Today, it is common knowledge that lightning protection is more than just a cage consisting of air termination, down conductor
and an earth termination system.
An internal down conductor
is usually installed inside the blade for conducting the lightning current from the attachment point to the hub, as shown in Figure 1.
This is a possibility if the down conductor
passes through the center of the boat and the LPS is not designed to accommodate internal lightning currents.
The lightning protection for the administration building consisted of two Franklin rods, separately grounded via two down conductors
. The tower had one Franklin rod installed with the tower serving as down conductor
and its footings as grounded electrodes.
The down conductor
interconnects the air and earth terminals and provides a preferential low-impedance lightning path to earth away from crew, components, systems, and materials that might be injured or damaged.
A lightning protection system includes a "rooftop network" of lightning rods or air terminals at the top of the house connected by a series of down conductors
to carry the current down to a grounding network (grounding rods or ground plates, depending upon soil conditions).
2, there are an equipotential bonding bar and six down conductors
on the building.