• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.5
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• pp.90-98
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• 2007

The objective of this investigation was to reveal the cause of the faulted cable(LV URD(low voltage underground) cable). For the analysis, various types or equipments such as external pattern, thermal pattern, surface structure, thermal analysis, and property distribution were deployed. The international standards and the specification provided by the manufacturer of faulted cable were examined whether it fit the standards. The summary is as follows. (1) Discovered as a factor lowering insulation performance of the faulted cable: minimum thickness of the insulation layer specified by IEC 60502-1 and IEC 60811-1-1 was not fit. (2) Infrared absorption peaks measured by FT-IR spectrometer revealed that the measurements made for the same material did not conform and it is an important basis for proving heterogeneous composition of the insulation material. (3) It was found that PVC bedding was thermally fragile and therefore long term exposure at the site could cause similar fault pattern.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.54-60
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• 2008

It is impossible to database(DB) the patterns of power cable events and cause analysis of faulted cable because the product liability(PL) law have been enforced in Korea, since 2002. In additions, simulation and pattern of power cable events are needed for DB system under accelerated deterioration. In this paper, we tested for resistance to cracking of cable below the 22.9[kV] class due to thermal stresses. This method of exam is following IEC 60811-3-1(Common test methods for insulating and sheathing materials of electric cables). From the results, The 22.9[kV] class A power cable was discolored on the surface and significantly reduced in the longitudinal direction. As the thermal weight properties of A power cable was definitely varied, we are able to guess the problem of manufacture. If the cable was defect by the manufacture, the victims would be able to claim for damage in the PL system.

• Fire Science and Engineering
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• v.34 no.3
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• pp.8-17
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• 2020

In this study, the characteristics of HFIX insulated wire sheaths contaminated by pollutants were examined. KS C IEC 60811-1-3 standard was followed in performing the water-resistance wire tests. Pollutants were selected, and the specimens were exposed to the pollutants for a maximum duration of four weeks. The maximum tensile load and the elongation rate were measured each week. As the period of pollution exposure increased, the maximum tensile load of the specimens decreased by 6.22% and 6.52% at room temperature and high temperature, respectively, and 19.94% for specimens coated with a rust-proof lubricant. The elongation rate also decreased rapidly, such that the reductions in the properties of the sheath were significant. From the analysis of the surfaces using a scanning microscope, as the contamination period increased, structural changes such as perforation, split, and melting occurred, and the mechanical properties of the specimens decreased. Therefore, it is necessary to develop and follow an inspection cycle and periodically carry out repairs to prevent the deterioration of insulated wires.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.349-352
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• 2007

It is impossible to database(DB) the patterns of cable events and cause analysis of faulted cable because the product liability(PL) law have been enforced in Korea, since 2002. In additions, simulation and pattern of cable events are needed for DB system under accelerated deterioration. In this paper, we tested for resistance to nicking of cable below the 22.9kV class due to thermal stresses. This method of exam is following IEC 60811-3-1(Common test methods for insulating and sheathing materials of electric cables). First of all, set the cable in the thermal stress instrument, temperature changed from -20 degree to 120 degree. After thermal stress, we observed a surface crack of cable through microscope and carried out AC withstand voltage test.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.1
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• pp.82-87
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• 2008

It is impossible to database(DB) the patterns of power cable events and cause analysis of faulted cable because the product liability(PL) law have been enforced in Korea, since 2002. In additions, simulation and pattern of power cable events are needed for DB system under accelerated deterioration. In this paper, we tested for resistance to cracking of cable below the 22.9kV class due to thermal stresses. This method of exam is following IEC 60811-3-1(Common test methods for insulating and sheathing materials of electric cables). From the results, The 22.9kV calss A power cable was discolored on the surface and significantly reduced in the longitudinal direction. As the thermal weight properties of A power cable was definitely varied, we are able to guess the problem of manufacture. If the cable was defect by the manufacture, the victims would be able to claim for damage in the PL system.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.25-31
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• 2016

This paper has analyzed the structure, applicable regulations and the resistance characteristics of insulation ring type of CSST (Corrugated Stainless Steel Tubing for Gas). With the flammability test conducted in accordance with KS C IEC 60811-1-1, the evaluation of insulation resistance, temperature characteristics, and reliability has been conducted. An insulation ring type CSST consists of protective coating, tube, nut, insulation ring, packing, socket, and ball valve. Connecting an insulation ring type CSST to gas tubings for gas appliance is not permitted, moreover, the product shall be installed inside a sleeve pipe in case of buried installation such as the ceiling. Damages on protective coating and tube were detected when fire was applied to the test sample with a portable torch for 60 seconds. The insulation resistance of a normal product was $49.59M{\Omega}$, while that of the product completed the flammability test reduced to $9.21M{\Omega}$. The mean insulation resistance within the confidence Interval of 95% using the mini tap program 17 was $49.59M{\Omega}$ and the mean insulation resistance within the confidence interval reduced to $9.21M{\Omega}$. In the normal distribution analysis of 95% confidence interval, the value-P of the normal product was stable at 0.075 and AD(Anderson-Darling) statistic value was turned out to be 0.063, which is very normal, and the standard deviation was analyzed as 0.2586. The value P of the product completed the flammability test resulted in 0.005, the AD was 1.355 and the standard deviation reduced to 0.07908.