Study of alternatives for replacing the intermediate interconnection rings of the down-conductors

The present article presents a study of the electrical current distribution by down-conductors after a direct lightning strike onto an air-termination system. The type of air-termination system under analysis is mesh with multiple down-conductors connected by intermediate rings. The study also proposes an alternative method in order to substitute the intermediate connection rings. Such change simplifies implementation and improves frontage aesthetics in buildings which require such systems. The methodology for the study was based on the use of inductive impedance arrangements for different dimensions of the capture subsystem mesh as defined by the Brazilian and International Standards for lightning protection systems for the quoted text. Based on the cited methodology, arrangements were made using the dimensions of the meshes according to the standards and interconnecting ring of the down-conductors, as well as without these rings, but with the dimensions of the reduced meshes and double inner ring or outer ring. These arrangements were structured in ATPDraw 6.0. This way, a positive impulse 10/350 μs was injected, using a Hiedler source. The simulation data were compared with each other, and the result of this analysis indicated that the redistribution of currents by the down-conductors is quite effective. Considering the results obtained by the present study, it was understood that the use of double inner ring or outer ring or a combination of them should be deemed as worthy of being incorporated as a valid lightning protection system technique.