6. What’s the Good lightning protection system should be ?
Answer: The Lightning Protection system can be divided into three major parts as follows:
1. Lightning Air-terminal.
2. Down Conductor / Down Lead.
3. Lightning Ground.
1. Lightning Air-terminal, in the event of lightning strike if we can not stop it form happen actually we want to choose the lightning to be strike at the lightning air-terminal point as for the safety, as the reason we must install the lightning air-terminal at the highest point of the structure as we can, for example install the lightning air-terminal above the highest point of the building structure e.g. TV antenna, radio antenna, water tank and etc and should be at lease 2 meters up above those highest object points (as Stabil standard), the lightning air-terminal should made with the good conductor metal and great withstand with the melting e.g. copper bar, stainless steel bar, tin plated copper bars, or other conductive materials and can also consider by where the lightning air-terminal to be installed e.g. if install near the sea should use materials which can good withstand the corrosion or can consider by budget of the installation and etc.
To install the lightning air-terminal the lightning air-terminal must not has any part to connect with the building structure ( Isolate the system ) this is to mitigate the effects of lightning which may effect to the building and electrical system in the building itself. There should has the sharp points due to the sharp points will have better ability to transfer ions to the air, a good lightning air-terminal should has a diameter not less than 3 / 8 inch, and not less than 10 inches long (standard UL96) in order to be able to handle large amount of the lightning strike currents well.
2. Down Conductor / Down Lead should be conducted with good electrical conductivity wire, melting resistant, such as THW wire, bare copper wire, steel wire or other conductor which has cross-section area not less than 70 mm². (according Stabil standard) and can be determine from the area of installation for example, if near the sea should use material with a good corrosion resistance or considering from the difficulty of installation or the budget of installation and etc.
The wiring of down conductor from the Lightning air-terminal to the lightning ground rod should has the shortest route and as possible, this is as to minimize the Flash over to the side of the building.
Wiring the down conductors should use the Down-lead Support with Ceramic insulators type as to hold the down lead wire to the lightning ground rod with separately from the main building structure.
3. Lightning Ground, as you can see from the previous description on the topic of Deep earth grounding principle works, currently the use of Lightning Air-terminals on the market now there’re many types of them such as the Faraday type, the Early Streamer Emission type, the Radio Active type, the Umbrella type and etc. as experienced STABIL would recommended the Faraday air-terminal type better this is due to the Faraday air-terminal is typically worked well with low cost, the protection angle about 45 degrees (measured from the tip of the air-terminal ) from the past found that when the Faraday air-terminal combined to work together with the deep earth grounding system the efficiency and the angle of lightning protection will be increased much more this is because of the lightning air-terminal can electro-statically exchange the ions between the air and the lightning air-terminal tip better with the a deep grounding system.
To Install the lightning protection systems in every join points from the Lightning Air-terminal through the down conductors down to the lightning ground rods will be connected by using Exothermic Welding (metal meat together) as for the best of huge amount of lightning currents transfer in a very short duration with maximum efficiency, and this will make the less effects of the lightning strike to the building and electrical system as well.