Transformator daya merupakan peralatan kritis dalam sistem penyaluran tenaga listrik yang membutuhkan proteksi internal yang andal. Penelitian ini menganalisis kasus gangguan pada transformator daya 150/20kV 60MVA di Gardu Induk Kota Agung dan mengimplementasikan solusi berbasis Early Warning System Relay’s Transformator (EWARS). Latar belakang penelitian ini adalah terjadinya gangguan pada tanggal 10 Maret 2023 berupa trip LV Winding Temperature yang disebabkan oleh endapan karbon pada kontak limit switch relay mekanik. Meski sudah diterapkan pemeliharaan berkala condition based maintenance (CBM), masih terdapat celah dalam pemantauan kondisi relay mekanik secara real-time. EWARS diimplementasikan sebagai sistem pemantauan berkelanjutan yang mengukur tegangan DC untuk mendeteksi anomali peralatan. Metodologi penelitian meliputi implementasi EWARS dan pengukuran perbandingan kinerja menggunakan multimeter Fluke 87V series sebagai standar pembanding. EWARS dirancang untuk memantau kondisi transformator secara real-time dan berkelanjutan melalui pengukuran tegangan DC, yang dapat mengindikasikan anomali peralatan relay mekanik trafo. Hasil penelitian menunjukkan bahwa implementasi EWARS memberikan manfaat signifikan dalam aspek teknis melalui pemantauan real-time dan aspek finansial melalui efisiensi biaya kerugian gangguan pemadaman. Penelitian ini menghasilkan kontribusi praktis dalam pengembangan sistem pemantauan transformator daya yang lebih andal.

Power transformers are critical equipment in power distribution systems that require reliable internal protection. This research analyses the case of a fault in a 150/20kV 60MVA power transformer at Kota Agung Substation and implements an Early Warning System Relay's Transformer (EWARS) based solution. The background of this research is the occurrence of a disturbance on 10 March 2023 in the form of an LV Winding Temperature trip caused by carbon deposits on the mechanical relay limit switch contacts. Although condition-based maintenance (CBM) has been implemented, there is still a gap in monitoring the condition of mechanical relays in real-time. EWARS is implemented as a continuous monitoring system that measures DC voltage to detect equipment anomalies. The research methodology includes the implementation of EWARS and performance comparison measurement using Fluke 87V series multimeter as a standard comparison. EWARS is designed to monitor transformer conditions in real-time and continuously through DC voltage measurements, which can indicate transformer mechanical relay equipment anomalies. The results show that the implementation of EWARS provides significant benefits in technical aspects through real-time monitoring and financial aspects through cost efficiency of outage fault losses. This research resulted in practical contributions in the development of a more reliable power transformer monitoring system.