IEEE C37.2-2022

IEEE C37.2-2022 is the standard for electrical power system device function numbers, acronyms, and contact designations. It provides a common reference for identifying protective relays, control devices, and related equipment used in power and energy applications. By standardizing the way functions are named and marked, it helps engineers, manufacturers, and operators communicate more clearly and reduce confusion during design, documentation, installation, and maintenance.

IEEE C37.2-2022 overview

This technical document defines the function-numbering and designation system used for electrical power system devices. In practice, IEEE C37.2-2022 supports consistent labeling of devices and contacts so that diagrams, schematics, panels, and operating records can be interpreted in the same way across projects. The standard is especially relevant where protection, control, and switching functions must be documented with precision. It is a practical reference for teams working with power-system equipment and associated engineering records.

Typical use cases

IEEE C37.2-2022 is commonly used when preparing one-line diagrams, control schematics, relay setting documentation, and panel nameplates for power-system installations. It is useful for substations, generation facilities, industrial electrical systems, and utility control equipment where standardized device identifiers matter. The standard can also support procurement and engineering reviews by helping specify the expected function numbers, acronyms, and contact designations for protective and control devices used in electrical power networks.

Why this standard matters

Using IEEE C37.2-2022 helps improve consistency across design, construction, and maintenance workflows. Clear device designations can reduce misinterpretation, support safer switching and troubleshooting, and make compliance checking more straightforward. For organizations handling electrical power equipment, a shared naming system can also improve coordination between engineering teams, contractors, and operators. That consistency is valuable when comparing documentation, verifying equipment identity, or reviewing control and protection schemes over the life of a system.

• Function numbers for power-system devices
• Standard acronyms and device identifiers
• Contact designation guidance
• Protection and control documentation support
• Useful for schematics, panels, and relay records