Fault detection and MV switchgear automation: Overcurrent fault detection is a key point for the MV grid control. The ability to detect these faults allows the operator of the Control Center to isolate the affected area very quickly. The direct measurement of the CT (Current Transformer) allows the user to know, in real time, the RMS current that flows through each line, as well as the current flowing in the neutral line. This value is compared with the threshold current and the time curves (IDTF) predefined by the user in order to determine if there is a fault state. The use of VPIS (Voltage Presence Indicating Systems) sensors when the overcurrent is detected, allows the user to know when the primary switchgear is opened. iRTU F family is the ideal solution for Control and Automation of existing MV Substations, allowing the detection of any kind of overcurrent that appears in their lines and reporting to the control center the kind of event that has been detected. With the overcurrent information and the voltage presence detection, the iRTU decides if there is a fault in the MV grid and whether the switchgear must be opened or not, when there is no voltage due to the opening of the HV substation feeder. For more information, visit us on: www.igrid-td.com