Amateur Radio Station Grounding and Lightning …

1 Amateur Radio Station Groundingand Lightning ProtectionAmateur Radio Station Grounding and Lightning ProtectionDisclaimer:This document, associated technical descriptions and design information comprise a W5 BWC Electronics project done exclusively for John L. KeithW5 BWC. This is an original work of W5 BWC Electronics intended to function properly and be accurately presented as described herein; however, nopart of this project is offered for sale, presented to be free of patent infringements, or represented to be fit for any particular use. Any public use of thisinformation is offered for educational purposes only, as a description of a personal project. Any and all liability of its' use is the sole responsibility of Rev 0 May 4th 2004, Independence, Mo, during a severe thunderstorm Photo by Mark Electronics9108 FM 1972 Gilmer, TX Radio Station Grounding and Lightning ProtectionPrefaceGrounding and Lightning protection are critical to the safe and legal operation of an Amateur Radio from the human, dwelling, and equipment aspects; legal from the city or regulatory codes, ordinancesand laws.

2 This simple sounding topic is quite complex in theory and practice, fraught with misunderstand-ings, legal liability issues and confusing regulatory topics, however, do not lack for publications, documents, studies or opinions. The purpose of this (yetanother) document is to provide the technically savvy Amateur Radio Operator the ability to understand thecritical need for Lightning protection and Grounding find much of the published material is too little or too much theory for the average Amateur Radio a practical implementation standpoint the subject is so complex and burdened with minute (but critical)details that much of the material simply states - specific installations each require careful attention to detail,design and implementation. Even more frustrating to Amateur Radio operators is the lack of support fromdistributors or manufacturers - probably due to legal liability concerns.

3 The common response is we are notgrounding experts and so refer to EIA/TIA222 (for tower erection and Grounding ) or the NEC/UL standards .The better, but sales biased, information is from protection equipment document is my attempt to first; present sufficient theory for an Amateur Radio operator to understandthe detailed analysis necessary for proper Grounding and protection , and secondly present sufficient materialand examples to allow implementation of that theory. Recommendations are based on the obscure codes andstandards - at least seemingly so to Amateurs - without a bias to any particular products or , practical and common sense approaches are referenced from the Amateur Radio community, that haveestablished document supercedes Lightning and Amateur Radio that was distributed in 1989.

4 Both document swere done originally for a Longview East Texas Amateur Radio club program. Preparing for a repeatpresentation in 2011, I updated the material and decided that others might benefit from this hand-out also, soI published it on my web document is available in PDF format, , with referencehyperlinks use of this document is for educational purposes only. While this document is based on information fromauthoritative sources, it still is my interpretation thereof and not a legal document for the construction, design,operation or installation of any system for which local or federal codes or laws is the individual user s responsibility to ensure Lightning protection and/or Amateur Radio stationinstallation complies with local regulatory codes and noticeThis document may be copied, distributed and referenced freely for non-profit uses.

5 It is requested credit begiven, especially for the material and images with third party credits noted, when so Electronics9108 FM 1972 Gilmer, TX Radio Station Grounding and Lightning ProtectionTable of ContentsPageIntroduction5 Description of lightning6 Lightning overview6 Formation of Lightning7 The Lightning flash8 Lightning model10 Inductively coupled lightning12 Electro-statically coupled lightning13 Air terminal13 Description of ground14 The myth of ground14 The earth as ground15 Measuring and effecting ground resistance17 Step potential17 Ground conductor bonding and galvanic corrosion18 Bonding individual ground terminals19 Practical Grounding methods22 Improper Grounding can cause more damage than none22 Single point ground22 ARS earth terminal27 Bonding to earth terminal28 Isolating single point ground from strike current29 Disconnect30 Conclusion33 References34 Appendix35W5 BWC Electronics9108 FM 1972 Gilmer.

6 TX Radio Station Grounding and Lightning ProtectionList of Characteristics and Characteristics - strike series - selected inductance29 List of of Eucalyptus damaged 8/20 Lightning model rod density surrounding ground rod blow tower ground fault - improper ground fault - properly diagram of properly grounded protector point ground entrance bulk to ground ground entry ground water fragments from and tower Lightning tree strike at west tree strike at front disconnect panel32W5 BWC Electronics9108 FM 1972 Gilmer, TX Radio Station Grounding and Lightning ProtectionIntroductionThis document is intended as an introduction to Amateur Radio Station Grounding and Lightning reference material quoted is from listing agencies and recognized researchers.

7 While this subject appearssimple, it is actually quite complex and requires a dedicated effort to understand and implement this document will simplify the subject s complexities and provide a basic understanding ofgrounding and Lightning protection , while also providing realistic approaches for the average Amateur are in place that are based on NEC (National Electrical Code), UL (Underwriters Laboratories) andNFPA (National Fire Prevention Association) codes and standards, and often appear in local city codes. It isthe reader s responsibility to ensure all such legal requirements are satisfied by their installation. Thisdocument is offered as an introduction and guide to assist one in understanding and implementing therequirements of local codes and good engineering document s title begins with Grounding but the text begins with a description of Lightning .

8 As withany engineering problem, defining the problem to be solved is the first step and while Grounding must satisfyother requirements, Lightning protection may be the most complex aspect. Certainly, the Lightning phenome-non is a complex subject in its own right and one under continual scientific study. A description of lightningis presented to familiarize the reader with the phenomenon and define the problem of Lightning , the myth of ground is explored. While earth ground does indeed exist, so do our misunderstandingsof it. In electronics, ground is considered to be a common point, a point of zero potential and an infinite sinkof electrons. In reality, most points we consider grounded are far from this perfect state. Earth ground isdescribed in the context of Lightning protection , safety and operational performance.

9 Included are descrip-tions of bonding and galvanic isolation which are critical to effective Grounding . Also addressed areregulatory and agency Grounding , practical Grounding methods are presented that are based on the foregoing considerations. In thecontext of a practical approach, risk management for Amateur Radio Station Lightning protection is ground implementation, meeting regulatory codes and operational performance are also approach does NOT imply a haphazard or careless approach, but rather one that emphasizes detailsand options for protection and appendices support and expand on the text. I suggest the references be studied for a more in depth un-derstanding of this topic, even though some of the material can become somewhat overwhelming.

10 Point-in-case Mil standardMIL-HDBK-419A volumes 1 and 2 are exceptional for factual, engineering based infor-mation but total some 1200 the use of alphanumeric superscripts throughout the text. Numeric superscripts refer to References included at the end of the document. Alpha superscripts refer to Appendices also locatedat the end of the Electronics9108 FM 1972 Gilmer, TX Radio Station Grounding and Lightning ProtectionFigure 1. Aug 23, 2003 - Toronto thunderstorm takenby John R. Southern from Toronto, Ontario, CanadaDescription of LightningLightning overview All creatures on the surface of the earth have experi-enced Lightning , I don t remember where I read this,but how order to design and implement Lightning protectionand Grounding systems, we need to first define thethreat.