- The top of the ESE must be 5m
above the zone it protects. ( including
antennas, cooling towers etc).
- Any receiving antennas (TV, radio,
telephone) must be connected to the
down conductors via a spark gap.
- The coaxial cables of these antennas
must be protected with an appropriate
surge protection device.
- Any metallic items that rise above the
roof level must be bonded to the
closest down conductor.
DOWN CONDUCTOR SYSTEM
- Each ESE must be connected to at
least one down conductor. At least two
down conductors are required for the
- If the width and breadth of the
structure is larger than the height.
- Where the height of the structure is
greater than 28 m.
- The two down conductors must be
located on the opposite sides of the
- Down conductors must be as straight
as possible and the shortest path to
the earthing system. Bends not to
exceed 20 cm.
- Down conductor must be on the
outside of the building and not near
electrical or gas pipes.
- An earthing system is required for
each down conductor.
- The earth resistance must be less
than 10 ohms.
- It is recommended to have an
inspection box with a disconnection
point such that the earth can be
- Cross bond the ESE earth(s) to the