Overview
IEC 62631-3-1:2023 defines a general DC method for measuring the volume resistance and volume resistivity of solid electrical insulating materials. This second edition updates and completes the first edition (2016) by incorporating missing editorial and technical text following the withdrawal of IEC 60093, and by aligning normative texts, informative notes, references and bibliography. The standard describes how to apply a DC voltage to a specimen, monitor the current response, and calculate resistive properties for material selection, quality control and research.
Key topics and technical requirements
- Scope and definitions: precise definitions of volume resistance (Ω) and volume resistivity (Ω·m) and discussion of polarization, conductivity and stray currents.
- DC test method: application of a DC voltage and measurement of the resulting current decay toward steady state; guidance on appropriate electrification times.
- Time dependence: for materials with volume resistivity below about 10 Ω·m, steady state is often reached within ~1 minute; higher-resistivity materials may require minutes to weeks to stabilize-test duration must account for this.
- Instrumentation and accuracy: requirements for power supplies, measurement equipment accuracy, guarding techniques and electrode design (including guarded electrode arrangements shown in the standard).
- Specimen preparation: recommended specimen dimensions, manufacturing, conditioning and pre-treatment to ensure reliable results.
- Calibration and verification: procedures for calibrating the measuring circuit and electrodes.
- Measurement procedure and calculations: stepwise method to determine volume resistance and compute volume resistivity from measured values.
- Reporting and quality: required test-report items and notes on repeatability and reproducibility.
- Polarization and measurement integrity: notes on avoiding spurious repeatability (allow sufficient time between repeated tests to avoid polarization effects).
Practical applications and users
IEC 62631-3-1 is used by:
- Test laboratories performing electrical characterization of insulating materials.
- Insulation and polymer manufacturers for material specification and quality control.
- R&D teams investigating dielectric/resistive behavior, aging and environmental effects (temperature, humidity).
- Product designers and engineers in power, electrical equipment and electronics industries who need reliable resistivity data for insulation selection and safety assessments.
- Certification bodies and procurement groups verifying material performance against standardized test methods.
Practical uses include material comparison, acceptance testing, lifetime/aging studies, and supporting dielectric design decisions where DC leakage or insulation resistance are critical.
Related standards
Normative references cited in IEC 62631-3-1:2023 include:
- IEC 60212 (standard conditions for testing)
- IEC 60455 series (resin-based compounds)
- IEC 60464 series (varnishes)
- IEC 61212 series (industrial materials – rods/tubes)
- ISO 868 (Shore hardness)
For accurate application, users should obtain the latest edition from the IEC Webstore and consult the referenced documents.
Open preview (PDF)Dielectric and resistive properties of solid insulating materials - Part 3-1: Determination of resistive properties (DC methods) - Volume resistance and volume resistivity - General method
