The installation spacing of the lightning rod on the top of the roof can be as well understood as the spacing between the supports of the lightning arrester and the fixed point
The lightning protection range of the lightning protection belt is determined by using the rolling ball method, and lightning protection grid is designed by the principle of Faraday cage, therefore, in the design of lightning protection grid can not blindly pursue the height of grid lightning. In practice. A parapet with flat roof, its width is less than 24m, only a lightning belt along the upper part of the parapet, width is greater than 24m, shall be on the roof between the two installation of lightning protection belt with the connecting bar, the connecting bar spacing is not greater than 20m.
For the first time the provisions of lightning lightning current parameters building lightning protection standard GB5005794: one type of 200KA; two 150KA; three 100KA. The International Electrotechnical Commission Standard IEC61312 "lightning electromagnetic pulse protection" will be the first threat level protection of lightning current value is 200KA, waveform was 10/350 s, more than the value of roughly 1%, that is, 99% of the lightning strike are included.
No parapet roof houses, its width is less than 20m, only a lightning strip on the roof, the width is greater than 20 meters, with the installation of connecting bar spacing is not greater than 20M (three buildings). Fit the size of the lightning grid.
