ANALISIS HASIL UJI PEMUTUS TENAGA (PMT) TRANSMISSION LINE MANDIRANCAN-PEMALANG #3 GITET 500KV MANDIRANCAN TERHADAP KEANDALAN PENYALURAN TENAGA LISTRIK

Abstract

Electric power transmission is the process of delivering electrical energy from generation to consumers through interconnected substations (GIs). In this system, various essential equipment are used, including Circuit Breakers (CBs), which function to interrupt electric current under load conditions. On the 500 kV Mandirancan–Pemalang#3 EHV Substation line, two CBs are used, namely 7B5 and 7AB5. These CBs undergo maintenance every two years with tests such as insulation resistance, contact resistance, contact synchronization, SF6 gas, visual inspection, and thermovision. The test results showed good values: insulation resistance >500 MΩ, contact resistance <960 µΩ, synchronization <10 ms, gas pressure >6 bar, purity 99.99%, dew point -46°C, and temperature <50°C. Although there were indications of functional decline, the equipment still met the applicable standards. During a lightning disturbance, the CBs proved reliable with a fast reclose capability (<90 ms), ensuring the continuity of power transmission remained secure.