Xref: utzoo comp.misc:2782 sci.electronics:3271 Path: utzoo!utgpu!water!watmath!clyde!bellcore!faline!thumper!ulysses!andante!mit-eddie!bbn!rochester!kodak!ornitz From: ornitz@kodak.UUCP Newsgroups: comp.misc,sci.electronics Subject: Re: Lightning rods. Was: Protecting computer equipment Summary: Pointed Rods Not Optimum Keywords: lightning, lightning rods, discharges, protection Message-ID: <1314@kodak.UUCP> Date: 12 Jul 88 16:02:17 GMT References: <1988Jul8.045005.17867@utzoo.uucp> <6179@aw.sei.cmu.edu> Reply-To: ornitz@kodak.UUCP (barry ornitz) Followup-To: sci.electronics Organization: Eastman Kodak Co, Rochester, NY Lines: 25 In article <6179@aw.sei.cmu.edu> rsd@ae.sei.cmu.edu.UUCP Rich D'Ippolito writes: >* Electric field theory will explain the reason for the sharp point. Several years ago, an article on the current status of lightning protection was published in the Journal of the Franklin Institute (naturally!) by scientists from one of the Arizona universities. In this article, it was shown that the sharp point is not optimum but instead an elliptical point should be used. This suggestion was backed up by simulation studies and the study of several thousand actual strikes on lightning rods. In virtually all cases, the rods were hit several inches to several feet _below_ the pointed tip. The article also debunks a number of myths about the "cone of protection" supposedly produced by a high lightning rod and also about the neutralization of space charges by lightning rods. If there is enough interest, I can dig up the date of the issue. Barry WA4VZQ ----------------- | ___ ________ | | | / / | | Dr. Barry L. Ornitz UUCP:...!rochester!kodak!ornitz | | / / | | Eastman Kodak Company | |< < K O D A K| | Eastman Chemicals Division Research Laboratories | | \ \ | | P. O. Box 1972 | |__\ \________| | Kingsport, TN 37662 615/229-4904 | | -----------------