Study on the usage of structural building as main lightning protection

Abstract

In country such as Malaysia, lightning occurrence is very common and it's capable in causing major damage and interruption to power systems utilities. Thus a highly compatible lightning protection system is crucial in order to ensure human safety and the longevity of the equipments. This study will look into the analysis and design of lightning protection systems for the buildings. One part of the lightning protection system is the down conductor. Down conductor provides the path for high surge from lightning strike on air terminal to the earthing systems. There are conflicting statements in some standards namely IEEE STD 142:1991, FAA-STD-019d and BS 7430:1998, on whether or not the structural steelwork can become a part of the down conductor. However these standards only provide some guidelines and reasoning for the design of lightning protection system for building's structure. So far no experimental and simulation studies have been conducted in this topic. This preliminary study will present experimental result of a small scale concrete beam and copper under impulse test. Two remote earths were selected to provide comparative study on the effect of having two different remote earths. The voltage and current traces for both were described. Impulse impedance obtained for the concrete beam and copper also shown in this study. It was found that the beam is not preferable to be used as down conductor strip compared to the copper due to higher impedance in the beam structure, which can contribute to the delay of high current to be discharged to the earth.