Thursday, June 21, 2018

RTUs and IEDs - Essential Components of a SCADA System


With almost four decades of experience as an electrical distribution and transmission high-voltage engineer, Dianoush Emami has enhanced the efficiency and performance of high-voltage electrical transmission equipment, components, and systems. During his career, Dianoush Emami created four task forces, one of which addressed remote terminal unit (RTU) and intelligent electronic device (IED) data exchange. 

Supervisory control and data acquisition (SCADA) systems collect data and control large-scale systems by monitoring network functions at the supervisory level. They can regulate a process, or control machinery. RTUs and IEDs are two components of a SCADA system that perform monitoring and controlling functions. 

An RTU is most often used in industrial environments for remote monitoring and control of automated devices and systems. A self-contained computer, an RTU has a processor, memory, and storage. It is intelligent enough to control multiple processes without user intervention or a master controller. This allows an RTU to send telemetry data to distributed control systems (DCS) and SCADA systems. RTUs monitor equipment within the SCADA system, including IEDs.

An IED creates communication between remote sensors and controllers and a communications network. It can control many parts of a piece of equipment so the equipment works in accord with the rest of a system. It also gathers information from power equipment within the SCADA system. For example, if an IED senses a certain level, such as voltage, is too high or low, it can initiate a control function to correct the level back within normal limits.