IEEE C92.2-1987

C92.2-1987 is a standards document on preferred voltage ratings for power, energy, and industry applications. It addresses how voltage levels are selected and identified for electrical systems, helping engineers, buyers, and specification writers work from consistent rating values. For equipment planning, system compatibility, and documentation, this standard supports clearer design decisions and reduces ambiguity when defining electrical supply and load requirements. As a superseded reference, C92.2-1987 may still be useful for legacy comparisons and historical technical work.

Overview of C92.2-1987

The purpose of C92.2-1987 is to define preferred voltage ratings used in electrical practice for power-related applications. In practical terms, it helps standardize voltage selection so that systems, apparatus, and associated specifications can be aligned around common rating values. That consistency is important when comparing equipment, preparing procurement documents, or reviewing legacy installations. The document is most relevant where voltage rating choices affect interoperability, insulation coordination, and general system planning across energy and industrial environments.

Typical use cases

This standard is typically consulted when specifying voltage levels for power equipment, industrial electrical systems, and related components that must operate within established rating conventions. It can also support engineering reviews for substations, distribution equipment, motors, control gear, and other installations where preferred voltage values influence system design. In procurement and asset documentation, C92.2-1987 may help ensure that namesplate ratings, drawings, and technical schedules use consistent electrical terminology and voltage references.

Why it matters

Preferred voltage ratings matter because they shape compatibility, safety margins, and consistency across electrical projects. Using a recognized standard helps reduce confusion during design, testing, and procurement, especially when multiple equipment types must work together. For legacy systems, C92.2-1987 can also provide a stable reference point when comparing older ratings or maintaining documentation over time. In regulated or controlled environments, that clarity can support better compliance, lower engineering risk, and more reliable specification management.

• Preferred voltage ratings
• Power and industrial applications
• Legacy technical reference
• Specification and procurement support