Lightning Protection System Design and Products
The first step in designing a lightning protection system is Risk Assessment. Axis has used the guidelines of IEC 62305 Part 2 to design a Risk Assessment Software that allows you to assess the risks and determine the Class of Lightning Protection System (LPS) for your structure. This software uses parameters unique to your structure to help you determine the best and most efficient protection system.
Based on this, you can now design the external and internal protection systems for your building. The External protection systemwould include an Air Termination, Down Conductor and an Earth Termination System. For internal protection, one would use surge protection devices and equipotential bonding.
The positions of the Air Termination can be decided based on the rolling sphere method, the protective angle method and the mesh method. The rolling sphere method can even be used to define the zones of protection for structures with complex geometry. The radius for the sphere is determined directly from the Class of LPS.
The Protection Angle method is used for simple structures but only up to a certain height as determined by the class of LPS.
The Mesh Method is best used for flat surfaces where the air termination conductors are to be placed at the roof edges and where no other metallic structure will be above the air termination system.
Axis Air Termination Rods, made from high grade electrolytic Copper, provide the highest conductivity that allows the flow of lightning strikes without any damage to the structure or equipment.
Non-Conventional Air Termination Systems
According to IEC-62305, the zone of protection determined for an air termination system shall be defined only by the physical size of the system. There is noconclusive evidencethat this zone can be enhanced, as claimed by manufacturers of Early Streamer Emissiontechnologies. Thus, no IEC Standard recognizes the ESE technology.
Down conductors, connected to the Air termination system with suitable Axis products, should take the most direct route down the structure, with spacing between each one defined by the Class of LPS.Axis Copper Clad Steel Down Conductors are specially developed to offer the high mechanical strength of steel and the current carrying capacity of Copper.Since IEC 62305 also allows the use of rebars inside concrete structures as down conductors under certain conditions, Axis offers specially designed products to use this technology effectively.
An Earth Electrode should provide low electrical resistance with the earth to allow for the dissipation of currents. It should also be resistant to corrosion because it will be buried underground for a long period of time.
Worldwide, one of the most popular Earth Electrodes are copper bonded earth rods, which comply with IEC 62561 Part 2. Since electricity is a surface phenomenon, the copper layer allows for a conductive path while the inner core of high strength steel provides the strength required for driving the rod inside the ground. Axis Copper Bonded Earth Rods have been are approved by Utilities across the world and continue to be popular due to their consistently high quality.
The two major components of internal LPS are Equipotential bonding and surge protection devices (SPD’s). The purpose of Equipotential Bonding equipment is to bring all the metallic parts and equipment in a structure to the same Voltage Potential, to avoid hazards to human life or other damage. SPD’s protect electronic devices by breaking the circuit in case of an equipment or system fault.
Since 1994, Axis has continued to manufacture and supply high quality lightning protection and earthing equipment internationally. We have a proven track record of high quality protection. Our customers include Utilities, Government Organizations and Private Projects across the globe.