Basic Definitions for Electric Fence Laws
The electric fence laws use the following definitions for the wording in the text:
This is a fence that is made up of one or more electrical conductors which are insulated from the earth. An energizer is used to apply electrical pulses to these conductors.
This is an electrical conductor. It is used to attach the energizer to the earth electrode or electric fencing.
Electric Security Fence
This is a fence that is specifically used for security. It is comprised of both an electric fence and a physical barrier. The physical barrier is not connected to the electric fence.
Public Access Area
This is an area where people are separated and protected from the electric fencing by means of a physical barrier.
These are electric conductors that receive high voltage pulses from the energizer.
This is where there are no physical barriers to protect a person from electric fence conductors that are below a height of 1,50 m.
Electric Fence Laws for Installations
- Installed and operating electric fences must not cause any harm to animals, people or their environs.
- If an electric fence can entrap people or animals, it must not be installed.
- An electric fence must not receive electrical pulses from more than one individual energizer. It must also not be supplied by separate fence circuits of the same energizer.
- If there are two separate electric fences, each with its own energizer that has independent timing, the space between the wires of the fences must be at least 2m. If this gap is smaller, a barrier made of isolated metal or a non-conductive material must be inserted between the two fences.
- According to the electric fence laws, razor wire or barbed wire must not be used for electric fencing.
- If an electric fence is installed next to a public pathway or road it must have clear warning signs secured to the posts or wires at regular intervals. These warning plates must be at least 100 mm x 200 mm in size, yellow in colour and with black text. This text must be present on both sides of the warning sign and must be at least 25mm high. (For further details, please refer to SANS 10222-3:2016 Ed5)
- Warning plates must be placed at every access point and gate along the electric fence as well at intervals of 10m or less. If there are any signs close by, that caution of chemical hazards, electric fence warning plates must be placed next to these too.
- Gates along electric fences must be safe for people to open without being shocked.
- The earth electrode of the energizer must be at least 1m underground. The minimum distance between an electric fence earth electrode and any other earth system is 2m.
- Any connecting leads that are installed in buildings must be insulated from the building’s earthed structural elements. An insulated high-voltage cable can be used for these purposes.
- Connecting leads that are installed underground must be protected from external factors. This can be achieved by either using insulated high-voltage cable, or an insulated conduit.
- Connecting, as well as signalling, leads may not be run in a conduit together with other wiring or cables e.g. the mains wiring, communication cables etc.
- Electric fence wires and connecting leads may not run above overhead communication or power services.
- Electric fence laws dictate that wiring for the mains supply must not be installed together with electric fence signalling leads.
- Crossing overhead power lines should be avoided. If this is not possible, the crossing must run under the services line as perpendicular to it as possible.
- Electric fences that are installed near overhead power lines must have a minimum clearance. Refer to table 1 in SANS 10222-3:2016 Ed5 for these details.
- Electric fences that are installed near overhead power lines must not be more than 3m high.
- When an electric fence crosses bare power conductors, the highest metallic part must be earthed for at least 5m on both sides of the crossing.
- This height applies both sides of the rectangular projection onto the ground of the outer power line conductors, for a distance of: 2 m where power lines have a nominal voltage less than 1000 V and 15 m for power lines with a nominal voltage greater than 1000V.
- Electric security fence parts and equipment must be installed, operated and kept so that people do not get shocked unless they attempt to get through the barrier or are not supposed to be in the secure area. Any conductive parts of the fence that are exposed, must be properly earthed.
- If connecting leads or conductors are not run from the same energizer, there must be a distance of 2.5m between them. If these leads or conductors are insulated and rated to a minimum of 10kV, the spacing can be reduced. This spacing does not apply where conductors are supplied by separate energizers and there is a physical barrier (that doesn’t have any gaps of more than 50mm), between them
- If separate energizers supply pulsed conductors, electric fence laws state that there must be a vertical distance of 2.5m between them.
- There must be isolation between electric fence ancillary equipment and the supply mains that is equal to that of the energizer. Ancillary equipment must be protected from the elements unless the manufacturer has certified that it is fitting for outdoor use and that it has a degree of protection that is greater than IPX4.
All electric fence repairs
, new fence installations and maintenance must be done according to the Electric Fence Law specifications.