Short-Circuit and Earth Fault Indicators
Solutions for Varying Network Topologies
Short-circuit and earth fault indicators are used to detect and locate faults in medium-voltage grids, substations and secondary substations more quickly. Different applications require different fault location methods, communication options and levels of flexibility. This page helps users compare EOR-1DS and EOR-3DS and identify the right solution for conventional or digital substations.
Fit for the Intelligent Substations of Tomorrow
Products
Application Areas
EORSys - Short-Circuit and Earth Fault Detection
Our Short-Circuit and Earth Fault Indicators as an Essential Building-Block
In Substations & Secondary Substations
Our short-circuit and earth fault indicators make it possible to combine the advantages of different location methods. This makes it possible for the first time to prioritise and weight the methods in order to perfectly match them to the respective application.
This combination makes our devices particularly well-suited for use in both digital and conventional secondary substations. Naturally, these advantages also apply directly at the primary substation level.
Quick Comparison: EOR-1DS vs. EOR-3DS
Find the Right short-circuit and earth fault indicator for Your Application.
EOR-1DS
The economical indicator for
the secondary substation
EOR-3DS
The fault indicator for
the digital secondary substation
qu2 transient algorithm
Transient earth fault methodDirectional short-circuit and earth fault detection
Pulse location
Wattmetric method cos(φ)
Reactive power direction sin(φ)
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Simple operation and parameterisation without software
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Extensive cyber security features✔️
Flash memory up to 32 GBCapacitive in parallel with VDS systems, low power sensors (two-wire technology) and classic transducers
Rogowski folding transducers, low power sensors (two-wire technology) and classic transducers
Modbus RTU
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qu2 transient algorithm
Transient earth fault methodDirectional short-circuit and earth fault detection
Pulse location
Wattmetric method cos(φ)
Reactive power direction sin(φ)
qui-Method
Restriking faultsHarmonics method
Open setup as required with »AEToolbox« software
Certificate handling, user/role concept and encrypted connections
Extensive cyber security features✔️
Flash memory up to 32 GBCapacitive in parallel with VDS systems, Low power sensors (two-wire technology or RJ45) and classic transducers
Low power sensors (two-wire technology or RJ45) and classic transducers
Modbus RTU/TCP (Incl. "Modbus Master")
IEC 60870-5-101 / 104, IEC 60870-5-103 Including Fault Records, IEC 61850 GOOSE, DNP 3.0
MQTT Management&Operations
MQTT IoT
Patch- and Devicemanagement via MQTT
Mass remote parameterisation and firmware updatesvia MQTT Management&Operations-function
FAQ
What is the difference between short-circuit and earth fault indicators?
Short-circuit indicators detect faults involving high fault currents between conductors or to earth. Earth fault indicators are designed to detect single-phase faults to earth and support more targeted fault location in the grid.
Why are short-circuit and earth fault indicators important in medium-voltage grids?
They help utilities and grid operators detect faults faster, reduce search times and improve service restoration in substations, secondary substations and distribution networks.
When is EOR-1DS the right choice?
EOR-1DS is a strong choice when a cost-efficient fault indicator is needed for standard applications in secondary substations and when communication requirements are more limited.
When is EOR-3DS the better solution?
EOR-3DS is the better fit when the application requires advanced communication, flexible parameterisation and integration into digital secondary substations.
Which fault location methods can be relevant?
Depending on the grid and application, relevant methods can include transient earth fault methods, pulse location, directional methods, wattmetric methods or reactive power direction methods. The right combination depends on network conditions and the measurement concept.
Which applications are typical for these solutions?
Typical applications include digital and conventional secondary substations, transformer stations at grid nodes, substations, transmission and distribution grids, as well as industrial plants.
Why does communication matter for fault indicators?
In digital substations, communication interfaces and protocol support are essential for integration into SCADA and grid digitalisation strategies. Advanced devices can support broader interoperability and remote management functions.
Why does grid topology influence device selection?
Because the suitable fault location method, sensor concept and communication setup depend on whether the solution is used in a conventional or digital substation environment.
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