounded wire. The idea is that the wire is alternated between live and ground wire on the fence: one live the next ground, the next live, etc.
This is most often used for large areas and has the benefit of increasing the chances of the animal touching a charge and a ground and thus completing the circuit. Additionally, the two wire system is ideal for areas with sandy or rocky soil. This system is also well-suited for animals with long hair or wool.
For these electric fence systems, the earth wires will be connected directly to the earth stakes or the and the live wires will connect directly to the fence terminal.
There are 4 steps to ensuring a proper ground for your electric fence system:
- Install the energiser as instructed by the manufacturer, usually in a building or weatherproof area. Solar fence controllers should be mounted outside, facing the sun for maximum sun exposure.
- Drive one to three 2m ground rods (galvanised) into the earth. If multiple rods are needed, they should be about 2m apart for best results. Multiple rods are often needed if the soil is dry, rocky, sandy or subject to freezing during part of the year.
- Connect an insulated wire to the earth terminal on the electric fence energiser and the other end of the wire to the earth stake using a line clamp.
- Connect the "fence" terminal on the energiser to the insulated fence wire. Turn the energiser on.
Q: How do I drive the earth stake into the earth?
A: Using a hammer to drive a 2m grounding/earthing rod into the earth would take a long time and could be very painful. The same store that supplied your electric fence products should also have a post pounder that will make installing an earth stake much easier.
Q: Is there a way to check if my electric fence is properly earthed without shocking myself?
A: An earth wire or earth stake which gives a shock when touched indicates a poorly earthed system. Make certain that the joint is clean and firmly attached to the earth stake. There are electric fence testers that serve this purpose. Ideally there should be no more than 400V on the earth stake if you put your tester on it.
Q: The soil here tends to be fairly sandy. How many earth stakes should I use for my 10m by 10m garden? I’m trying to keep the rabbits and squirrels out of my vegetables!
A: Small areas like that even in sandy soil will probably be fine with one earth stake. Note: Rabbits can be hard to keep out (or in) because they can run fast enough so that by the time the feel the shock they may already be through. Rabbits can also jump over low fences. Multiple low wires and a few higher wires will work with enough power..