• 전기의세계
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• 제20권4호
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• pp.5-11
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• 1971

This is a study on the insulation methods of home appliances and wiring devices proper to the new electric distribution system, primary side is 22.9/13.2KV, 3 phase 4 wire multigrounding system and secondary side is 380/220V, 3 phase 4 wire common neutral system. 1800V is determined as the electrical insulation voltage of the functional insulation because the abnormal voltage rise of the neutral line is 1300V. In the case of the functional insulation faults, the following safety methods will be suggested to protect the accidental faults: (a) class I appliance (accessible metal part is earthed), (b) class II appliance (doublly insulated), (c) class III appliance (operates at low voltage source). The mechanisms of the wiring devices are not improved to guarantee for the harmful electric shock but also the electrical insulation voltage is rised to 2000V.

• 한국화재소방학회논문지
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• 제17권2호
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• pp.1-5
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• 2003

현재 고감도의 누전차단기(RCD)와 배선용차단기(WCCB)및 퓨즈(Fuse)설치를 통하여 누전·단락사고와 과전류 발생시 차단기능을 부여함으로써, 전기화재의 발생을 억제하고 있으나, 매우 미흡한 실정이다. 특히 소손사고와 접속·접촉불량사고 및 순간단락사고 발생시는 구조적으로 차단이 불가능할 것으로 사료되며, 이에 대한 연구가 필요하다. 따라서 본 논문에서는 상기의 상황에 기초해서 가장 일반적으로 사용되고 있는 열동형 누전차단기(단락보호, 과부하 겸용)의 동작원리와 시험항목 및 기준분석을 통하여 문제점을 제시하고자 한다. 또한 저압 배선선로의 소손사고와 접속·접촉불량사고 및 순간단락사고 발생시 전등(R)부하 및 전동기(R-L)부하에 따른 누전차단기의 동작특성을 실제 실험을 통하여 검토하고자 한다.

• 한국전기전자재료학회논문지
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• 제21권2호
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• pp.182-187
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• 2008

This paper dealt with the detection algorithm of series arcing, which is a cause of electric fires in low-voltage wiring systems. To find the distinguished electrical features of series arc, we simulated series arcing by the arc generator specified in UL1699. An electric heater, an inverter-controlled vacuum cleaner, and a phase-controlled incandescent lamp were used as loads to generate series arcing. A high-pass filter (HPF) with the low cut-off frequency of 3 kHz at -3 dB was fabricated and applied to separate the series arc signal from the AC voltage source. The experiment showed that the high frequency signal generates randomly during series arcing, and the phase-controlled incandescent lamp produces high frequency pulses even in normal state. In this case, the magnitude, the width, and the randomness of high frequency signal should be analyzed to estimate series arcing precisely.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.37-42
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• 2006

전선에서 전압강하는 열 손실을 의미한다. 이 열은 절연체의 특성을 변화시켜 절연성능을 저하시키게 되고 나아가 누전, 감전, 정전 및 화재 등의 사고를 일으키는 원인이 되기도 한다. 그러므로 전압강하에 대한 최적화 설계는 전기설비의 안전성과 경제성을 보장하는 중요한 요소가 되고 있다. 이에 저압의 전기설비인 가로등, 빌딩, 지하철역사 등 공공의 안전확보가 요구되는 다중 분산부하계통에서의 전압강하가 전기배선에 미치는 영향을 분석하고, 안전성 및 경제성 확보를 위한 전압강하산정 프로그램 및 최적화 방안을 연구 제시하고자 한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권11호
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• pp.498-502
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• 2005

The objectives of this paper are to provide information on the characteristics of the discharge signals in a low-voltage indoor outlet. Most of electrical fires are caused by short circuits, overheating of wires, deterioration and incomplete connection of wiring devices. The last two cases are predictable before the occurrence of fire because of its slow progress. We have simulated the discharge signals caused by the deterioration and incomplete connection of wiring devices using aged outlets. From the experimental data, we could characterize the frequency spectrums of the discharge signals depending on the cases. The higher frequency components of the signal are attenuated by the capacitance and inductance of power lines as the measuring point is getting away from the discharges. Main frequency components of the discharge signal are existent at 600kHz - 1.5MHz in incomplete connections and at 210H7z - 8MHz in deteriorations of the outlet.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 전기설비
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• pp.12-15
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• 2005

The subject of this research is not only to examine effects on electrical wiring that voltage drops make in low voltage load facilities found in apartments, buildings street lightings, factories, and etc, but also to discuss the voltage drops computation program on distributed random loads to optimize their safety and economy.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권6호
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• pp.270-275
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• 2005

In order for the application of the in-vivo endoscopic biopsy, a micromirror which can be driven at a low voltage is required. In this paper, a two-step micromirror composed of bottom electrodes, moving plate and top mirror plate is proposed. Because an electrical wiring of two plates are separated, they can be actuated separately. Therefore, an intermediate moving plate plays an important role in reducing the driving voltage in half. The designed device was fabricated by the surface micromachining. Maximum rotation angle of $6.3^{\circ}$ was obtained by applying DC 48V, while a conventional one-step mirror pulled down at DC 120V. The designed structure can be used in microphotonic applications requiring low driving voltage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.628-632
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• 2002

Low voltage circuit breakers which interrupt rapidly and raise the reliability of power supply are widly used in power distribution systems. In the paper, it was investigated how much Interrupting capability was improved by correcting the shape of the contact system in molded case circuit breaker(below MCCB), especially arc runner. Prior to the interrupting testing, it was necessary for the optimum design to analyze electromagnetic forces on the contact system, generated by current and flux density. This paper presents both our compuational analysis and test results on contact system in MCCB

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2004년도 하계학술논문발표회 논문집
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• pp.26-31
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• 2004

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2004년도 추계학술논문발표회 논문집
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• pp.287-291
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• 2004