IEC 61039:2008

Overview

IEC 61039:2008 is an international standard published by the International Electrotechnical Commission (IEC) that provides a comprehensive classification system for insulating liquids. It delineates the detailed classification of the N family (insulating liquids), defined within class L (lubricants, industrial oils and related products) as per ISO 8681 and ISO 6743-99 standards. This classification covers a broad spectrum of insulating liquids including those derived from petroleum processing, synthetic chemical products, and both synthetic and natural esters.

The update from the previous edition focuses on expanding the classification to include the widest range of substances with current or potential application in electrical components, ensuring relevancy in modern electrotechnical applications.

Key Topics

• Classification Framework: The standard applies a structured coding system based on the ISO classification approach. This system uses letters and numbers to indicate the class, category, and additional identifying information of insulating liquids.

• Class Identification: Insulating liquids fall under Class L, which includes lubricants, industrial oils, and related products. Specific class letters include:

  • F: Fuels
  • S: Solvents and raw materials
  • L: Lubricants, industrial oils and related products (applicable class for insulating liquids)
  • W: Waxes
  • B: Bitumen

• Category Codes: Categories are coded by a sequence of four letters indicating:

  • The family (N for electrical insulation)
  • Application field (C - capacitors, T - transformers and switching equipment, S - low-temperature switching equipment, Y - cables)
  • Presence and concentration of antioxidant additives (U - none, T - trace amounts, I - significant amounts)
  • Fire point classification based on standard testing methods (O - fire point ≤ 300 °C, K - fire point > 300 °C, L - no detectable fire point)

• Identification Numbers: A seven-digit number following the category code specifies the IEC reference, IEC sub-classification, and other technical details to uniquely identify each insulating liquid type.

• Health & Safety: The standard advises careful handling of insulating liquids, noting potential irritations and emphasizing compliance with health and safety regulations. Disposal practices must align with environmental legislation to prevent ecological harm.

Applications

IEC 61039:2008 is crucial for manufacturers, suppliers, and users of insulating liquids in the electrotechnical industry. It facilitates:

• Standardized Product Identification: Ensures a common language for describing insulating liquids, aiding in specification, procurement, and regulatory compliance.

• Transformer and Switchgear Engineering: Supports the selection of appropriate insulating liquids with defined fire safety characteristics and additive content for power transformers, capacitors, cables, and switching equipment.

• Quality Control and Compliance: Enables uniform testing and classification aligned with IEC and ISO testing methods like flash point and fire point determination to ascertain product performance and safety.

• Environmental Management: Promotes proper handling and disposal protocols safeguarding operators and the environment.

Related Standards

IEC 61039:2008 interacts with several other IEC and ISO standards essential for insulating liquids and related electrotechnical applications:

• ISO 8681: Petroleum products and lubricants classification - Definition of classes
• ISO 6743-99: Lubricants, industrial oils, and related products classification general principles
• IEC 60296: Specifications for unused mineral insulating oils
• IEC 60076-14: Power transformers - Design and application of liquid-immersed transformers with high-temperature insulation
• IEC 60836: Specifications for unused silicone insulating liquids
• IEC 61100: Fire behaviour classification of insulating liquids
• ISO 2592: Flash and fire points determination methods

These interconnected standards ensure comprehensive guidance on the characteristics, testing, application, and classification of insulating liquids used in electrical equipment.

By employing IEC 61039:2008, stakeholders can ensure the correct classification and safe use of insulating liquids, thereby enhancing reliability and safety in electrical and electronic systems.