CHARGE DISSIPATION TERMINALS CHARGE DISSIPATION TERMINAL

TerraStat is the latest design in lightning dissipation technology. Science and experience show that TerraStat Charge Dissipation Terminals, and the structures on which they are installed, are much less likely to sustain a direct lightning strike than unprotected structures or structures with traditional lightning protection systems.

TerraStat®Charge Dissipation Terminals Securely contribute to ALLTEC's Protection Pyramid methodology for comprehensive facility protection.

ALLTEC's clients appreciate that these terminals may be installed under the auspices of UL 96A Master Label lightning protection systems; thus, in the exceptional event of a lightning strike terminating on a CDT, the system meets or exceeds the protection provided by a traditional air terminal.

Whatever your requirements, we have a product to fit the application. For those special applications, we have the capability to design and manufacture a custom system to fit your needs.

To understand how Terrastat® works let us first understand the process involved in a thunderstorm and development of a lightening strike

As a thunderstorm builds, a break down point is reached and the cloud begins sending down charges called ‘stepped leaders through ionized paths in the atmosphere. Multiple stepped leaders begin propagating towards the ground in three dimensions looking for the highest accumulation of ground charges in the area. The charges move in steps of approximately 50 mtrs, stop & look for the best potential, then move again. These steps & redirections gives lightening its appearance.

Once the stepped leaders reach within about 10 to 150 mtrs of the earth, objects on the surface where the opposite ground charges have accumulated begin to form upward streamers. The energy from the stepped leaders actually pull the charge off objects on the earth's surface in the form of upward streamers. At this point, the object on the ground that provides highest concentration of charges and the best formed streamer become the most likely target for the nearest stepped leader and complete the path of lightening strike. Once this occurs, charges from other stepped leaders originating from the same source recede and dump the energy through the established neutralization path. TerraStat is the latest design in lightning technology. They are Provides enhanced performance over traditional lightning protection with patented technolgy.

CHARGE DISSIPATION PRINCIPLE

Charge dissipation technology uses the point discharge principle to facilitate dissipation or reduction of a build-up of static electric charges. The sole purpose of static dissipation products is to reduce the accumulation of electrical charges and thereby prevent an electrical arc or an electrical current flow that can cause damage.

When a pointed grounded conductor is placed in a high electric field (such as on a structure located in a thunderstorm) voltage effects at the point are increased greatly. Electron from the atmospheric atoms and molecules are stripped away and flow to ground through the grounded conductor leaving behind positive atmospheric ions around the point. This process is referred to as the "CORONA EFFECT”.

This corona effect begins long before charge accumulation reaches a critical level when step leaders begin forming in the storm cloud. The result is an accumulation of ions around the point. Since like charges repel from each other, the accumulation of ions disperse/dissipate in all directions away from the point. Electrons left behind from this dissipation of ions flow to ground and neutralize the positive charges accumulated on the ground and on the structure. This is an ongoing process as the thunderstorm builds and passes over the facility.

A single point such as a lightening rod or as occurs on the corner of a tower/structure, will reach a point of saturation to the extent that it cannot disperse charges at a fast enough rate to keep up with the charge accumulation. These areas then become the points where streamers will form thereby attracting a lightning strike to themselves.

When the process is magnified with the addition of thousands of points in a charge dissipation terminal, the dissipation of ions is magnified many times over that of a single sharp point. The resulting effect is that the ground charge which develops streamers attracting a lightning strike no longer have sufficient electrical energy supporting them to initiate this process. Without the formation of an upward streamer, the downward stepped leaders will look for a better target.

Alltec offers a full array of Terrastat® models to protect all types of structures or facilities.