가속 열화 시험에 따른 저압용 차단기의 물리적 특성에 관한 연구

• Published in: 한국안전학회지 Vol. 37; no. 6; pp. 1 - 8
• Main Authors: 강신동, Sin Dong Kang, 김재호, Jae-ho Kim
• Format: Journal Article
• Language: Korean
• Published: 한국안전학회 31.12.2022
• Subjects: accelerated degradation test; arrhenius equation; circuit breaker deterioration; ELCB; MCCB; MCCB; circuit breaker deterioration; ELCB; accelerated degradation test; arrhenius equation
• ISSN: 1738-3803; 2383-9953

This study analyzed the characteristics of insulation resistance and operating time based on an accelerated degradation test of a low-voltage circuit breaker. The experimental sample used a molded case circuit breaker (MCCB) and an earth leakage circuit breaker (ELCB). After measuring the insulation resistance of the circuit breakers, the leakage current was affected by an external rather than an internal structure. Furthermore, the insulation resistance of the circuit breakers with accelerated degradation was measured using a Megger insulation tester. In the accelerated degradation test, aging times of five, ten, 15, and 20 years were applied according to a temperature derived using the Arrhenius equation. Circuit breakers with an equivalent life of ten, 15, and 20 years had increased insulation resistance compared to those with less degradation time. In particular, the circuit breaker with an equivalent life of ten years had the highest insulation resistance. Component analysis of the circuit breaker manufactured through an accelerated degradation test confirmed that the timing of the increase in insulation resistance and the time of additive loss were the same. Finally, after analyzing the operating time of the circuit breakers with degradation, it was confirmed that the MCCB did not change, but the ELCB breaker failed.