IEC 62631-3-4:2019 covers procedures for the determination of insulation resistance and volume resistivity of insulating materials by applying DC-voltage and temperatures up to 800 °C. The typical application materials include high temperature mica plate and alumina ceramics.
This edition of IEC 62631-3-4 cancels and replaces IEC 60345 “Method of test for electrical resistance and resistivity of insulating materials at elevated temperatures”, published in 1971. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC 60345:
- The revised standard becomes part of the series IEC 62631-3-x. Title of the standard is changed and adapted to the series as Part 3-4.
- Clauses 2 Normative references, 3 Terms and definitions, and 4 Significance are added.
- Subclauses 5.2 Power supply, Voltage, 18.104.22.168 Number of test specimens and 22.214.171.124 Conditioning and pre-treatment of test specimens are added.
- In 5.3.5 Special precautions during measurements, errors analysis in the measurement of current are modified, and aligned with IEC 62631-3-1.
- In 6.2 Increasing the temperature by steps (method B), the method for more than one specimen is removed.
- The standard atmospheric conditions for testing and conditioning, especially the temperature, are replaced according to IEC 60212.
- The circuit diagram of test apparatus is modified, and the structure diagram and pictures of test apparatus are added in Annex A.
- The orders of part clauses are adjusted.