Lightning is the biggest threat for telecommunication towers and radio&tv towers. Telecommunication towers are made of steel to remain stable for years and are constructed as the highest structures around in order to supply communication with no interruptions.
Lightning usually hits the sharpest and tallest object in an area because ground charges emitted from objects with high elevations reach to opposite charged streamers of the cloud earlier than the charges from any shorter object. On the other hand, lightning current aims to reach ground by following the shortest and most conductive way. That is why, a tall metal structure such as a telecommunication tower is the primary target for lightning strikes.
When lightning strikes on one of the top sharp corners of the tower, lightning current flows down to the ground through tower legs and damages all electronic equipment like radomes, radios, antennas, dishes, etc.. on tower body. On the way to the ground, lightning current also can leak into the shelter located nearby the tower and give irreversable damage to sensitive electronic devices inside.
“Protection” by Lightning Arresters
Lightning arresters try to attract lightning on themselves in order to avoid a lightning strike at any other point. They are installed on the top of the structure and connected to a conductor cable which is bonded to a grounding system at the bottom of the structure. The purpose here is to attract lightning before any other object around and let lightning current flow down to the ground through the conductor cable. This method may be preferrable for protecting structures made of concrete or similar low conductive material considering that conductor cable of lightning arrester is a better way for lightning current to reach ground comparing to concrete body.
However, when a lightning arresting solution is applied to a tall tower made of conductive material such as steel, lightning may still hit the arrester but lightning current prefers to flow through tower body instead of conductive cable since that it would be a faster and easier path to the ground.
There are two reasons for this; 1) Conductor cable is usually made of copper or aluminum and gets corroded in short time and becomes less conductive comparing to tower body which is made of long-lasting steel, 2) Like other high voltage sources, lightning prefers to follow large surfecas instead of a tiny copper cable.
As a result, there is no difference between installing a lightning arrester solution on a telecommunication tower and leaving the tower unprotected because even if lightning strikes at the corner of the tower or lightning arrester, lightning current still follows the same path to the ground which is tower body. During the flow, all equipment on tower body and also inside the nearby shelter are under risk of getting damaged irreversably.
Lightning must be kept away from the site.
EvoDis® Lightning Prevention System
Best way of being protected from direct lightning strike damages and secondary damages by electromagnetic field of lightning current is to keep lightning away from the tower.
The point of lightning hit depends on the ground charge accumulation and emission on a structure and reach of these emitted charges to oppositely charged downward streamers. Lightning hits the point of emission and lightning current flows down to the ground through the structure.
EvoDis® Lightning Prevention System dissipates the charges on structure through thousands of tiny sharp points and blocks the emission of these charges. This process makes the protected site “invisible” to lightning and prevents a possible strike on it.
EvoDis® Lightning Prevention System is a lightning protection solution with 100% success in high voltage laboratory tests and in field tests. EvoDis® has been applied to hundreds of towers worldwide and none of these towers have been hit by lightning since the dates of installation.
Best way of lightning protection is to stay away from lightning.
EvoDis® Lightning Prevention System keeps lightning away.