Considering Lightning Rod Protection? Talk to Us.

Since the dawn of civilization, lightning has inflicted a great deal of damage on the structures built by mankind. About 250 years ago, an effective method of protection became available when Benjamin Franklin invented the lightning rod. A great deal of the research done since then was regarding how to best utilize lightning rod protection to dissipate lightning at a reasonable cost.

A lightning protection system functions by intercepting the direct lightning strike energy as it hits near a structure and safely diverting it to the Earth. Lightning phenomena is roughly based on the discharge of huge charge regions high in the atmosphere into the Earth. This discharge initiates high overhead and starts a rapid descent “in the general direction” of Earth with no real high resolution target. In other words, the lightning does not have a real plan when it starts to fall, but only near the end do the step leaders feel enough electric field influence to reach up and connect. This all occurs in 10’s to 100’s of microseconds.

When you need a lightning rod protection, there are many options available. Understanding how they work will help determine what will meet your needs. And while none of them are wrong, some are better suited for different applications.

Franklin Rod

The science of lightning rod protection was born when Franklin discovered that lightning was a form of electricity. The conventional protection method consists of the following:

a) Deploying air terminals at suitable points above the structure to act as sacrificial termination points for the lightning strokes.

b) Dissipating the collected lightning charges safely into the ground via ground rods that are connected to the air terminals via down conductors.

c) Bonding the down conductors to any nearby conducting objects in the building to prevent side flashes.

 

Dissipation Array System

Charge dissipation, or charge transfer technology uses point discharge to reduce static charge build-up. The purpose is to prevent an electrical arc or current flow. Lightning rods, with their single point, will reach a charge saturation level where the point cannot disperse the charge faster than it is accumulated. These points are where streamers form and attract downward leaders resulting in a lightning strike. DAS terminals, on the other hand, are engineered with thousands of points to maximize corona generation and ionize surrounding air thus neutralizing accumulated charges. There’s not enough energy to initiate the formation of an upward streamer, and the downward stepped leaders will look for another target.

If you are considering lightning rod protection, your best bet is to talk to a lightning protection specialist such as LEC as every site and budget will have different considerations.