Such systems have three main
parts
● air terminal, sharp copper spike;
● system down conductors made robust copper strip;
● earth termination, providing solid and reliable connection with
the general mass earth that the energy can harmlessly dis-
persed into the ground.Statutory regulations and codes practice
273
An intrinsically safe system, suitable for use Zone one which
all the equipment, apparatus and interconnecting wires and circuits are
intrinsically safe.
.
The building receives zone protection from lightning strike the
shape cone, starting the highest point the air terminal the light-
ning protective system shown Fig. included the circuit ‘back-up’ case the first Zener diode
fails. 13.
Lightning protection systems (BS 62305: 2008)
Many buildings historical interest tall buildings such churches are
fitted with lightning protection system protect the building and those
who use from the harmful effects lightning strike upon the building.
The average lightning discharge current the order 20,000A and is
this discharge energy through structure that causes the damage.7
The zone protection for structure given cone with its apex the highest point the air
termination.
FIGURE 13.7.
Zener diode too low for conduct, but fault occurs, the voltage
across and will rise, switching them and blowing the protective
fuse.
Lighting protective systems offer the lightning strike alternative low
resistance path the general mass earth
