정온전선의 화재 위험성에 관한 연구

• Published in: 한국안전학회지 Vol. 39; no. 3; pp. 7 - 13
• Main Authors: 이정현, Jung Hyun Lee, 김시현, Si Hyun Kim, 박예진, Ye Jin Park, 강신동, Sin Dong Kang, 김재호, Jae-ho Kim
• Format: Journal Article
• Language: Korean
• Published: 한국안전학회 30.06.2024
• Subjects: critical point; deterioration; fire risk; heating wire; ignition; PTC(Positive Temperature Coefficient); self-regulating heating cable; 안전공학; heating wire; critical point; self-regulating heating cable; PTC(Positive Temperature Coefficient); deterioration; ignition; fire risk
• ISSN: 1738-3803; 2383-9953

This study examines the physical characteristics of self-regulating heating cables caused by increased temperature and fire risk due to local degradation. A thermo hygrostat system, a convection dryer, a digital multimeter (Agilent 34465 A), NI DAQ, and the LabVIEW program were used to assess the physical properties in response to temperature fluctuations. As the temperature increases, the resistance of the self-regulating heating cable increases; however, when the critical point is exceeded, the resistance sharply decreases. A problem arises when the resistance value cannot return to its original state even though the temperature is lowered to the initial state. Moreover, when the ambient temperature rises while power is applied, the resistance value initially increases, and the flowing current decreases, maintaining a constant state. However, when the critical temperature is exceeded, the flowing current increases because of a rapid decrease in the resistance value, progressing to ignition. When the resistance value decreases because of the deterioration of one local area, the total resistance value becomes less than the initial resistance value. Therefore, the flowing current increases and an ignition problem occurs at one location where deterioration occurs. Despite the sustained flames and arcs resulting from the changes in the overall physical properties of the self-regulating heating cable and resistance variations due to local decline, the fire continued as the flowing current was lower than the operating current of the circuit breaker, failing to cut the power. In the case of self-regulating heating cables and heating wires, which are the leading causes of fires in winter, efforts are needed to ensure the need for periodic maintenance and the use of KS-certified products.