Electric Fences - Key Tips on Installation

Electric fences are not impenetrable and South Africans should be aware of the methods criminals use to bypass this widely-used security measure. Below an extract from MyBroadband who engaged wih Fidelity CEO Wahl Bartmann and Bull Security operations manager French Jooste to learn how criminals circumvent electric fences and what could be done to stop them.

Some of the other most common methods used to access an electric fence are:

• Getting through electric fences was a so-called “V stick”. “Criminals will insert this stick underneath the electric wires to lift the wires away from the wall, creating a small space to climb through,” Jooste said.

• Bend the fence downward away from the wall

• Broken the solid brick wall or palisades underneath the electric fencing to gain access to properties.

• Opening a gap in the fence using conduit pipes to lift the wires without touching each other. 

• Slipping conduit pipes with a slit cut along their length over the wires so that they are isolated from each other.

• Climbing over at wall corners or by using steps on the wall. 

• Cutting the fence at more than one place at the same time. 

• Isolating part of the fence using high tension cables, then cutting the wires between them. 

The main reason why these tactics work is because the electric fence may not be pulled taught enough, not properly installed or maintained, or had a weak design. An electric fence should be checked regularly for damage to the insulation, the earth loops and connections, to ensure it is working correctly.

To avoid your fence being bypassed using one of the tactics above, there a few key points to consider during installation:

Resistance — Use low-resistance wiring like aluminium. Aim for under 500 ohms per energiser.

Height — If a wall allows for a foothold, the fence should be higher than 800mm.

Zone numbers — Reducing the fence length per energiser zone allows security companies to find the point of penetration faster.

Lifespans — Low-end fencing lasts five years, premium fencing lasts ten years.

Wall characteristics — A wall should only have a few steps, be more than 2 metres high, and consist of a double row of bricks.

Choice of installer — Get a consultant to write a technical specification for the fence and send this to several electric fence installers that operate in your area. Ensure the installer is properly registered to issue a Certificate of Compliance.

Spikes can be installed on top of the wall to make it harder to slip under the fence. 

Fence must be connected to an alarm so that it can send a signal to your security company if it is cut, damaged, or opened up. A beam and camera system linked to your phone and security company can also be helpful.

Smart analytics camera is helpful and learns what is normal behaviour and also can alert security companies, residents or business owners to any activity that crosses a specific line.