FIRST PHASE OF DISCHARGE
Visuality of a lightning discharge is a kind of luminous from clouds to the ground. In between this route luminous light deflates and within the microseconds second flux follows the previous one which creates pre discharge. It also called pilot discharge as well. As the clouds overhead is negative, pilot discharges deflate before reaching the ground. Edge of the pilot discharges are close to the ground however splashes are 30-40m length and are independent from the ground surface.
SECOND PHASE OF DISCHARGE
Movement of the pilot flux increases the electrical field strength of the ground. This creates a positive discharge from ground to the air called ground discharge and it continues until reaches to the clouds from the way of pilot discharge. (It is the reason of our curious whether the lighting goes from ground to air or air to ground). This phase is called second phase of discharge and active lighting rod moves in this stage. Increasing the concentrated electrical filed, lighting rods pass the all main discharge through them instead of elsewhere.
THIRD PHASE OF DISCHARGE
Now ground discharge reaches to the clouds. By following the ionized way happened with ground discharge, Clouds discharge the whole flux through this way. Increased Electrical field strength of the active lighting rod in second phase takes the all discharge and transmits to the ground.
LIGHTNING PROTECTION METHODS
This is the most classical way of protection from a lightning. Mostly useful for tall constructions like towers, chimneys, light houses where it is not safe for wide constructions. Conductive rod creates a protection area with 45 degrees from its top point. From top to the ground with 45 degrees conical area called Franklin Cone. Radius of the protection area is equal to the height of top point of the rod. Today they are still popular for narrow and high constructions.
Invention of Michael Faraday is useful to protect the wide areas, constructions from the lightning. It’s the advanced version of Franklin Rod. Depending on the protection activity, by extending the width and length of the conductive materials plus mantling the rods onto their intersection points those connected to the ground, transmits the electrical strength to the ground. All these conductive materials are connected to the surrounding material. System is still in use however due to the price disadvantage and protection failure of the outer space than the building it is not so common.
ACTIVE LIGHTNING RODS
WORKING PRINCIPLE OF ACTIVE LIGHTINING RODS
Active lightning rods are also known early streamer emission systems and called ESE Active Lightning Rods. Principle of the active lightning rods is rising up the electrical field strength depending on the electrical charge or the air. Thus protection from negative or positive lighting kinds is provided. The latest version of said protection is quite common nowadays in all ever the World. Main working principle is to catch and forward the lightning into the ground safely before it discharges to the ground directly. In this respect lightning capture rate (∆T) is very important for a lightning rod performance. Due to created electrical field in the air, active lightning rod is preparing a guide way to the ground for lighting and as they do not ionize the air, all unnecessary discharge risks are eliminated. Active lightning rods (ESE) obtain their energy from the electrostatic and electromagnetic Field intensity changes.
AKTİF PARATONERLERİN ÖZELLİKLERİ
Aktif paratonerlerin en önemli özellikleri, kurulmuş oldukları yerlerde dairesel alanda yıldırımdan etkin bir koruma sağlamalarıdır. Dolayısıyla uygun bir projelendirme ile hem ekonomik hem de etkin yıldırımdan korunma aktif paratonerler ile yapılır. Aktif paratoner sistemlerinde paratoner tesisinden toprağa tek noktadan iniş yeterli olmaktadır. Bununla birlikte çok yüksek binalarda her 20 m’de bir yatayda binanın dış yüzeyince iletkeni döşemek gerekir ki bu sisteme de “kuşaklama” denir. Aktif paratoner sisteminin de tıpkı faraday kafesi gibi topraklamasının son derece iyi olması gerekmektedir. Aktif paratonerlerin kullanım alanları :Tüm binalara, açık alanlara rahatlıkla ve çeşitli şekillerde uygulaması yapılan aktif paratonerler okullar, hastaneler, fabrika binaları, baz istasyonları, akaryakıt dolum ve satış istasyonları, havaalanları, stadyumlar, apartmanlar, yazlık siteler, cami, kilise ve havralar gibi yaşam alanımızda bulunan tüm bina ve tesislerde kullanılmaktadır.