 2 edits | reply to lutful By the way these are the conclusions of that IEEE paper.
XVII. CONCLUSIONS
It appears that whenever the utilities were faced with the choice of public safety or saving costs they chose saving costs over the safety of the public with respect to the multigrounded neutral distribution system and the modifications that were made that were beneficial to the transformer.
In order to have an electrical distribution system that is safe from the great and continuous risks of harm from stray current flowing uncontrolled over the earth in unrestrained amounts the following must be accomplished:
i. The multigrounded neutral distribution system must be eliminated and replaced by the 4-wire, see figure 20 with phase-to-phase loads or the 5-wire, see figure 16 with either phase-to-phase or phase-to-neutral loads type distribution system, which will eliminate using the earth for a return current path and will contain all the return current on an insulated conductor as specified by Zipses Law.
ii. The hazardous connection of the primary neutral to the secondary neutral is no longer needed to allow previously poorly earthed lightning arrestors to function since the ground conductor is earthed at four times per mile providing adequate earth connection for the lightning arrestors.
iii. No longer will the messenger be allowed to functioning as a messenger, a neutral and a ground conductor. The service drop conductors will consist of one, two or three phase conductors, an insulated neutral, and the messenger that can also serve as the earthing conductor only.
iv. No longer will the neutral be connected to the earth at the service disconnect and overcurrent panelboard. With a separate insulated neutral, which will be connected to earth at the transformer and a ground conductor from the transformer coming into the service disconnect and overcurrent panelboard at the residence, it will not be required to connect the neutral to the earth again at the service disconnect and overcurrent panelboard.
v. Consideration should be given to the installation of GFCIs on all 120-volt circuits that could become or could develop a neutral-to-ground fault. If the public wants to be able to enter a swimming pool or a hot tub or to take a shower without the fear of receiving an unwanted electric shock or to be a victim of an electrocution, then the public must rise up in letter writing to their Public Service Commissions and their legislators both local and federal and demand an electrical distribution system free from to flow of uncontrolled hazardous stray current.
A little background on the author for ya.
Donald W. Zipse (S'58-M'62-SM'89-F94-LF97) was graduated from the Williamson Free School of Mechanical Trades with honors where he gained practical experience in electrical construction and in power plant operation. He received his electrical engineering degree from the University of Delaware and went to work for Cutler-Hammer as an area sales engineer. He spent 16 years with ICI America, Inc in their Central Engineering Department as a company wide electrical specialist.
For the next 14 years, he was with the FMC Corporation in their Engineering Service organization, functioning as an Electrical Engineering Consultant, responsible for providing electrical design of new facilities and consulting service to the total corporation, both chemical and mechanical groups.
He is a registered Professional Engineer. He represents the IEEE on the National Electrical Code Making Panel #14, Hazardous Locations as well as the Lightning Standard NFPA 780 and is a member of the International Association of Electrical Inspectors. He serves on the National Electrical Safety Code Grounding Subcommittee.
He has served on many IEEE committees, participated in the color books (IEEE Recommended Practice), and standards groups, including the Standards Board and the Standards Boards Review Committee. He is a member of the IEEE COMAR, committee On Man And Radiation and Standards Correlating Committee #28, Non-Ionization Radiation.
Mr. Zipse received the Standards Medallion for his work in and promoting standards.
He has published countless technical papers on such diverse and controversial subjects as Unity Plus Motors, Computers, Neutral to Ground Faults, NEC Wire Tables, Health Effects of Electrical and Magnetic Fields, Measuring Electrical and Magnetic Fields, Lightning Protection Systems: Advantages and Disadvantages, the NESC and the NEC: Are Dangerous to Your Health? Electrical Shock Hazard Due To Stray Current and has participated on National Electrical Code panels and in teaching the Code.
For the last ten years, he has been President of Zipse Electrical Engineering, Inc., an electrical forensic engineering consulting firm. For the past seven years, he has been primarily involved as a forensic engineer and expert witness in cases resulting from electrical accidents and electrocutions and for the last two years he has been involved in legal cases concerning stray current and dairy cows. |