Lightning is one of the most powerful natural phenomena in the world today. Although it does not compete with Earthquakes, Hurricanes, Tornados or Tsunamis for instant devastation and loss of life, it consistently causes billions of dollars of damage a year, accumulated on a daily basis.
According to IEC specifications, you can expect a maximum lightning current up to 200 kA. In such a case, you need a surge protector that has a surge current capacity of at least half this value. Lightning is the result of a discharge between two charged areas. These can be between :
- Cloud to cloud
- Intra cloud
- Cloud to Ground
If we consider that there are on average 100 cloud to ground lightning events every second around the world, add to this the proliferation of electronics in the business and home, the global cost of lightning and surge damage is millions of dollars daily.
The magnitude of the energy in a lightning flash is not well known by most people designing protection systems. Additionally the coupling mechanism that causes the damage is not well understood by many. The lack of understanding of these two issues contributes to many of the myths that have evolved about lightning. The most significant of these myths is that "a SITE cannot survive a direct lightning strike."
- IEEE STD 142-1991 Grounding of Industrial and Commercial Power Systems.
- IEEE STD 1100-1999 Powering and Grounding Electronic Equipment
- IEEE Transactions on Electromagnetic Compatibility, Nov. 1998
- National Research Council, Transportation Research Board, NCHRP Report 317, June 1989
- International Electro technical Commission (IEC), International Standard for Lightning Protection. See: http://www.iec.ch
- Gardner RL, Lightning Electromagnetic, Hemisphere Publishing, NY NY 1991
- EMC for Systems and Installations, T. Williams and K. Armstrong, Newnes, Oxford UK, 2000.
- NATO STANAG 4236, Lightning Environmental Conditions, 1995.
Over the years I have authored numerous white papers and published articles on Lightning and Surge Protection. Below are a few of these that may be of interest. Some have been published in the ITS International and IMSA Journals.
- Lightning coupling mechanisms, the 10/350μs Waveform and Protection techniques for Wireless sites.
- Unique Problems of Surge and Generic Protection Techniques for Wireless Sites (ICLP Conference in Curitiba Brazil.
- Avoiding disaster with Zoned Protection (ISA conference & magazine article)
- Location safety Factor and its Impact of Antennae Safety with reference to direct Lightning Strikes.
- Experiences of Surge and Lightning Protection systems for ITS deployments.
- Investment in Lightning Protection for equipment survival - What cost?