@thesis{thesis,
		author={Sampurno  Sampurno and SARASWATI  ANJANI},
		title ={KAJIAN KOORDINASI PROTEKSI TRANSFORMATOR-3 150/20 kV; 60 MVA DI GARDU INDUK CAWANG LAMA},
		year={2018},
		url={http://156.67.221.169/810/},
		abstract={Power transformer is an electrical device which function is to distribute electrical power and changes the value of its voltages. Therefore, transformer have an important role in the power system and needs to have reliability when it operates. This is attainable by installing protection tools to avoid the internal and external interferences. Protection system protects electrical equipments from the disturbances so that the equipments will not be damaged, also to minimize the blackout times and areas. One of transformer protection apparatus is protection relay. On 60 MVA transformer-3 150/20 kV Cawang Lama Substation is protected with five kind of relay, which are, differential relay, restricted earth fault relay, over-current relay, ground fault relay, and SBEF relay. On both side (HV and LV) of transformer, the setting of differential relay and restricted earth fault relay are already suitable with SPLN, which the minimum setting value is 30%. On 20 kV side of transformer, over-current relay has pick-up current and tms value are 1,04A and 0,072. While for ground fault relay are 0,173205 A and 0,132. Also for SBEF relay are 1,7332 A and 0,75. On 150 kV side of transformer, over-current relay has pick-up current and tms value are 0,924 A and 0,168. And for ground fault relay are 0,15936 A and 0,31.}
		}