Joining Wires and Line Clamps for Electric Fences

It is important that every metal part of your electric fence is galvanised. It is best to have only one type of metal throughout your fence. If two different metals are in contact there is corrosion caused by electrolysis. Any combination of steel, brass, copper or aluminium will corrode. Corrosion leads to a high resistance at the joint and loss of pulse strength.

Cold galvanising compounds such as Galmet or Killrust are useful for long-term protection against corrosion at wire joints.

Knots

Three types of knot, are satisfactory to join wires.

Many of the commonly used knots will do for wires in an electric fence. However, keep the following points in mind:

This is a strainer knot suitable for a wire around an end straininsulator

• use a strainer knot for wires around posts
• the knot should not weaken the wire too much
• the knot should not flex after the wire is strained
• avoid short circuits by cutting the loose ends back to the knot
• the knot should have a number of contact points with the hot wire
• knots in earth return wires are as important as they are in hot wires.

NOTE: The Double Loop knot, useful on other parts of the farm, causes a lot of resistance if used in electric fences.

When you join plastic twines, it is preferable to separate the wire strands so that they may be twisted and joined together. Both ends should also be knotted to take the fence strain.

Line clamps and removable connectors

You need some type of line clamp and removable connector to provide electrical continuity in the fence. Do not simply twist one wire onto the other because the connection becomes loose with time.

Post Spacing

On flat ground, posts can be 20 in apart, or even further. On ground that is particularly flat, you can have them 50 m apart with two or three light droppers in between.

However, it is important to remember you must have the fence wires parallel to the ground. This means you need a post at every rise and a post or anchored dropper at every hollow. When the ground is uneven you need many more posts. In some hollows, you need to tie-down the posts.