Answer Happy

ci. Draw a plan view showing the air-termination network mesh and the down conductor arrangement for a residential building which is 40 m tall, 20 m wide and 30 m long according to Class III Lightning Protection System (LPS) of BSEN 62305. With the use of the tables shown in Appendix 5, indicate the size of the air-termination network and positions of all down conductor in the plan view. (6 marks)
Appendix Table 2 - Maximum values of rolling sphere radius, mesh size and protection angle corresponding to the class of LPS Class of LPS Rolling sphere radius Protection method Mesh size w m Protection angle מח 1 20 5x5 11 30 See Figure 1 below HII 10 10 15 15 20 x 20 45 IV 60 80 70 60 50 (") Class of LPS 40 30 IV III 20 10 0 02 10 20 30 40 50 60 him) IEC 2016/10 NOTE 1 Not applicable beyond the values marked with Only rolling sphere and mesh methods apply in these cases NOTE 2 h is the height of air-termination above the reference plane of the area to be protected NOTE 3 The angle will not change for values of below 2 m. Figure 1 - Protection angle corresponding to the class of LPS Table 4 - Typical preferred values of the distance between down-conductors according to the class of LPS Class of LPS Typical distances 1 10 II 10 III 15 IV 20 End of Paper 10