1、MIL-HDBK-419A29 DECEMBER 1987SUPERSEDINGMIL-HDBK41921 JANUARY 1982MILITARY HANDBOOKGROUNDING, BONDING, AND SHIELDINGFORELECTRONIC EQUIPMENTS AND FACILITIESVOLUME 1 OF 2 VOLUMESBASIC THEORYAMSC N/A EMCS/SLHC/TCTSDISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimitedProvided
2、by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-DEPARTMENT OF DEFENSEWASHINGTON DC 20301MIL-HDBK-419AGROUNDING, BONDING, AND SHIELDING FOR ELECTRONIC EQUIPMENTS
3、AND FACILITIES1. This standardization handbook was developed by the Department of Defense in accordance withestablished procedure.2. This publication was approved on 29 December 1987 for printing and inclusion in the militarystandardization handbook series. Vertical lines and asterisks are not used
4、in this revision to identify changeswith respect to the previous issue due to the extensiveness of the changes.3. This document provides basic and application information on grounding, bonding, and shieldingpractices recoin mended for electronic equipment. It will provide valuable information and gu
5、idance topersonnel concerned with the preparation of specifications and the procurement of electrical and electronicequipment for the Defense Communications System. The handbook is not intended to be referenced in purchasespecifications except for informational purposes, nor shall it supersede any s
6、pecification requirements.4. Every effort has been made to reflect the latest information on the interrelation of considerationsof electrochemistry , metallurgy, electromagnetic, and atmospheric physics. It is the intent to review thishandbook periodically to insure its completeness and currency. Us
7、ers of this document are encouraged to reportany errors discovered and any recommendations for changes or inclusions to: Commander, 1842 EEG/EEITE,Scott AFB IL 62225-6348.5. Copies of Federal and Military Standards, Specifications and associated documents (including thishandbook) listed in the Depar
8、tment of Defense Index of Specifications and Standards (DODISS) should beobtained from the DOD Single Stock Point: Commanding Officer, Naval Publications and Forms Center, 5801Tabor Avenue, Philadelphia PA 19120. Single copies may be obtained on an emergency basis by calling(AUTOVON) 442-3321 or Are
9、a Code (215)-697-3321. Copies of industry association documents should beobtained from the sponsor. Copies of all other listed documents should be obtained from the contractingactivity or as directed by the contracting officer.Provided by IHSNot for ResaleNo reproduction or networking permitted with
10、out license from IHS-,-,-MIL-HDBK-419APREFACEThis volume is one of a two-volume series which sets forth the grounding, bonding, and shielding theory forcommunications electronics (C-E) equipments and facilities. Grounding, bonding, and shielding are complexsubjects about which in the past there has
11、existed a good deal of misunderstanding. The subjects themselves areinterrelated and involve considerations of a wide range of topics from electrochemistry and metallurgy toelectromagnetic field theory and atlmspheric physics. These two volumes reduce these varied considerationsinto a usable set of
12、principles and practices which can be used by all concerned with, and responsible for, thesafety and effective operation of complex C-E systems. Where possible, the Principles are reduced to specificsteps. Because of the large number of interrelated factors, specific steps cannot be set forth for ev
13、ery possiblesituation. However, once the requirements and constraints of a given situation are defined, the appropriatesteps for solution of the problem can be formulated utilizing the principles set forth.Both volumes (Volume I, Basic Theory and Volume II, Applications) implement the (Grounding, Bo
14、nding, andShielding requirements of MIL-STD-188-124A which is mandatory for use within the Department of Defense.The purpose of this standard is to ensure the optimum performance of ground-based telecommunicationsequipment by reducing noise and providing adequate protection against power system faul
15、ts and lightningstrikes.This handbook emphasizes the necessity for including considerations of grounding, bonding, and shielding in allphases of design, construction, operation, and maintenance of electronic equipment and facilities. Volume 1,Basic Theory, develops the principles of personnel protec
16、tion, fault protection, lightning protection,interference reduction, and EMP protection for C-E facilities. In addition, the basic theories of earthconnections, signal grounding, electromagnetic shielding, and electrical bonding are presented. The subjects arenot covered independently, rather they a
17、re considered from the standpoint of how they influence the design ofthe earth electrode Subsystem of a facility, the selection of ground reference networks for equipments andstructures, shielding requirements, facility and equipment bonding practices, etc. Volume I also provides thebasic background
18、 of theory and principles that explain the technical basis for the recommended practices andprocedures; illustrates the necessity for care and thoroughness in implementation of grounding, bonding, andshielding; and provides supplemental information to assist in the solution of those problems and sit
19、uations notspecifically addressed.In Volume II, Applications, the principles and theories, including RED/BLACK protection, are reduced to thepractical steps and procedures which are to be followed in structural and facility development, electronicengineering, and in equipment development, These appl
20、ications should assure personnel equipment andstructural safety , minimize electromagnetic interference (EMI) problems in the final operating system; andminimize susceptibility to and generation of undesirable emanations. The emphasis in Volume II goes beyonddevelopment to assembly and construction,
21、 to installation and checkout, and to maintenance for long term use.Four appendices are provided as common elements in both volumes. Appendix A is a glossary of selected wordsand terms as they are used herein, If not defined in the glossary, usage is in accordance with Federal Standard1037, Glossary
22、 of Telecommunication Terms. Appendix B is a supplemental bibliography containing selectedreferences intended to supply the user with additional material. Appendix C- contains the table of contents forthe other volume. Appendix D contains the index for the two-volume set.Provided by IHSNot for Resal
23、eNo reproduction or networking permitted without license from IHS-,-,-Paragraph1.11.21.31.41.51.5.11.5.21.5.31.61.72.12.1.12.1.22.1.32.1.42.22.2.12.2.22.2.2.12.2.2.22.2.32.32.3.12.3.22.3.32.42.4.12.4.22.4.2.12.4.2.22.52.5.12.5.22.5.3MIL-HDBK-419ATABLE OF CONTENTSCHAPTER 1- FACILITY GROUND SYSTEMGENE
24、RAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .APPLICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .REFERENCED DOCUMENTS. . . . . . . . . . . . . . . . . . . . . . . .
25、. . . .DESCRIPTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Facility Ground System . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Grounding and Power Distribution Systems . . . . . . . . . . . . . . . . . . . . .Electrical Noise in Communications Systems . . . . .
26、. . . . . . . . . . . . . . .BONDING, SHIELDING, AND GROUNDING RELATIONSHIP . . . . . . . . . . .GROUNDING SAFETY PRACTICES . . . . . . . . . . . . . . . . . . . . . . . . .CHAPTER 2- EARTHING AND EARTH ELECTRODE SUBSYSTEMOBJECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . .Lightning Di
27、scharge . . . . . . . . . . . . . . . . . . . . . . . . .Fault Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . .Noise Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . .Summary of Requirements . . . . . . . . . . . . . . . . . . . . . . .RESISTANCE REQUIREMENTS . . . . .
28、 . . . . . . . . . . . . . . . . . . . .General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Resistance to Earth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .National Electrical Code Requirements . . . . . . . . . . . . . . . . . . . . .Department of Defense Communic
29、ations Electronics Requirements . . . . . . . . .Lightning Require meats . . . . . . . . . . . . . . . . . . . . . . . . . . . . .SOIL RESISTIVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Typical Resisti
30、vity Ranges . . . . . . . . . . . . . . . . . . . . . . . .Environmental Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MEASUREMENT OF SOIL RESISTIVITY . . . . . . . . . . . . . . . . . . . . . . .General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Measurem
31、ent Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . .One-Electrode Method . . . . . . . . . . . . . . . . . . . . . . . . . . .Four-Terminal Method . . . . . . . . . . . . . . . . . . . . . . . .TYPES OF EARTH ELECTRODE SUBSYSTEMS . . . . . . . . . . . . . . . . . . . .General . .
32、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Ground Rods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Buried Horizontal Conductors. . . . . . . . . . . . . . . . . . . . . . . . . . .Page1-11-11-11-11-21-21-31-41-51-52-12-12-22-22-22-52-52-52-52-52-52-72-72-7
33、2-72-82-82-82-82-132-152-152-152-15iProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-HDBK-419ATABLE OF CONTENTS (Continued)Paragraph2.5.42.5.52.5.62.5.72.5.82.5.92.62.6.12.6.1.12.6.1.22.6.22.6.2.12.6.2.22.6.2.32.6.2.42.6.32.6.42.6.4.12.6.4.22.6.4.
34、32.72.7.12.7.22.7.2.12.7.2.22.7.2.32.7.32.82.8.12.8.1.12.8.1.22.8.1.2.12.8.1.2.22.8.1.2.32.8.1.32.8.22.8.2.12.8.2.22.8.2.3Grids . . . . . . . . . . . . . .Plates . . . . . . . . . . . . . .Metal Frameworks of Buildings . . .Water Pipes . . . . . . . . . . .Incidental Metals . . . . . . . . .Well Cas
35、ings . . . . . . . . . . .RESISTANCE PROPERTIES . . . . .Simple Isolated Electrodes . . . . .Driven Rod . . . . . . . . . . .Other Commonly Used Electrodes .Resistance of Multiple Electrodes . .Two Vertical Rods in Parallel . . .Square Array of Vertical Rods . .Horizontal Grid (Mesh). . . . . .Verti
36、cal Rods Connected by a GridTransient Impedance of Electrodes .Effects of Nonhomogeneous (Layered) EarthHemispherical Electrode . . . . . . . .Vertical Rod . . . . . . . . . . . . .Grids . . . . . . . . . . . . . . . . .MEASUREMENT OF RESISTANCE-TO-EARTHIntroduction . . . . . . . . . . . . . .Fall-o
37、f-Potential Method. . . . . . . . .Probe Spacing . . . . . . . . . . . .Extensive Electrode Subsystems. . . . .Test Equipments . . . . . . . . . . .Three-Point (Triangulation) Method . . . .OTHER CONSIDERATIONS . . . . . . . .Surface Voltages Above Earth Electrodes .Step Voltage Safety Limit . . . .
38、 . . .Step Voltages for Practical Electrodes . .Flush Vertical Rod . . . . . . . . .Buried Vertical Rod . . . . . . . . .Buried Horizontal Grid. . . . . . . .Minimizing Step Voltage . . . . . . . .Heating of Electrodes . . . . . . . . . .Steady State Current . . . . . . . . .Transient Current. . . .
39、 . . . . . . .Minimum Electrode Size . . . . . . . .OF ELECTRODES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40、 . . . . . . . . . . . . . . . . . . . . . . . . . . .,.Page2-152-152-162-162-162-162-172-172-172-232-232-232-272-292-302-322-322-322-332-332-352-352-352-362-422-452-462-472-472-472-492-492-532-552-562-572-572-572-59iiProvided by IHSNot for ResaleNo reproduction or networking permitted without licen
41、se from IHS-,-,-MIL-HDBK-419ATABLE OF CONTENTS (Continued)Paragraph2.9 ELECTRODE ENHANCEMENT . . . . . . . .2.9.1 Introduction . . . . . . . . . . . . . . .2.9.2 Water Retention . . . . . . . . . . . . .2.9.3 Chemical Salting . . . . . . . . . . . . .2.9.4 Electrode Encasement . . . . . . . . . .2.9
42、.5 Salting Methods. . . . . . . . . . . . . .2.10 CATHODIC PROTECTION . . . . . . . . . .2.10.1 Introduction . . . . . . . . . . . . . . .2.10.2 Protection Techniques . . . . . . . . . . .2.10.3 Sacrifical Anodes. . . . . . . . . . . . .2.10.4 Corrosive Atmospheres . . . . . . . . . .2.11 GROUNDING
43、IN ARCTIC REGIONS . . . . . .2.11.1 Soil Resistivity . . . . . . . . . . . . . .2.11.2 Improving Electrical Grounding in Frozen Soils2.11.2.1 Electrode Resistance . . . . . . . . . .2.11.2.2 Installation and Measurement Methods . . .2.11.2.2.1 Electrode Installation . . . . . . . . .2.11.2.2.2 Backf
44、ill . . . . . . . . . . . . . . .2.123.13.23.33.43.53.5.13.5.23.63.6.13.6.23.6.33.6.3.13.6.3.23.6.3.33.6.3.43.73.83.8.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
45、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
46、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .CHAPTER 3- LIGHTNING PROTECTION SUBSYSTEMTHE PHENOMENON
47、OF LIGHTNING . . . . . . . . . . . . . . . . . . . . . . . .DEVELOPMENT OF A LIGHTNING FLASH . . . . . . . . . . . . . . . . . . . . . .INFLUENCE OF STRUCTURE HEIGHT . . . . . . . . . . . . . . . . . . . . . . .STRIKE LIKELIHOOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ATTRACTIVE AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . .Structures Less Than 10
