• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.235-235
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• 2009

This paper is that study transformation and insulating performance decrease of HIV wire which is using at general electricity structure or home interior wiring of less than AC 600V by over current. When current raised 1A at 1sec, HIV wire insulator is partial charred with white smoke at 86A and conductor of HIV wire is exposed at 90A. When keep time for 5 minutes, insulating performance of the HIV wire decreased rapidly at 45A.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.1
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• pp.8-12
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• 2000

The properties variation by deterioration of the 600V grade heat-resistant polyvinyl chloride insulated wire(HIV) was analyzed. The weight variation of the thermal deteriorated HIV was about 42% at 80$0^{\circ}C$ and over. From the analysis result of the metallurgical microscope photographs it shows that the sorface of normal wire showed the elongated structures. However the elongated structures did not appear at $900^{\circ} and over and we could observe that particles were grown. The grown oxidized substances in the thermally deteriorated electric wire were observed by SEM. The CuL, CuK, $CuK_b$, OK and CIK spectra of the thermally deteriorated HIV at $300^{\circ}C$ were uniform regardless of the scanning length, but the spectra of CIK could not found at above $700^{\circ}. At the DTA analysis, the endothermic reactions were occurred around $3006{\circ}C\; and\; 400^{\circ}C$ and the exothermic reactions were occurred around $470^{\circ}, respectively.

• Fire Science and Engineering
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• v.33 no.2
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• pp.114-123
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• 2019

The paper relates to a study on the changes in performance of insulation sheath resulting from accelerated degradation of IV and HIV insulated wire. To assume insulation degradation of IV and HIV insulated wire, accelerated life tests using Arrhenius equation were conducted among accelerated life test models, and experimental samples of 0 year, 10 years, 20 years, 30 years, and 40 years in equivalent life were produced. Whereas the maximum tensile load were increased as accelerated degradation of IV and HIV insulated wire progressed, elongation percentage, rupture time, and flexibility of insulated wires were found to be gradually reduced. According to the additional surface analysis results for the insulated wires per equivalent life using a scanning electron microscope, mechanical properties of the insulator were observed to be reduced as insulation degradation resulting from aging progressed since phenomena such as formation of crystalline structures and perforation, etc. occurred on the sample surface with progression of accelerated degradation. Consequently, institutional replacement of insulated wires and preparation of repair times considering performance degradation of the insulator installed inside buildings are considered necessary in order to prevent in advance the risks of electrical fire resulting from degradation in insulation performance.

• Journal of the Korean Society of Safety
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• v.34 no.1
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• pp.8-13
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• 2019

Weight and elongation changes of IV and HIV insulations were measured simultaneously at several given temperature of $80^{\circ}C$, $90^{\circ}C$ and $100^{\circ}C$. And the lifetime was predicted using the Arrhenius model. Based on the initial weight values, a 50% elongation reduction was seen at 6.96% for the IV insulation and 10.29% for the HIV insulation. The activation energy from the slope of the lifetime regression equation was calculated as 92.895 kJ/mol(0.9632 eV) for the IV insulation and 95.213 kJ/mol(0.9873 eV) for the HIV insulation. Also, the expected lifetime at the operating temperature of $30^{\circ}C$ to $90^{\circ}C$ is 2.02 to 94.32 years, and longer lifetime was predicted on HIV insulated wires than on IV insulated wires. As a result, it was found that the thermal characteristics of the HIV insulated wires were about 12.44% better than those of IV insulated wires under the same conditions of use.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1401-1403
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• 1998

The composition, weight decrease, DTA, and surface structure of vinyl insulated wire with thermal treatment conditions have been investigated. The composition of Cu by EDX analysis indicates Cu, Cl, and O lines, and oxidation reaction results from thermal treatment. Thermal treated IV and HIV appeared chemical reaction at $269^{\circ}C$ and $265^{\circ}C$, respectively. SEM of thermal treated Cu at $250^{\circ}C$ disappears an elongation structure, and appears an original structure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.268-275
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• 2008

In this paper, we introduce a new method for detecting and estimating faults on a power line using the time-frequency domain reflectometry system. The system rests upon time-frequency signal analysis and uses a chirp signal which is multiplied by Gaussian envelope. The chirp signal is used as a reference signal, and we can get the reflected signal from a fault on a wire. To detect and estimate faults, we analyze the reflected signal by Wigner time-frequency distribution function and normalized time-frequency cross correlation function. In this paper we design an optimal reference signal for power line and implement a system for estimating fault distance on a power line with the TFDR implemented by PXI equipments. This approach is verified by some experiments with HIV 2.25mm power lines.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.8
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• pp.1184-1191
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• 2013

Probability of ignition due to arc-fault and energy of the arc-fault for the case of applying serial arc-fault interruption time of 120 V defined in UL 1699 to the voltage of 220 V of domestic condition and also for the case of applying it to the HIV wire type are analyzed. It has been confirmed that when the arc-fault occurs under 5 A, 10 A, and 20 A. Probability of ignition for the three different current conditions is 0.74(74%), 0.48(48%), and 0.32(32%) respectively for respective interruption time within 1 sec, 0.4 sec, and 0.2 sec. We discover that when we apply the same arc interruption time for 120 V defined in UL 1699 to the domestic environment of 220 V. The probability of ignition increases from 1.5% for 120 V condition to as much as 74% for 220 V condition. Conclusively, if we apply the standard for the serial arc-fault interruption time defined in UL 1699 for 120 V to the domestic condition of 220 V, the fire prevention effect of electric fire due to arc-fault equal to that of UL standard of 120 V can not be achieved.