Nothing is more annoying than having your electric fencing not doing its job because there is insufficient energy to function. Searching for problems in an electric fence is essentially a step-by-step process.
In order to be able to do this an adequate tester is essential or you are just guessing, The only alternative is to use your hand and I assure you – it hurts! A tester that shows if a fence is running at 6000v is far better than those on the market with a single LED light that only shows if there is a minimum of 2000v. This is an absolute minimum and the fence may only be 2100v which is not adequate for every application.
Is the Energiser Working?
Remove the energiser from the fence and earth stake – test directly between the red live terminal and the black ground terminal. If the voltage is over 6000v the energiser is fine and the fence is faulty. If there is reduced or no power, get the energiser seen to.
Faulty Earth stakes account for 80% of problems.
Place a steel rod on the fence simulating an animal touching the fence then test between the earth and the ground terminal on the energiser – if there is current showing your earth rods are faulty. Mild steel rods develop rust which is a poor conductor – use only galvanised steel, stainless steel or copper rods.
Check the underground High Voltage Cable.
This is often chewed by rats or moles, broken by heavy traffic or simply dug up. Disconnect from the fence and test at the end. Replace if necessary.
Fault finding on the fence.
If you are able isolate shorter lengths of the fence this does help. If the fence can be separated into several sections (by switches or by disconnecting parts of it), you can locate the problem by beginning close to the energiser and progressively turn on sections of the fence as you work away from it. When the voltage suddenly drops you can assume that the problem is in the section most recently connected.
1. Walk along the fence looking for any point where the energised wires touch ANYTHING not plastic, the soil, vegetation – grass or leaves, wood, water, snow, a steel post or steel wire.
2. Look carefully for damaged insulators. A crack in the plastic will allow energy to track to earth.
3. Check all connections to ensure a correct transfer of energy.
4. Take readings along the fence, if the fine wires in the rope/tape are damaged you should be able to pick up where they are broken and repair them there.
A phenomenon known as induction is common with electric fences. This is the transfer of electricity from an electrified wire to a non electrified wire or gate without the wires physically touching each other. This is caused by magnetic fields being set up and collapsed by the pulsing nature of an electric fence current. These magnetic fields will generate a current in an adjacent wire even if it is not touching it and draw energy off the fence itself. This is often mistakenly blamed on insulator leakage. Common where the earth line and the fence line run next to each other out of a building.
Simply separate the wires by about 30cm. This is also more common in areas where the air is damp such as in conditions of fog. As this phenomenon is a quirk of nature it cannot be stopped from occurring.
However, to avoid receiving shocks caused by induction on non electrified fences and gates etc. you can “ground out” the offending fence by connecting a ground wire to all wires on the non electrified fence. Push the end of this wire into the ground as far as possible and this will send all the offending voltage into the ground.
A small AM/SW radio is an invaluable tool. Set off-station it receives the radio signals emitted by a short circuit in the fence line where a fault results in arcing of the electrical energy. The pulse of a fence fault is registered as a loud “click” – these get progressively louder the closer you get to the fault. This is generally used on extensive fences where a motorbike may be used to check fences. On small areas it can be confusing as the clicks may register from a distance.
Agrisellex Electric Fencing has been trading for 40 years and is backed by companies that have been manufacturing for 75 years.