IEEE PC37.105/D2, July 2023 is a draft standard focused on qualifying Class 1E protective relays and auxiliaries for nuclear power generating stations and other nuclear facilities. It addresses technical expectations for equipment used in safety-related applications where dependable operation and documented qualification are essential. By defining a common basis for evaluation, IEEE PC37.105/D2, July 2023 helps support consistent design, testing, and procurement decisions in nuclear engineering environments.

About IEEE PC37.105/D2, July 2023

This draft standard is intended to guide qualification of protective relays and auxiliary devices assigned to Class 1E service in nuclear installations. Its technical context is tied to safety-related electrical systems, where equipment must be shown suitable for the required duty and operating conditions. IEEE PC37.105/D2, July 2023 is relevant for engineers, specifiers, and reviewers who need a structured reference for assessing relay and auxiliary performance, reliability, and conformity within a nuclear power application.

Where is IEEE PC37.105/D2, July 2023 used?

IEEE PC37.105/D2, July 2023 is typically used in the specification, qualification, and review of protective relay systems and associated auxiliaries for nuclear power generating stations and related nuclear facilities. It is relevant in safety-related electrical protection schemes, engineering change control, and procurement of Class 1E components. The standard may also support testing and documentation activities where relays, interface devices, or auxiliary equipment must demonstrate suitability for nuclear service conditions and operational expectations.

Importance in practice

In practice, the standard matters because Class 1E equipment must be selected and qualified with care to reduce risk and maintain consistent protective performance. IEEE PC37.105/D2, July 2023 can help align design intent, test evidence, and acceptance criteria across engineering teams and suppliers. For nuclear facilities, that consistency supports compliance efforts, improves configuration control, and helps ensure that protective relays and auxiliaries remain dependable for safety-related functions over their intended service life.

• Class 1E relay qualification
• Auxiliary device suitability
• Nuclear safety-related applications
• Testing and acceptance criteria
• Design and procurement reference