PENGARUH BEBAN LEBIH (OVER LOAD) TERHADAP NEW HIGH-SPEED FUSE (NH FUSE) PADA GARDU DISTRIBUSI DI PT. PLN (Persero) UNIT LAYANAN PELANGGAN (ULP) KUPANG

Abstract

This study aims to analyze the effect of overload on the performance of New High-Speed Fuse (NH Fuse) at distribution substations operated by PT PLN (Persero) Customer Service Unit (ULP) Kupang. Overload occurs when the electrical current exceeds the nominal capacity of distribution equipment, which leads to temperature rise, phase imbalance, and high neutral current. These conditions may accelerate NH fuse deterioration, cause faster fuse trips, and reduce the reliability of the distribution system. A quantitative method was employed, involving direct measurement of load currents on phases R, S, T, and N, followed by regression analysis to determine the magnitude of the overload effect on NH fuse performance. The results show that overload has a significant impact on NH fuse operation. Higher currents exceeding the fuse rating accelerate heating of the fusible element, causing the fuse to trip more quickly. Phase imbalance was also identified as a major factor contributing to high neutral current and early fuse damage. The study concludes that overload is directly proportional to the risk of HN fuse failure and tripping in distribution substations proper load balancing between phase and selecting fuse ratings that match the transformer load capacity are assential to maintain sysstem reliability within the ULP Kupang service area.