Earthing problems

The paper discusses the various factors which affect the resistance of earth electrodes and contains a summary of the different types of electrodes in common use for obtaining an earth connection. Special reference is made to the use of deep-driven rods and the results obtained by the author using these electrodes in various parts of the country. A short description is given of existing earthing practice on high-voltage apparatus, while the methods available for providing efficient protection on low-voltage apparatus are discussed in detail. The concluding Sections deal with the need for periodic testing of existing installations and the methods to be employed in carrying out such tests, with a final plea to those in authority to give a lead in a more rational approach to this most important subject.