One approach to improve the reliability of the electricity distribution system is by optimizing the placement of reclosers. Reclosers should be placed at locations with the highest likelihood of frequent disruptions while considering the number of affected customers, as fewer affected customers result in lower SAIFI and SAIDI values will be. Optimization can be analyzed from both technical and geographical perspectives. This study employs PSS SINCAL 21.5, which which integrates of GIS (Geographic Information System) features, enabling both technical and geographical considerations to be made using a single software. This study was also conducted to improve reliability indices such as SAIFI and SAIDI, as well as to determine the results before and after recloser placement optimization. Based on the analysis of reliability index values for the Cemara feeder before optimization using the Section Technique Method, resulting in SAIFI of 4.57 times/customer/year, and SAIDI of 14.35 hours/customer/year. After optimizing recloser placement using several scenarios by relocating reclosers at placement points based on technical and geographical considerations using the PSS SINCAL 21.5 software, the most optimal recloser placement was found in Scenario 1, resulting in a SAIFI value of 3.87 times/customer/year and a SAIDI value of 13.26 hours/customer/year closest to SPLN 68-2:1986. The reduction in both indices demonstrates that with proper recloser
placement, outages can be isolated more quickly, and the impact on customers can be minimized. This study serves as the basis for technical planning in the development of a reliable distribution system, particularly for reliability enchancement of the Cemara Feeder.