PENGUKURAN PENTANAHAN TRANSFORMATOR PADA GARDU DISTRIBUSI DI PENYULANG TARAKAN PT. PLN (PERSERO) RAYON SUKARAMI

Grounding system has function to protect equipment from over voltage and leakage current in the equipment. The purpose of this study is to determine the value of grounding transformers in substation distribution Tarakan feeder. To be considered the grounding system is the earth soil resistivity and electrodes used. To get a distribution substation earthing resistance value, we use direct measurement by using Digital Earth Tester without disconnect the grounding and manual calculation metode. From the results of direct measurements can be obtained grounding resistance value that varies from 0,72 Ω to 19,24 Ω while from the manual calculation metode the grounding resistance value are 35,78 Ω. From the direct measurement result there are some distribution substations that have value more than the standard value allowed by the Standard of Electrical Installation General Requirements (PUIL), which is ≤5 Ω. Therefore to keep the earth resistance value constant, there should be inspection routinely or periodical in every grounding system of distribution substations at Tarakan feeder