IEEE PC37.04-1999/Cor1/D3, May 2009 is a corrigendum to IEEE Std C37.04-1999, issued to clarify and correct technical content tied to ratings, requirements, and related terminology for power apparatus within the IEEE C37 family. For utilities, engineers, and procurement teams working with switchgear and other medium-voltage equipment, it helps keep specifications aligned and reduces the risk of using outdated wording. This makes IEEE PC37.04-1999/Cor1/D3, May 2009 a useful reference for controlled technical documentation.

About IEEE PC37.04-1999/Cor1/D3, May 2009

This corrigendum supports the original C37.04 standard by addressing corrections that may affect how equipment requirements are read and applied in practice. In the power, energy, and industry applications context, that can matter for design review, specification writing, and compliance checking. IEEE PC37.04-1999/Cor1/D3, May 2009 is not a broad new edition; rather, it is a focused update intended to improve precision in the underlying technical document and help users interpret the standard consistently.

Where is IEEE PC37.04-1999/Cor1/D3, May 2009 used?

This standard is typically used where electrical equipment specifications must match IEEE C37 requirements, especially in substation, switchgear, and medium-voltage power distribution work. It may be consulted by engineers preparing bid documents, by manufacturers reviewing product requirements, and by test or inspection teams checking conformity against the corrected text. In practice, IEEE PC37.04-1999/Cor1/D3, May 2009 supports clearer communication across design, sourcing, and acceptance workflows in utility and industrial power systems.

Importance in practice

In technical procurement and engineering, small wording corrections can affect ratings, interpretation, and acceptance criteria. Using IEEE PC37.04-1999/Cor1/D3, May 2009 helps organizations reduce ambiguity when comparing equipment, writing specifications, or verifying compliance with the IEEE C37 framework. It is especially useful when consistency across documents matters, since corrigenda help prevent misapplication of older text. For teams managing regulated or safety-relevant electrical equipment, that added clarity can lower design and purchasing risk.

• Corrigendum to IEEE Std C37.04-1999
• Corrected technical wording and requirements
• Relevant to power equipment and switchgear specifications
• Supports compliance, review, and procurement checks
• Inactive standard document in English