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Practical challenges of electrical earthing in both steady and transient states have been revisited. By analyzing the cases based on theoretical and practical aspects, engineering guidelines are proposed to develop suitable solutions. Less complicated cases can be approached with various electrode configurations such as multiple ring, antenna, crow-foot and centipede arrangements. Distributed earthing arrangements treated with backfill materials are suitable for the sites with extremely high resistive soil. Clay based backfill materials such as bentonite-mix give corrosion and erosion protection for the electrodes in highly acidic, alkaline, saline and sulfur-rich environments apart from reducing the low frequency resistance. On-rock sites such as transmission and communication towers are better approached with concrete-based earthing systems in both cases of power and lightning protection earthing. Extreme cases of soil instability have been identified and discussed. The suitability of vertical and horizontal electrode components as well as copper and steel electrodes under various soil conditions is also discoursed. For most cases, we recommend all types of earthing systems to be integrated, however, properly coordinated system of Surge Protective Devices (SPDs) should be incorporated in such integrated earthing system.

The final-year project (FYP) is considered to be one of the most important learning experiences in an engineering undergraduate education. It is mandated by engineering accreditation bodies worldwide as a compulsory module in the engineering curriculum. For most fresh graduate engineers, their final-year project experience will be the most vivid of all their recent memories when they recall their engineering education experience. This is due to the immense challenge the students face by undertaking for the very first time an individual, highly complex, open-ended research work with tight deadlines to meet and high expectations to attain on their own, albeit under the guidance of their supervisors. As such the FYPs’ delivery and assessment process offer strategic opportunities for engineering educators to add value to an undergraduate engineer’s training provided that it is designed and implemented with a clear intent. This paper documents the assessment approach adopted by School of Engineering, Taylor’s University, for the FYP module which is divided into the FYP1 and FYP2 modules covering two semesters. This assessment process is distinct from the practices at many other equivalent institutions in that it has as much as 6 assessment components for each module, assessors other than the supervisor contribute the bulk of the marks, timely feedback from assessors to students is fully integrated into the assessment process to facilitate learning and students are required to participate in a research conference which is also made into one of the assessment components. For this undergraduate conference, the students’ FYP research papers are reviewed by external reviewers from other universities and assessed and awarded marks by them. A detailed description of each assessment component followed by an evaluation of how each assessment component adds value to the students’ learning for both the FYP1 and FYP2 modules is discussed.

The value of soil resistivity is an essential pre-requisite in designing an electrical grounding system. The current practice, as advocated even by national/international standards involves taking the average soil resistivity of the site as the parameter to be considered in designing the grounding system. This study shows that average soil resistivity may lead to significant overestimation or underestimation in the designing process as the localized soil resistivity may significantly differ from the average soil resistivity of the entire site. At least 14% difference between average and localized soil resistivity were obtained base on measurements done on five locations. Therefore, it is suggested that electrical engineers who design grounding systems should first identify the locations where the components of the grounding systems will be installed. Then, the localized soil resistivity at that particular point should be measured and the sizing and geometry of the grounding electrode should be designed accordingly.

Effects of surrounding environment of grounding electrode locations on the performance of overall grounding system has been studied. Copper rods were buried at 25 different locations with various environmental settings and their respective variations in grounding resistance were monitored for up to 4 months. It was found that there is a clear dependence of grounding resistance on the condition of surrounding environment, in addition to the average soil resistivity. Installation of grounding electrodes near running waterways, huge trees as well as slopes should be avoided wherever possible as the ground resistance of electrodes in such environments may fluctuate significantly with time.

Grounding issues related to lightning currents have been addressed giving special attention to recommended practices in IEC 62305 (2010). Unambiguous recommendations are needed for the requirement of type A system or type B system or both systems for a given installation. Specifications of the length of conductors, based on the level of protection, were critically analyzed emphasizing the human risk related issues. Calculations reveal that at Level III and IV, the specified lengths of type A conductors may give step potentials, especially in highly resistive soils that may drive currents through human beings in the vicinity, exceeding lethal energy. Furthermore, specification of the limiting value of resistance for transient grounding systems may lead to hazardous situations as the difference between frequency dependent impedance and low frequency resistance may increase to very high values at Mega Hertz range where lightning energy spectrum has significant amplitude. Covering of a sizable surface area surrounding the grounding conductors with insulation material, is recommended as a practical solution to this issue.