IEEE PC37.04b/D12

PC37.04b/D12 is a technical standard focused on voltage circuit breakers rated on a symmetrical current basis, with particular attention to how transient recovery voltage is described for harmonization with IEC 60056. For power, energy, and industrial applications, this document helps align terminology and rating practice in breaker specification and evaluation. It is especially relevant where consistent definitions support equipment comparison, procurement, and engineering review across different standards frameworks.

Overview of PC37.04b/D12

This standard addresses a specific aspect of circuit breaker rating: the way transient recovery voltage is described when symmetrical current ratings are used. By refining that description, PC37.04b/D12 supports clearer technical interpretation and more consistent application of breaker requirements. The document is closely tied to voltage circuit breakers and their performance under interruption conditions, making it useful in contexts where precise rating language matters for design documentation, testing, and standards alignment.

Typical use cases

PC37.04b/D12 is typically used when specifying, comparing, or reviewing voltage circuit breakers for power-system applications. It may be relevant for utilities, switchgear engineering, and industrial installations that depend on interruption ratings and recovery-voltage definitions. The standard can also support technical work involving equipment selection, test planning, and documentation where harmonized terminology helps ensure that breaker ratings are interpreted consistently across projects and procurement processes.

Why it matters

For engineers and buyers, PC37.04b/D12 helps reduce ambiguity in how breaker performance is described and assessed. Clear definitions of transient recovery voltage can improve consistency in compliance checks, product comparison, and acceptance testing. That matters in high-voltage applications, where rating language influences safety margins, coordination studies, and equipment suitability. As an inactive standard, it may also serve as a reference point for legacy specifications and historical documentation.

• Voltage circuit breaker rating terminology
• Symmetrical current basis
• Transient recovery voltage description
• IEC 60056 harmonization context
• Specification and testing reference