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	Anna Podobreeva Faculty: Electrotechnical Speciality: Electrotechnical Systems of Electrical Consumption Theme of Master's Work: «Working out of increase of networks 380-220V inhabited apartments fire safety recommendations» Scientific Supervisor: Alexander Kovalev

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Abstract Master's Qualification Work «Working out of increase of networks 380-220V inhabited apartments fire safety recommendations» Urgency        In networks 380-220 V of inhabited sectors use various kinds of loads, from low-power loads to big load. At work of these devices there can be emergencies, such as: short circuit, a sparking of the weakened contact connections. These kinds of failures may lead to damage of the expensive equipment, and in the worst cases – to a fire!        Devices of the protective disconnecting, which react with a differential current, they possess the complex of protective functions and in this sense they does not have analogues.        Residual - current device provide high degree of protection of people from defeat by an electric current at a direct and indirect touch, besides residual - current device provides decrease in fire danger of electroinstallations. It is necessary to notice that in case of a deliberate touch to current carrying parts application residual - current device is unique possible way of maintenance of protection, as well as in default protection principal views. They have possibility of the simple control of correct functioning of the device and for nonprofessionals by means of button "TEST" or in new workings out of firm Felten&Guilleaume of button "SERVICE". The work purpose        I need to develop recommendations which will allow to raise reliability and a fire stability of inhabited networks sector by expansion of possibility of existing protection means. Scientific value of work         Scientific value of work consists in development of protection means of networks by voltage 380-220 V of inhabited sectors, namely: increase of reliability Residual - current device and expansion of their functionality. Practical value of work        Practical value consists in working out of basic schemes and algorithms of protection work . Application of developed protection instead of existing protection means will allow to raise reliability of the given class of inhabited networks sector. Condition of a question        Operation of all kinds of electroinstallations represents certain danger to people. It causes of strict observance of safety requirements precautions regulations and corresponding qualification of the personnel serving these devices.        The body of the person possesses certain electric resistance which changes largely (from 500 to 100000 Ohm) and depends on many reasons: the general state of health, a thickness and a condition of an integument and its humidity, conditions of environment, duration of passage of a current and some other factors. In calculations under safety precautions resistance of a human body usually is accepted an equal 1000 Ohm.        To the person it is dangerous both variable, and the direct current, however the greatest danger are represented by an alternating current of industrial frequency (50 Hz). With increase of frequency of an alternating current danger of defeat decreases. Results of researches        There are two cases of a touch of the person to current carrying parts: bipolar when the person has concerned to two not isolated wires of an electric network, and unipolar when the person concerns one of wires.        More dangerous touch is bipolar, especially if the person has touched with two hands to a different wires (fig. 1). Thus the current passing through a body of the person, Ih in a three-phase four-wire network can reach value:        At a touch to two phases (a case 1) (1)        And at a touch to a phase and zero wires (a case 2) (2)        where Ul and Uf – accordingly linear and phase voltage of a network, V; Rh – resistance of a human body, the Ohm. The circuit 380/220 V Figure 1 - A touch of the person to wires of a three-phase four-wire network: to two phase wires (1) and to a phase and zero wires (2). (Animation: volume - 55 kB; size - 627 x of 512 pixels; amount of shots - 7; delay between shots - 100 ms; delay between the last and first shot - 200 ms; amount of cycles of reiteration - 15)        At a unipolar touch the person concerns to one of not isolated conductors of an electric part, or to not current carrying metal part of the electric equipment which have appeared energised as a result of damage of isolation. In this case value of the current passing through the person, depends not only on the enclosed pressure, but also from a mode of a neutral of the power supply, active resistance of isolation and capacity of wires in relation to the earth [14]. Conclusions        There is a basic scheme “The touch of the person to wires of a three-phase four-wire network” (fig. 1) in this work.        Weight of an electrical accident depends on value of a current and duration of its passage. It is considered that in most cases the current 0,1 A represents danger of death to the person. At this current which is passing from hand to a hand or from hand to feet during 3 with, there can come a heart paralysis. References        1. Ковалев А.П., Журавель Е.А., Товстик Ю.В. Статья О нормировании риска поражения человека электрическим током при эксплуатации установок. Уголь Украины, февраль - март 2002г. с.60-61.        2. Долин П. А. Основы техники безопасности в электроустановках: Учеб. Пособие для ВУЗов. – 2-е изд., перероб. И доп.- М.: Энергоатомиздат, 1984. – 448 с., ил.        3. Князевский Б.А. Охрана труда в электрорустановках: Учеб. Для вузов /Б.А. Князевский, Т.П. Марусова, Н.А. Чекалин; Под ред. Б.А. Князевского. – М.: Энергоатомиздат, 1983.-363с.        4. Правила устройства электроустановок. Раздел 1. Общие правила. Глава 1.1, 1.2, 1.7, 1.9. Раздел 1. Электрооборудование специальных установок. Главы 7.5, 7.6, 7.10 – 7-е изд.-М.: Издательство НЦ 7НАС, 2002-184с.        5. Шипунов Н.В. Защитное отключение. - Москва; "Энергия", 1968.        6. Харечко В.Н., Харечко Ю.Н. Устройства защитного отключения. - М.; МИЭЭ, 2002.        7. Шалыгин А.А. Рекомендации по применению устройств защитного отключения. - Светотехника, 2000, N6.        8. УЗО - устройства защитного отключения. Учебно-справочное пособие. - Москва; ЗАО "Энергосервис", 2003.        9. Кузилин А.В., Фотий А.Н., Якобс А.И. Об области применения электронных и электромеханических устройств защитного отключения в электроустановках жилых и общественных зданий России. - Промышленная энергетика, 1997, N 9.        10. Карякин Р.Н. Нормативные основы устройства электроустановок. - Москва; ЗАО "Энергосервис", 1998        11. Ф. Штепан. Устройства защитного отключения, управляемые дифференциальным током. - Прага; 2001.        12. Грунский Г.И., Шварц Г.К. Функциональное исполнение устройств защитного отключения и электробезопасность зданий. - Вестник Госэнергонадзора, 2000, N1        13. Электронная статья Устройства защитного отключения - что это такое? http://220v.info/texpod/t_uzo.html        14. Электроснабжение. Общие положения.  http://www.itsgroup.ru/document/proekt.htm        15. Электронный справочник Правила устройства электроустановок.  http://www.rza.org.ua/pue/a-35.html        At writing of this dissertation master's work is not yet completed. Final completion: December, 2009. Complete text of work and materials on the topic can be got author or his supervisor of studies after the specified date.

Autobiography