• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.2216-2217
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• 2008

This paper write about earth system for the prevention electric shock and a protection of equipment in england. The IEC60364 and BSI(British Standards Institution) define earthing method(IT, TT, TN-C, TN-S, TN-C-S)-BSI is british standards and in case of england almost use the TN system. TN system can classify TN-S & TN-C-S(PME). The findings on survey in england are used the TN-S system and TN-C-S system about 70% and residue 30% are used TT system and IT system from the exiting state of things.

• 조명전기설비학회논문지
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• 제24권1호
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• pp.56-62
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• 2010

본 논문에서는 IEC 60364에서 제시하고 있는 접지계통(TT접지계통, TN-S 접지계통 및 TN-C)의 누전차단기 동작특성 및 보호도체의 임피던스변화에 따른 Loop Impedance 특성분석을 실시하였다. 분석결과 Loop Impedance의 경우 저항성분과 인턱턴스성분에 영향을 받는 것으로 나타났다. 접지계통별 전류 전압특성은 TN-S 접지계통 및 TN-C 접지계통의 경우 사고전류가 높고 접촉전압이 낮은 특성을 나타낸 반면 TT 접지계통의 경우 사고전류는 낮고 접촉전압이 높게 나타남을 확인하였다.

• 조명전기설비학회논문지
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• 제21권8호
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• pp.113-120
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• 2007

본 논문은 TN-C-S계통에서 중성선 겸용 보호도체(PEN도체)의 단선고장시 감전의 위험성 및 보호대책에 관한 것으로 PEN도체의 단선고장시 노출도전성 부분의 접촉전압을 줄이기 위하여 전원측 접지저항과 수용가 추가접지 저항에 따른 PEN도체 단선시 노출도전성 부분에 나타나는 접촉전압을 실험적으로 조사하였다. 그 결과 TN-C-S 계통으로 공급되는 설비에 대하여 등전위본딩은 중요한 요건이다. 수용가의 인입구에 추가접지를 하는 것은 PEN 도체의 단선시 노출도전성 부분에 나타나는 접촉전압을 저감시키는 방법 중의 하나이다. 접촉전압을 안전전압 50[V]이하로 제한하는데 필요한 추가접지의 접지저항은 부하용량과 고장회로정수에 의하여 정해진다. 또한 부족전압계전기는 TN-C-S계통에서 PEN도체의 단선고장을 검출할 수 있는 적절한 해결방안이 될 수 있다.

• 조명전기설비학회논문지
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• 제26권5호
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• pp.58-64
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• 2012

In electric power supply systems, an earthing system determines the electric potential of the conductors related to that of the Earth's surface. The choice of earthing system has implications for the safety of the power supply systems. There are considerably different regulations for earthing (grounding) systems in each country. A protective earth(PE) conductor ensures that all exposed conductive surfaces are at the same electric potential as the earth surface. This paper deals with that when PEN conductor of TN-C-S system is disconnected, dangerous touch voltage causes personnel body to be harmed and human being's property to be damaged seriously. For this reason, this paper explains how serious problems can occur when the fault current flows. As a consequence, we can understand how we can design earthing system properly to ensure the personnel safety against earth faults. The result shows the way that TN-C-S system can be applied safely in Korea.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.59-62
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• 2009

In electrical power supply systems, an earthing system determines the electrical potential of the conductors relative to that of the Earth's conductive surface. The choice of earthing system has implications for the safety of the power supply. Note that regulations for earthing (grounding) systems vary considerably among different countries. A protective earth(PE) connection ensures that all exposed conductive surfaces are at the same electrical potential as the surface of the Earth, This paper investigates that when PEN conductor of TN-C-S system is disconnected, dangerous touch voltage is caused at personnel body. According to this paper, we can understand that when TN-C-S system is applied in Korea, what we should set up to ensure the personnel safety from fault current.

• 조명전기설비학회논문지
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• 제24권6호
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• pp.67-74
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• 2010

국내의 저압수용가 대부분은 한국전력공사의 TN-C접지방식으로부터 공급받고 있으나 부하설비는 TT 접지방식을 위주로 한 전기설비기술기준에 따라 시설되어 있다. 본 연구에서는 정보기술설비를 뇌서지로부터 보호할 수 있는 적절한 전원계통접지방식을 제안하기 위해서 TT, TN계통의 뇌서지에 대한 보호성능을 연구하였다. 그 결과, 뇌서지가 배전계통의 중성선에 입사한 때 TT계통의 기기접지단자와 전원선의 중성점 사이에 높은 전위차가 발생하였으며, 예민한 컴퓨터설비가 손상될 위험성이 있으므로 TT계통은 적합하지 않다. 뇌서지로부터 저압 설비를 보호하기 위해서는 등전위본딩이 중요한 요건이며, TN계통이 중성선을 통하여 입사하는 뇌서지의 저감에 가장 우수하였으며, 수용가 인입구에서의 추가접지도 바람직한 방법이다.

• 전기학회논문지
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• 제62권8호
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• pp.1163-1168
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• 2013

The maximum allowable value of loop impedance($Z_s$) to secure the operation of overcurrent protective devices and the safety for indirect contact is a very important in TN-C-S system. The loop impedance is divided into inner loop impedance which consumer can adjust and external loop impedance($Z_e$) which only electric operator can adjust. Thus, an external loop impedance which limits to less than a certain value is a very important factor for human body protection against electric shock in TN-C-S system. The concept of loop impedance($Z_s$) is recently introduced to the domestic, the study about external loop impedance is yet insufficient. However, the study about the reference impedance as specified by the IEC 60725 standard to improve the quality and reliability of the power supply is being made. In this paper, reference value of external loop impedance($Z_e$) to meet domestic environment will be proposed by the nationwide measurement and statistical analysis.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.497-499
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• 2003

Electro-optical (EO) performances of the ion beam aligned twisted nematic (TN)-liquid crystal display (LCD) with oblique ion beam exposure on the DLC thin film surface were studied. An excellent voltage-transmittance (VT) curve of the ion beam aligned TN-LCD was observed with oblique ion beam exposure on the DLC thin film surface for 1 min. Also, a faster response time for the ion beam aligned TN-LCD can be achieved with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved.

• 조명전기설비학회논문지
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• 제26권2호
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• pp.86-91
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• 2012

A conductor has been produced according to IEC standard and low voltage electrical facility has been installed according to IEC 60364. So we must comply with international standard for design, construction and inspection. But because of many related and varied standards, it is difficult to apply to design and inspect for electrical equipment. We researched the necessity of design guide which is detailed and systematization from survey. For detailed design guide, we suggest calculation method of protective conductor cross-sectional area at TN-S system according to BS 7671 regulation and KS C IEC 60364 standard.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.47-50
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• 2001

Presently the Korean grounding system uses TN system, multi-grounding method with TT independent grounding method. Nevertheless TN system can't exist with TT system in the technological terms. If they coexist, it causes ground-fault circuit not to operate, and brings about different electrical potential rise by customer system. It brings about serious problems for safety. This paper aims for improving method of grounding system based on the technical analysis on instances in foreign countries and Korea. Almost standards and construction manner were apt to be internationalized after WTO/TBT agreement was concluded. The internal grounding systems should meet the international criteria and reliability for safety, and be provided with technologically impeccable standards.