Short-circuit indicators detect short circuits, while earth fault indicators detect faults to earth. A combined fault passage indicator supports the location of both fault types and helps identify the affected section of the grid.

A fault passage indicator helps grid operators identify the affected grid section after a short circuit or earth fault. This reduces fault-search time and supports faster restoration of power supply in substations, secondary substations and distribution grids.

EOR-1DS is suitable for secondary substations when an economical indicator with simple operation and parameterisation without software is required. It supports Modbus RTU communication.

EOR-3DS is suitable when the application requires configuration with AEToolbox, extended SCADA and communication protocol support, cyber security functions or integration into digital secondary substations.

Available methods include the qu2 transient algorithm, directional short-circuit and earth fault detection, pulse location, the wattmetric cos(φ) method and the reactive power direction sin(φ) method. EOR-3DS additionally supports the qui method for restriking faults and the harmonics method.

Short-circuit and earth fault indicators are used in digital and conventional secondary substations, transformer stations at grid nodes, substations, transmission and distribution grids, and industrial plants and production facilities.

Communication depends on the selected device. EOR-1DS supports Modbus RTU. EOR-3DS supports Modbus RTU/TCP, IEC 60870-5-101/104, IEC 60870-5-103 including fault records, IEC 61850 GOOSE, DNP 3.0 and MQTT functions.

Device selection should consider the required fault location methods, voltage and current measurement concepts, communication interfaces and whether the device will be used in a conventional or digital substation.