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Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection)

 To: ersmar@comcast.net, w1ksz@earthlink.net, towertalk@contesting.com Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection) Telegrapher9@aol.com Thu, 4 Jan 2007 04:08:15 EST
 ```Gene, does anyone run simulations or calculations on lightning strikes. A common direct stike is 100 kA with a risetime of 8 us, correct? If so, using an inductance of 200 nH/ft, the voltage drop along 1 foot of wire is 2.5 kV. And we can calculate the low frequency impedance of a ground system. Let's say it is 1 ohm. Now we have 100 kV between the tower base and earth ground. Using some ball park numbers like this we should be able to determine the currents and potentials at various points in the system. Then appropriate series Z and shunt Z can be applied to design for survival of equipment. I'm thinking of doing it via design rather than blindly by code. I suppose that there is nearly 100 years of experience contained in the codes that will lead one to success. But perhaps a good understanding of the nuances can help one to gain several dB of margin by some simple additions. Can someone steer me to some numbers on lightning? Thanks. Dave WX7G _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection), (continued) Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection), Jim Lux Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection), ersmar Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection), Telegrapher9 <= Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection), ersmar