Protective device estimation is a challenging task because there are numerous protective devices present in a typical distribution system. Among various protective devices, auto-reclosers and fuses are the main overcurrent protection on distribution systems. Operation of a protective device in response to a particular fault condition depends upon the protective device’s operating behavior and coordination of various such protective devices. This thesis presents the design and implementation of a protective device estimation algorithm which helps in identifying which protective devices have operated to clear a short circuit condition. The algorithm uses manufacturer’s device details, power quality data measured from substation monitoring devices and power system event features estimated using existing DFA algorithms. The proposed technique can be used to evaluate coordination of these protective devices and helps in locating a fault in a distribution system feeder. This approach is independent of feeder topology and could be readily used for any distribution system. The effectiveness of this algorithm is verified by simulated and actual test data. Suggestions are included for future research and application by electric utilities.

Master of Science / Department of Electrical and Computer Engineering / Medhat M. Morcos / The inclusion of Selective Coordination in the NEC since the 2002 revision and the expansion of applications for which coordination of Over-current Protective Devices is required have resulted changes in design approaches for electrical engineers. In order to meet the requirements of the NEC regarding Selective Coordination for secondary power systems within buildings, often, upstream protective devices need to be held-in to a short-circuit condition, thus increasing the Arc Flash Energy. Electrical engineers must understand the many aspects of Selective Coordination when approaching a project from the very beginning. Decisions made by the engineer regarding Selective Coordination will have influence on project cost, project timeline, robustness of the electrical equipment, and safety of personnel working near or on the electrical equipment. The main objectives of this report are to convey an understanding of the following: recent changes in requirements for Selective Coordination, implications of short-circuit analysis, impacts of selectively coordinated systems on Arc Flash Energy, risks surrounding Arc Flash Hazards, and design processes regarding Selective Coordination.

O trabalho apresenta uma metodologia aplicável à coordenação de dispositivos de proteção contra surtos em sistemas de corrente alternada de baixa tensão. Esta tem como base a adequação dos níveis de isolamento e imunidade dos equipamentos elétricos e eletrônicos e de energia absorvida pelos dispositivos de proteção. A principal motivação está relacionada aos critérios de segurança e confiabilidade requeridos por instalações nucleares, em que a coordenação da proteção contra surtos assume um importante papel. Uma metodologia interativa é implementada visando otimizar o processo de análise e especificação dos dispositivos de proteção, considerando a adoção de métodos analíticos e numéricos. Modelos de equipamentos elétricos e eletrônicos, quando submetidos a surtos de tensão e corrente, além dos dispositivos de proteção contra surtos, são implementados no simulador de transitórios eletromagnéticos - ATP. Destacam-se nestes estudos, as análises de configurações e arranjos do sistema elétrico, assim como seus parâmetros, a influência destes na configuração ou arranjo ótimo dos dispositivos de proteção, além do atendimento aos requisitos das normas aplicáveis. / The work presents a methodology regarding to low-voltage surge protective device coordination. This is based on adequacy of the isolation and immunity level of electrical and electronic equipment and the energy absorbed by the protective devices. The main motivation is related to the required nuclear plant reliability and safety criteria, in whose the surge protection coordination can assume an important role. An interactive methodology is carried out to optimize the analysis and the protection device specification, considering the adoption of analytical and numerical methods. Electrical and electronic equipment models, when submitted to voltage and current surges, in addition to surge protective devices, are implemented in the electromagnetic transient simulator - ATP. In these studies, the analysis of electrical system configurations and arrangements, as well as their parameters, and their influence on the configuration or optimum protective device arrangement, besides compliance with the requirements of applicable standards are highlighted.

O trabalho apresenta uma metodologia aplicável à coordenação de dispositivos de proteção contra surtos em sistemas de corrente alternada de baixa tensão. Esta tem como base a adequação dos níveis de isolamento e imunidade dos equipamentos elétricos e eletrônicos e de energia absorvida pelos dispositivos de proteção. A principal motivação está relacionada aos critérios de segurança e confiabilidade requeridos por instalações nucleares, em que a coordenação da proteção contra surtos assume um importante papel. Uma metodologia interativa é implementada visando otimizar o processo de análise e especificação dos dispositivos de proteção, considerando a adoção de métodos analíticos e numéricos. Modelos de equipamentos elétricos e eletrônicos, quando submetidos a surtos de tensão e corrente, além dos dispositivos de proteção contra surtos, são implementados no simulador de transitórios eletromagnéticos - ATP. Destacam-se nestes estudos, as análises de configurações e arranjos do sistema elétrico, assim como seus parâmetros, a influência destes na configuração ou arranjo ótimo dos dispositivos de proteção, além do atendimento aos requisitos das normas aplicáveis. / The work presents a methodology regarding to low-voltage surge protective device coordination. This is based on adequacy of the isolation and immunity level of electrical and electronic equipment and the energy absorbed by the protective devices. The main motivation is related to the required nuclear plant reliability and safety criteria, in whose the surge protection coordination can assume an important role. An interactive methodology is carried out to optimize the analysis and the protection device specification, considering the adoption of analytical and numerical methods. Electrical and electronic equipment models, when submitted to voltage and current surges, in addition to surge protective devices, are implemented in the electromagnetic transient simulator - ATP. In these studies, the analysis of electrical system configurations and arrangements, as well as their parameters, and their influence on the configuration or optimum protective device arrangement, besides compliance with the requirements of applicable standards are highlighted.

The dokument was created with ZDT company cooperation and consists of two main parts. The first and also main part is handling construction and strength check issues of two-axis traktor trailer chassis Grand super. The second part contains design and strength check of rear protective device against small vehicle under passing. Strength check is performed in I-DEAS enviroment. The fixings are chassis frame assembly drawing, chassis frame welding assembly drawing and drawbar assembly drawing.

This study focused on designing a training programme for audiometricians, using the principles of instructional design. Instructional design is the continuing, systematic development of instructional specifications, utilizing researched strategies and principles to create detailed outcomes for the development, implementation, evaluation and maintenance of training programmes. An audiometrician is defined by SANS (10083:2004), as a person registered with the Health Professions Council of South Africa as an audiometrician, hearing aid acoustician or someone trained in audiometry. Audiometricians are adult learners. Therefore, in addition to instructional design principles, the principles of adult learning were also incorporated in the training programme. The successful training of audiometricians may ensure that noise induced hearing loss is significantly reduced when audiometric monitoring is appropriately implemented as part of a hearing conservation programme. Training for audiometricians is critical in this process as incorrect audiometric monitoring may negatively influence the outcomes of a hearing conservation programme. This study followed a descriptive research design where the results were described in a quantitative manner. Data was collected by means of electronically mailed questionnaires. All participants were practicing audiometricians at the time of the study and were registered with the South African Society for Occupational Health Nursing. All participants had an audiometric certificate as qualification. For the analysis of data, 181 completed questionnaires were used. The results were analyzed and described in terms of the respondents’ own experience regarding audiometry; their opinions regarding the topics they have been taught in audiometry; the duration of their own training programmes and their opinions regarding a future training programme for audiometricians. Based on the results of the above analysis, the instructional design programme for audiometricians was developed. The obtained results were used to determine what the topics, content, duration, learning outcomes and learner evaluation methods should be in the development of a training programme for audiometricians. This research study developed a training programme for audiometricians in order to ensure that all future audiometricians have the necessary knowledge to perform comprehensive hearing evaluations, interpret audiometric findings and thereby assist in reducing noise induced hearing loss in the industrial sector through hearing conservation programmes. AFRIKAANS : Hierdie studie is toegespits op die ontwerp van ‘n onderrigprogram vir oudiometriste waarin die beginsels van onderrigontwerp toegepas is. Onderrigontwerp behels die deurlopende en stelselmatige ontwikkeling van onderrigspesifikasies deur gebruik te maak van nagevorsde strategieë en beginsels om gedetailleerde uitkomste vir die ontwikkeing, evaluering en onderhoud van opleidingsprogramme daar te stel. ‘n Oudiometris word gedefinieer deur wetgewing (SANS 10083:2004) as ‘n person wat geregistreer is by die Health Professions Council of South Africa as ‘n oudiometris, gehoorapparaat akoestikus of iemand wat opgelei is in oudiometrie. Oudiometriste is volwasse leerders. Om hierdie rede is nie net die beginsels van onderrigontwerp nie, maar ook die beginsels van volwasse leer in die onderrigprogram geïnkorporeer. Suksesvolle onderrig van oudiometriste kan verseker dat die voorkoms van geraas-geïnduseerde gehoorverlies verminder, mits oudiometriese monitering toepaslik as deel van ‘n program vir gehoorkonservering geïntegreer word. Opleiding vir oudiometriste is krities belangrik in hierdie proses want indien oudiometriese monitering verkeerd gedoen word, kan dit die gehoorkonserveringsprogram in totaliteit negatief beïnvloed. ‘n Beskrywende navorsingsontwerp is in hierdie studie gebruik en die resultate is kwantitatief beskryf. Data is deur middel van vraelyste wat elektronies versend is, versamel. Al die deelnemers was ten tye van die studie praktiserende oudiometriste wat by die South African Society for Occupational Health Nursing geregistreer was. Elkeen was in besit van ‘n oudiometriese sertifikaat as kwalfikasie. Vir data-ontleding is 181 voltooide vraelyste gebruik. Die data was geanaliseer en beskryf in terme van die respondente se eie ervaring ten opsigte van oudiometrie; hul mening omtrent die temas wat by hul opleiding ingesluit was; die duur van hul opleidingsprogramme en hul idees omtrent ‘n toekomstige opleidingsprogram vir oudiometriste. Die onderrigontwerp-program is op grond van die resultate van bognoemde analise ontwikkel. Die resultate wat verkry is, is gebruik om die temas, inhoud, duur, leeruitkomste en evalueringsmetodes in die ontwikkeling van ‘n opleidingsprogram vir oudiometriste te bepaal. Hierdie studie is gerig op die ontwikkeling van ‘n opleidingsprogram vir oudiometriste met die doel om te verseker dat hulle oor die nodige kennis beskik om omvattende gehoorevaluerings uit te voer, om oudiometriese bevindinge te interpreteer en daardeur, in gesondheidssorgprogramme, by te dra tot die vermindering van geraas-geïnduseerde gehoorverlies in die industriële sektor Copyright / Dissertation (MCommunication Pathology)--University of Pretoria, 2012. / Speech-Language Pathology and Audiology / unrestricted