IED — Intelligent Electronic Device

What is IED?
IED — Intelligent Electronic Device
In the power sector, intelligent electronic devices (IED) are microprocessor based power system equipment, such as circuit breakers, transformers and capacitor banks, providing control and automation functions.
IEDs receive and process data from sensors and other equipment to issue control commands or adjust tap poisitions in order to prevent failures and maintain the desired voltage level.
- Common types of IEDs include protective relays, circuit breaker, capacitor bank switches, recloser controllers and voltage regulators.
- Most IEDs carry communication ports and standard communication protocol technology (e.g. DNP3, IEC 104 or IEC 61850) to communicate directly with SCADA systems or RTUs.
- The term is often also used as a synonym for modern protection relays, which use a microprocessor to perform several protective, control and related functions.
- Modern IEDs are also designed to support the IEC 61850 standard for substation automation, which provides full interoperability and enables advanced protection and communication functions.
- With increasing intelligence, IEDs are used as a new alternative to, or a complement to traditionally used remote terminal units (RTUs).

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Grid & Substation Automation
- RTU — Remote Terminal Unit
- SCADA — Supervisory Control and Data Acquisition
- IED — Intelligent Electronic Device
- SER — SEQUENCE OF EVENTS RECORDING
RTU most commonly stands for Remote Terminal Unit, but is sometimes also used as an abbreviation for Remote Telemetry Unit or Remote Telecontrol Unit.
RTUs are devices that rely on microprocessors and communication interfaces to automatically monitor and control field devices and establish a bridge to the plant control or SCADA (supervisory control and data acquisition) systems.
Supervisory control and data acquisition (SCADA) systems collect, monitor and process real-time data to:
- Automate and control industrial processes remotely or locally
- Provide a human-machine interface (HMI) to directly interact with devices such as relays, sensors, generators, pumps, valves and others
- Record events and automate reporting
An Intelligent Electronic Device (IED) is a term used in the electric power industry to describe microprocessor-based controllers of power system equipment, such as circuit breakers, transformers and capacitor banks.
Sequence of events recording (SER) is performed by microprocessor based systems, which monitor collected data inputs and record the time and sequences of the changes.
Sequence of events recorders rely on external time sources such as GPS or radio clocks to record the exact time of state of each change.
IEDs & iGrid
Our group partner Thytronic provides state-of-the-art IEDs with advanced communication capabilities.
Thanks to our numerous projects accross the world, we have a long track-record of IEDs we have integrated and worked with.

X‑MORE Family by Thytronic
Multi-function high-end IEDs for protecting, monitoring and controlling power systems
- Accurate measurements
- Modular hardware and software
- High-precision time synchronization
- iGrid substation automation software
for Feeders, Transformers, Capacitor Banks, Generators, Motors and many more

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