IEC TS 62073:2016 PDF

Overview - IEC TS 62073:2016 (Hydrophobicity measurement)

IEC TS 62073:2016 provides guidance on the measurement of hydrophobicity of insulator surfaces. It applies to shed and housing materials of composite insulators used on overhead lines, substations and equipment, and to ceramic insulators with or without coatings. The technical specification describes three accepted measurement methods and defines how to document and assign hydrophobicity classes. The measured value represents the hydrophobicity at the time of measurement.

Key topics and requirements

• Scope and definitions
  • Defines key terms such as hydrophobicity, hydrophilicity, surface tension and static contact angle.
• Three measurement methods
  • Method A - Contact angle method: static and dynamic contact angle measurements (advancing/receding angles) to quantify surface wetting behavior.
  • Method B - Surface tension method: determination using standardized liquid mixtures to infer surface energy/tension of the insulator surface.
  • Method C - Spray method: visual/classification method suitable for in-service assessment of hydrophobicity.
• Evaluation and classification
  • Procedures for evaluating results and assigning a hydrophobicity class (HC) (criteria redefined in this edition; see clause 3.4 and Table 1 of the specification).
• Documentation and limitations
  • Requirements for recording test conditions and results, and annexes that describe applicability and limitations of each method (lab vs in-situ challenges).
• Edition changes
  • Terminology updated from “wettability” to hydrophobicity, and classification criteria were revised from the 2003 edition.

Practical applications and users

IEC TS 62073 is intended for:

• Utility and transmission engineers assessing insulator condition on overhead lines and substations.
• Insulator manufacturers and coating suppliers performing product qualification and quality control.
• High-voltage test laboratories conducting laboratory or in-service measurements.
• Maintenance and asset managers who evaluate performance degradation, hydrophobicity transfer materials (HTM) behavior, and pollution effects. Practical uses include condition monitoring, comparative product testing, acceptance testing after manufacture or coating, and research on aging and contamination effects.

Related guidance and notes

• The specification highlights that hydrophobicity is dynamic (affected by material type, surface roughness, ageing, contamination and environmental exposure). Measurements are non-destructive but can vary by location on an insulator; multiple measurement points are recommended.
• For implementation, consult IEC TS 62073:2016 clauses, normative annexes (A–D) and Table 1 for HC criteria. For broader context, also refer to IEC publications covering insulator testing and high-voltage equipment.