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How to calculate the protection range of lightning tower

Author:admin Time:2018-11-12 10:42:00
What kinds of calculation methods are there for the protection range of lightning arresters? This paper summarizes the calculation methods commonly used in the protection range of lightning arresters in the Electrician's Home. I hope it will be helpful to all of you.
At present, the formulas for calculating the protection range of lightning rods in different countries in the world are different in form. Generally, there are several methods for calculating the protection range of lightning rods as follows:
1. Broken line method: that is, the protection range of a single lightning rod is a broken line cone.
2. Curve method: that is, the protection range of a single lightning rod is a curve cone.
3. Straight-line method: the point of lightning rod is used as the vertex to make a depression angle to determine, the building with explosion danger is used 45 degree angle, and the general building is used 60 degree angle, essentially the protection range is straight cone.
Since 1983, China has formally formulated its own lightning protection standards. At present, China's building lightning protection code GB50057-94 also adopts the rolling ball method recommended by the International Electrotechnical Commission (IEC) as the calculation method of lightning rod protection range.
According to the calculation method of lightning rod protection range, the commonly used calculation methods of lightning rod protection range mainly include folding line method and rolling ball method. Therefore, the calculation of "folding line method" and "rolling ball method" are preliminarily analyzed and discussed. It is concluded that the main characteristic of "folding line method" is intuitive design and calculation. It is simple and economical, but the height of buildings over 20m is not applicable. The main feature of "rolling ball method" is that it can calculate the protection range of lightning rod (belt) and grid combination, but the calculation is relatively complex and the investment cost is relatively large.