Which component is least likely to be an IED in an IEC 61850 environment?

In an IEC 61850 environment, the component that is least likely to be an Intelligent Electronic Device (IED) is a motor starter. IEDs are typically defined as devices that contain processing capabilities, are capable of communicating within a digital network, and perform specialized functions such as protection, control, monitoring, or automation of electrical systems.

A motor starter generally serves a more straightforward function, primarily focused on starting and stopping motors rather than engaging in sophisticated communication and processing tasks that are characteristic of IEDs. While some advanced motor starters can have communication capabilities, they often do not possess the full range of functionalities or the level of intelligence typically associated with IEDs in substation automation.

In contrast, protective relays, the substation communication bus, and logical nodes all embody the characteristics of IEDs. Protective relays actively monitor electrical parameters, make decisions based on preset conditions, and communicate status information. A substation communication bus is a crucial infrastructure transport layer for data within the system, while logical nodes represent the structural aspect of function definitions in IEC 61850 that facilitate communication and interoperability among various IEDs. Therefore, motor starters, while important for operational functions, are the least aligned with the IED classification in this context.