Lightning rods and accesories
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LIGHTNING RODS AND ACCESSORIES

AND ACCESSORIES > Need for protection > High risk situations described by the regulation > Risk calculation for lightning strike > Design and installation guide using early streamer emission lightning rods > Design and installation guide using rods and meshed conductors > Quick material selection guide > Interception systems and accessories > Rods and meshed conductors > Clips for tape and cable LIGHTNING RODS AND ACCESSORIES

Train derailment due to lightning strike. Wenzhou (China). Lightning is one of the most destructive natural phenomena. There are many atmospheric discharges during lightning storms and some of them can even reach hundreds of kiloamperes. > DESTRUCTIVE EFFECTS OF LIGHTNING These electrical discharges are a great hazard to people, animals, buildings and electronic equipment. The economic consequences of lightning are also very important; it can cause fire, stop production of a factory or interrupt critical processes. A direct lightning discharge to a person results in current flowing through...

Refinery fire due to lightning discharge. Puerto Cabello (Venezuela). Fire in a church tower due to lightning impact. Wald (Germany). Lightning causes the death of livestock. Miracema de Tocantins (Brazil). Lightning strikes a residential building. London (United Kingdom).

The capacity of an installation to provide sufficient protection against lightning protection is guaranteed by compliance with all the regulations in force. > SPECIFIC STANDARDS FOR LIGHTNING PROTECTION NF C 17-102. UNE 21186 and other National Standards “Lightning Protection with Early Streamer Emission Air Terminals”. IEC/EN 62305 Series “Lightning Protection using rods and meshed conductors”. EN 5016 Series (IEC 62561) “Lightning Protection Components”. > GUIDE DOCUMENTS BIP 2118: Protection against lightning. A UK guide to practical application of BS EN 62305. > OTHER STANDARDS...

HIGH RISK SITUATIONS DESCRIBED BY THE REGULATION Area with high density of lightning strikes People in open areas Any installation or machinery used for work purposes Buildings that need a lightning protection system with a certain level of protection, set by a risk assessment carried out according to regulations Structures with outside areas open to the public Need for continuity of public or industrial services Buildings containing highly sensitive or valuable documents or equipment (such as telecommunications, computers, files, museums, historical monuments, cultural heritage) Buildings...

In normal atmospheric conditions, there is a balance between positive and negative charges, where the ground is more negatively charged than the air and other elements on the ground. However, the formation of storm clouds creates a charge polarization: usually, the lower part of the cloud is negatively charged, thereby inducing a positive charge in the ground and other elements on it. The electric field formed in the atmosphere can then reach tens of kilovolts. This positive charge is more evident in metal objects, pointed objects and well-earthed objects, including trees. When the electric...

> RISK ASSESSMENT Protection level is thus related to the accepted probability of lightning striking a structure. A lower protection level (IV) will be able to intercept lightning with a high associated current, but may not capture a flash with a low current. Protection level I assumes more restrictive and safe conditions for the air terminals, hence the system would also intercept lower current lightning. The procedure for calculating the risk index is described in lightning protection standards. The result determines the need for a lightning protection system and its degree of security...

Operation of early streamer emission air terminals is based on the electric characteristics of lightning formation. Lightning begins with a down-conductor which spreads in any direction. Once it approaches the objects on the ground, any of them can be struck. The objective of an external lightning protection system is to control the lightning strike point and provide the lightning current with a path to earth avoiding damage to the structure. The main feature of Early Streamer Emission (ESE) air terminals is the generation of the continuous upward leader before any other object within its...

APLICACIONES TECNOLOGICAS ft Each air terminal must be earthed using two down-conductors located outside the structure. They will preferably be on different external walls of the building. ft Each down-conductor should be installed such that its routing is as straight as possible and takes the shortest path to earth without sharp bends or upward sections. Care should also be taken to avoid crossing or running conductors in close proximity to electrical cables. When external routing is impracticable, the down-conductor may be internally routed. However, this is not recommended as it reduces...

> GUIDE FOR DESIGN AND INSTALLATION USING RODS AND MESHED CONDUCTORS Lightning protection using rods and meshed conductors is intended to share and dissipate the lightning current through a network of down-conductors and earth terminations. The elements of a lightning protection system using rods and meshed conductors are as follows: > EXTERNAL LIGHTNING PROTECTION SYSTEM • Simple rods and/or meshed conductors • Down-conductors > ROLLING SPHERE METHOD This method is based on an electrogeometric model that assumes that the last step of the downward leader can propagate in any direction. The...

APLICACIONES TECNOLOGICAS > GUIDE FOR DESIGN AND INSTALLATION USING RODS AND MESHED CONDUCTORS > MESH METHOD > RECOMMENDED MATERIALS DENOMINATION According to this method, conductors forming a mesh should be placed on the structure. The separation depends on the protection level:

Diagram showing different applications of the most common references. AT-111B This drawing is for guidance purposes only and is not intended for applying the corresponding regulations. The articles are not represented according to the same scale. AT-109B |26 AT-012G 108 LIGHTNING RODS AND ACCESSORIES 54