If there doubt the route and continuity of
the reinforcing bars within existing structures
then external down conductor system should
be installed. That these
are welded, clamped with suitable connection
components overlapped minimum 20
times the rebar diameter.
—
01 Typical methods of
bonding steel
reinforcement within
concrete. The joints
should then encased moisture
inhibiting compound. These should ideally bonded
into the reinforcing network the structures at
the top and bottom the structure.—
Table Typical values the distance between
down conductors according the Class LPS
(IEC/BS 62305-3 Table 4).
Stranded copper cable
(70 mm²
PVC insulated)
Cast in
non-ferrous
bonding
point
Bonding conductor
Clamped cable rebar
connection
Steel reinforcement within
concrete (rebar)
Stranded copper cable
(70 mm²
PVC insulated)
Cast in
non-ferrous
bonding
point
Bonding conductor
Clamped cable rebar
connection
Steel reinforcement within
concrete (rebar)
113
TECHNICAL REFERENCE IEC/BS 62305-3 PHYSICAL DAMAGE STRUCTURES LIFE HAZARD
.
For new build structures this can decided
at the early construction stage using
dedicated reinforcing bars alternatively run
a dedicated copper conductor from the top the
structure the foundation prior the pouring
of the concrete.
—
01
If the reinforcing bars (or structural steel frames)
are used down conductors then electrical
continuity should ascertained from the air
termination system the earthing system.
When internal reinforcing bars are required to
be connected external down conductors
or earthing network either the arrangements
shown above suitable. the connection
from the bonding conductor the rebar to
be encased concrete then the standard
recommends that two clamps are used, one
connected one length rebar and the
other different length rebar. This dedicated copper conductor
should bonded the adjoining/adjacent
reinforcing bars periodically.
Class LPS Typical distances
I m
II m
III m
IV m
Natural components
IEC/BS 62305 encourages the use of
fortuitous metal parts within the structure
to incorporated into the LPS. This ensure that
those reinforcing bars likely carry lightning
currents have secure connections from one length
to the next
