Abstract

This study performed the quantitative distribution analysis of created voids to an insulator when applying general flame and DC short-circuit current to 2.5 $mm^2$ HIV (600 V Grade Heat-Resistant Polyvinyl Chloride Insulated Wires). The diameter of cross-section of HIV normal product and the radius of conductor were measured to be 3.3 mm and 1.8 mm. The exterior of HIV exposed to general flame showed severe carbonization and its interior exhibited voids created by dechlorination reaction. This study observed the characteristics that, when the shortcircuit current applied for 2 seconds from a DC 12 V lead battery, the conductor and neighboring insulator were melted, causing the insulator adhering to the conductor. On average, 87 voids were created on 10 mm of the HIV. The average diameter of voids was 0.25 mm. In addition, it was found that, when the short-circuit current applied for 4 seconds, the interior of insulator in contact with conductor severely carbonized and showed exfoliation phenomenon. On average, 47 voids were created, with more voids at the bottom. The average diameter of voids was 0.20 mm. When the short-circuit current for 6 seconds, most parts of upper part of conductor was carbonized, 20 voids were created. The average diameter of voids was measured to be 0.24 mm. It could be seen that the created voids received little influence by the type of energy source and the number of created voids was reduced as the energy supply time increased.

Keywords

• quantitative distribution;
• general flame;
• DC short-circuit current;
• HIV;
• dechlorination reaction

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References

1. C. S. Choi et al, "Introduction to Electrical Circuit", Honghwa Technology Publishing Co., pp. 12-18, 138-139, 2012.
2. C. S. Choi et al, "Firefighting and Electrical Installation", Honghwa Technology Publishing Co., pp. 137,148, 2012.
3. K. Y. Song, "Transmission and Distribution System", pp. 30, 524, Dongilbooks, 2008.
4. Robert L. Boylestad, "Introductory Circuit Analysis", Macmillan Publishing Co., pp. 39-51, 2005.
5. M. H. Sunwoo et al, "Automotive Mechanics", pp. 245-249, Intervision Publishing Co., 2004.
6. C. S. Choi, H. W. Kim, K. S. Lee, Y. S. Lim, C. H. Lee, and J. H. Chung, "Electrical Fire Engineering", Honghwa Technology Publishing Co., pp. 15-19, 189-224, 2004.
7. S. S. Kim and C. S. Choi, "A Study on the Quantitative Assessment of HIV Insulation Void Created by Electric Short of DC 12 V", Fall Annual Conference, Journal of the Korean Society of Safety, p. 48, 2012.
8. C. S Choi and H. K Kim, "Variation of Carbonization Pattern and Crystal Structure of Polyvinyl Chloride Wire Under the Thermal Stresses", The Transactions of The Korean Institute of Electrical Engineers, Vol. 57P, No. 3, pp. 332-337, 2008.
9. C. S Choi, "The Properties Analysis of 600 V Grade Polyvinyl Chloride Insulated Wire with Variation of Thermal Stress", Korean of Institute of Fire Science & Engineering, Vol. 15, No. 1, pp. 108-115, 2001.
10. C. S. Choi, H. K. Kim, and D. O. Kim, "A Study on the Characteristics Analysis of Strands Melted by Over Current", Journal of the Korean Society of Safety, Vol. 19, No. 1, pp. 60-65, 2004.
11. C. S Choi, H. K Kim, and K. M Shong, "A Study on the Short-Circuit Characteristics of Vinyl Cords Damaged by External Flame", Korean of Institute of Fire Science & Engineering, Vol. 18, No. 4, pp. 72-77, 2004.
12. C. S. Choi, K. S. Lee, and D. C. Lee, "Analysis of Compositive Variation with Thermal Deterioration for 600 V Grade Heat-Resistant Polyvinyl Chloride Insulated Wires", The Transactions of The Korean Institute of Electrical Engineers, Vol. 49C, No. 1, pp. 8-12, 2000.
13. W. V. Titow, "PVC technology", Elsevier Applied Science Publishers, p. 857,1186, 1191,1194, 2011.