Advantages

The advantages of a triggered leader

  • Improved performance and efficiency
  • Reduced installation cost
  • Less raw materials, reduced carbon footprint
  • Improved aesthetics

SafeStrike generates an early and continuous upward leader using the natural build up in ambient electric field during a thunderstorm and imminent to a lightning strike. The rapid ascent of its upward leader to capture the downward leader means SafeStrike provides the most efficient form of protection for a structure or building. No power source is required.

Technical explanation of SafeStrike

  1. During the build up to a lightning strike the electric field around the SafeStrike finial rises to several thousand kilovolts. This static charge flows from the finial, through the top winding of the pulse transformer and charges the capacitor.
  2. When the voltage across the capacitor reaches the breakdown voltage of the gas discharge tube, the latter conducts and the charge from the capacitor flows as current into the bottom winding of the pulse transformer.
  3. This change of current in the lower winding of the pulse transformer causes a high voltage to be induced. This is multiplied by the turns ratio of the upper/lower windings of the transformer and so a predetermined and sufficient voltage will appear on the finial of the SafeStrike. This is sufficient to encourage an upward leader discharge which creates the initiation advance. It is insufficient to break over the external spark gap formed by the casing of the SafeStrike. 4. When the return strike current hits the SafeStrike the voltage is sufficient to ionise the external spark gap and the main current passes safely through the casing to the downward conductor to earth.

With the exception of the capacitor charging in stage 1, all of the above steps happen in virtually instantaneous succession. The time advantage of the initiation advance is in the range of 50-60 microseconds in comparison to a simple finial or striking plate. To put the advantage into perspective, a lightning strike has a 200-250 microsecond time duration.