Datamars 0.5 J MkII Unigizer Mode D'emploi page 72

Building a permanent
electric fence
Components of an electric fence
An electric fence system comprises the following
elements:
An energizer.
•
An earth system.
•
of metal rods inserted into the ground,
which are connected to the Fence earth
terminal on the energizer.
Insulated underground cables.
•
fence wire coated in insulated plastic,
suitable for use underground or going
through walls. Used to connect the
energizer to the earth and fence.
An insulated fence.
•
Fence output terminal of the energizer.
Fences can be made to a variety of designs
(see below).
Other useful components that can be added:
Cut-out switches
regular intervals, these allow you
to isolate sections of the fence for
repair.
Lightning diverter kit
minimise the damage to your
energizer from lightning
conducted down the fence line.
Typical installation
For an electric fence to give an electric shock,
the current produced by the energizer must
complete a full circuit. The current leaves the
energizer and moves along the fence wires
through the animal, into the soil and back to
the energizer via the earth system. If the earth
system is ineffective, the animal will receive an
inadequate shock. The fence below has all live
wires and requires conductive soils. This type of
earthing system is often referred to as an
'all-live' or 'earth-return' earthing system.
72
This comprises a number
Electric
Connected to the
. Installed at
. Used to
Alternative installation
Dry, sandy or non-conductive soil (e.g. volcanic
soil) provides ineffective earthing. For this type
of soil it is a good idea to use additional earth
rods, choose a better location for the earth
system (such as damp soil), or use a
'fence-return' or 'earth-wire-return' earthing
system.
For a 'fence-return'/'earth-wire-return' earthing
system, the Fence earth terminal is connected
directly to at least one non-electrified fence wire
(earth wire). The animal gets maximum shock
from touching a live wire and an earth wire at
the same time.
Fence designs
Fences can be constructed to suit the type of
livestock and materials available. Discuss with
your reseller which design best suits your needs.
Some suggested fence configurations are
below.