Transformer Testing Reference

Insulation resistance

Updated 2026-10-13

RelationshipsInsulation resistance is governed by IEEE/IEC C57.15-2017, IEEE C57.18.10-2021, IEEE C57.12.90-2021 and applies to no listed equipment.IEEE/IEC International Standard: Power transformers, Part 21: Standard requirements, terminology, and test code for step-voltage regulatorsIEEE/IEC C57.15-2017IEEE Standard Practices and Requirements for Semiconductor Power Rectifier TransformersIEEE C57.18.10-2021IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating TransformersIEEE C57.12.90-2021Insulation resistanceInsulation resistance
Relationships. Governing standards on the left, equipment classes the test applies to on the right, as recorded for this entry.
Relationships: relationships recorded for this entry.
RelationshipEntry
Governing standardIEEE/IEC C57.15-2017 (IEEE/IEC International Standard: Power transformers, Part 21: Standard requirements, terminology, and test code for step-voltage regulators)
Governing standardIEEE C57.18.10-2021 (IEEE Standard Practices and Requirements for Semiconductor Power Rectifier Transformers)
Governing standardIEEE C57.12.90-2021 (IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers)

Data records

Sources

  • ANSI/NETA ATS-2025, Acceptance Testing Specifications for Electrical Power Equipment and Systems, 2025 edition, NETA. Cited: clause 7.12.1.1.B.2; clause 7.2.2.B.2; clause 7.2.1.1.B.2. Held as: Purchased single-user copy. Publisher page
  • ANSI/NETA MTS-2023, Maintenance Testing Specifications for Electrical Power Equipment and Systems, 2023 edition, NETA. Cited: clause 7.12.1.1.B.2; clause 7.2.2.B.2; clause 7.2.1.1.B.2. Held as: Purchased single-user copy. Publisher page

Obtaining the documents

Changelog (6 entries)
DateRevisionChange
2026-10-13created (tests.insulation-resistance.equipment.regulator.acceptance)
2026-10-13created (tests.insulation-resistance.equipment.regulator.maintenance)
2026-10-13created (tests.insulation-resistance.equipment.transformer-fluid.acceptance)
2026-10-13created (tests.insulation-resistance.equipment.transformer-fluid.maintenance)
2026-10-13created (tests.insulation-resistance.equipment.transformer.acceptance)
2026-10-13created (tests.insulation-resistance.equipment.transformer.maintenance)

Cite this page

Cite the governing standard for the fact itself; cite this page as the finding aid.

"Insulation resistance." Transformer Testing Reference. 2026-10-13. https://www.transformertestingreference.com/tests/insulation-resistance/.