IEC 60455-2:2023

Overview

IEC 60455-2:2023 - Resin based reactive compounds used for electrical insulation - Part 2: Methods of test specifies standardized test methods for resin based reactive compounds, their components and cured compounds used in electrical insulation. This fourth edition (2023) cancels and replaces the 2015 edition and introduces technical revisions, including new test methods related to IEC 60455‑3‑8 and additional/updated resin test procedures. The standard is essential for consistent characterization of processing, mechanical, thermal, chemical and electrical properties of insulating resins (epoxy, unsaturated polyester and others).

Key Topics and Technical Requirements

IEC 60455-2:2023 defines methods of test across a broad range of material attributes. Major technical topics include:

• Preparing and conditioning of test specimens, sequence of tests and required test reporting.
• Raw component tests: flash point, density, viscosity, volatile organic content, water content (Karl Fischer), epoxide/isocyanate equivalents, hydroxyl/acid/amine values.
• Processing and cure behaviour: isothermal viscosity increase (processing time), pot life, gel time, shelf life, exothermic temperature rise, curing in presence of water, degree of cure.
• Cured-material properties:
  • Mechanical: tensile, compressive, flexural, impact, hardness.
  • Thermal: glass transition, thermal conductivity, thermal shock, loss of mass, temperature index.
  • Chemical: water absorption, resistance to liquid chemicals, mould growth, water vapour permeability.
  • Electrical: volume resistivity, dielectric dissipation factor (tan δ), relative permittivity, breakdown voltage/electric strength, proof tracking index (PTI), electrolytic corrosion.
• Special tests: curing in thick layers, emissions during curing, total volume shrinkage, filler/ash/chlorine content and flammability assessments.
• Health & safety guidance (informative annex).

Practical Applications - Who Uses This Standard

IEC 60455-2:2023 is used by:

• Manufacturer R&D and quality control teams to validate resin formulations, processing windows and batch consistency.
• Test laboratories and certification bodies for accredited testing and conformity assessments of insulating compounds.
• Cable accessory and electrical component designers to select materials that meet mechanical, thermal and dielectric performance requirements.
• Procurement and specifications engineers to define acceptance criteria in supplier contracts and product standards.
• Utilities and OEMs evaluating long-term reliability (hydrolytic stability, electrical aging).

Benefits include reproducible performance data, improved safety, reduced field failures and easier regulatory/contractual compliance.

Related Standards

• IEC 60455 series (other Parts) - complementary methods and product requirements.
• IEC 60455‑3‑8 - specifically referenced in this edition for newly introduced test methods.

Using IEC 60455-2:2023 helps ensure that resin based reactive compounds used for electrical insulation are tested consistently for dielectric properties, curing behaviour, thermal stability and mechanical integrity, supporting safe and reliable electrical systems.