TS EN IEC 61869-99/AC

TS EN IEC 61869-99/AC is a corrigendum record in the instrument transformer field, focused on terminology. The title shows that it belongs to the glossary portion of the instrument transformer series, where the main purpose is to clarify the meaning and use of core terms associated with current and voltage transformers. In technical work, a controlled vocabulary reduces ambiguity in design, testing, procurement, and documentation by ensuring that the same term refers to the same concept.

Why terminology matters in instrument transformers

Instrument transformers scale high current or high voltage down to standardized values for measurement and protective functions. The terminology around this subject is closely tied to concepts such as ratio, accuracy class, primary and secondary windings, error, burden, and insulation. A glossary-style part gives these concepts a consistent technical meaning, which helps align product descriptions, laboratory reports, and project specifications across different equipment types.

How this record should be understood

The AC designation indicates a correction rather than a standalone technical rule set, so this listing should be read as a terminology-related update linked to the main document. In practical terms, it supports clearer and more consistent naming within the electrical measurement chain. It does not, by itself, establish an independent body of requirements; instead, it relates to the glossary content of the instrument transformer standard family.

• Covers terminology used for current and voltage instrument transformers.
• A glossary-oriented part of the instrument transformer series.
• Supports a shared technical language for measurement and protection work.
• As a corrigendum, it should be read together with the underlying glossary document.