Dielectric absorption ratio
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The dielectric absorption ratio is the ratio of two insulation resistance readings taken a short interval apart early in a direct-voltage test, the later reading divided by the earlier one. [1] Annex A of IEEE 43-2013 describes a ratio of this kind that divides the one-minute reading by a reading taken at 30 s. [2]
Usage
IEEE 43-2013 treats such shorter-time ratios as informative variants of the polarization index and states that no agreed pass or fail criteria exist for them. [3] ANSI/NETA ATS-2025 nevertheless uses a dielectric absorption ratio in evaluating rotating machinery. [4]
See also
Related entries are the polarization index, formed from readings at 10 min and 1 min, and insulation resistance. [5] [6]
Notes
- Electrical Testing Reference editorial taxonomy, 2026-10 edition. The dielectric absorption ratio is the ratio of two insulation resistance readings taken a short time apart early in a direct-voltage test, the later reading divided by the earlier one. Datum gloss.dielectric-absorption-ratio.definition
- IEEE 43-2013, clause A.1. One variant in Annex A of IEEE 43-2013 divides the one-minute insulation resistance by a reading taken thirty seconds after the voltage is applied.Value: 30 s. Datum tests.polarization-index-and-dielectric-absorption.dar-thirty-second
- IEEE 43-2013, clause Annex A. Annex A of IEEE 43-2013 describes variants of the polarization index built on shorter reading times and states that no agreed pass or fail criteria exist for them. Datum tests.polarization-index-and-dielectric-absorption.annex-variants
- ANSI/NETA ATS-2025, clause 7.15.1.B.2. ANSI/NETA ATS-2025 uses a dielectric absorption ratio for rotating machinery, a measure that IEEE 43-2013 describes only as an informative variant. Datum tests.polarization-index-and-dielectric-absorption.ats-dar
- IEEE 43-2013, clause 5.4. IEEE 43-2013 defines the polarization index as the insulation resistance read after ten minutes of applied voltage divided by the insulation resistance read after one minute. Datum tests.polarization-index-and-dielectric-absorption.pi-definition
- IEEE 43-2013, clause 5.4. The later of the two readings that make up the polarization index under IEEE 43-2013 is taken ten minutes after the test voltage is applied.Value: 10 min. Datum tests.polarization-index-and-dielectric-absorption.ten-minute
Data records
- The dielectric absorption ratio is the ratio of two insulation resistance readings taken a short time apart early in a direct-voltage test, the later reading divided by the earlier one.
Sources
- ANSI/NETA ATS-2025, Acceptance Testing Specifications for Electrical Power Equipment and Systems, 2025 edition, NETA. Cited: clause 7.15.1.B.2. Held as: Purchased single-user copy. Publisher page
- Electrical Testing Reference editorial taxonomy, Electrical Testing Reference editorial taxonomy of test methods, 2026-10 edition, Electrical Testing Reference. Held as: Own observation.
- IEEE 43-2013, Recommended Practice for Testing Insulation Resistance of Electric Machinery, 2013 edition, IEEE. Cited: clause A.1; clause Annex A; clause 5.4; clause 5.3. Held as: Purchased single-user copy. Publisher page
Obtaining the documents
- ANSI/NETA ATS-2025: publisher catalog or sales page
- IEEE 43-2013: publisher catalog or sales page
Changelog (14 entries)
| Date | Revision | Change | Reason | By |
|---|---|---|---|---|
| 2026-10-13 | created (gloss.dielectric-absorption-ratio.definition) | editorial definition of general physics (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (gloss.dielectric-absorption-ratio.definition) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent | |
| 2026-10-13 | 1 | created | hand-written exemplar for the article generator (Task 10) | agent |
| 2026-10-13 | created (tests.insulation-resistance.one-minute-reading) | method fact restated from the licensed-copy digest (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (tests.insulation-resistance.one-minute-reading) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent | |
| 2026-10-13 | created (tests.polarization-index-and-dielectric-absorption.annex-variants) | method fact restated from the licensed-copy digest (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (tests.polarization-index-and-dielectric-absorption.annex-variants) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent | |
| 2026-10-13 | created (tests.polarization-index-and-dielectric-absorption.ats-dar) | method fact from the IEEE 43-2013 digest mapping section, which compares the ATS-2025 rotating-machinery clauses with IEEE 43-2013 (Task 10 exemplars) | agent | |
| 2026-10-13 | created (tests.polarization-index-and-dielectric-absorption.dar-thirty-second) | method fact restated from the licensed-copy digest (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (tests.polarization-index-and-dielectric-absorption.dar-thirty-second) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent | |
| 2026-10-13 | created (tests.polarization-index-and-dielectric-absorption.pi-definition) | method fact restated from the licensed-copy digest (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (tests.polarization-index-and-dielectric-absorption.pi-definition) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent | |
| 2026-10-13 | created (tests.polarization-index-and-dielectric-absorption.ten-minute) | method fact restated from the licensed-copy digest (Task 10 exemplars) | agent | |
| 2026-10-13 | reviewed (tests.polarization-index-and-dielectric-absorption.ten-minute) | fresh-context review task-10-exemplars-review.md + fix round 1 | agent |
Cite this page
Cite the governing standard for the fact itself; cite this page as the finding aid.
Permanent revision URL: https://www.electricaltestingreference.com/glossary/dielectric-absorption-ratio/rev/1/. Current version: https://www.electricaltestingreference.com/glossary/dielectric-absorption-ratio/.
Plain
"Dielectric absorption ratio." Electrical Testing Reference. Revision 1, 2026-10-13. https://www.electricaltestingreference.com/glossary/dielectric-absorption-ratio/rev/1/.
Legal (Bluebook, internet source)
Electrical Testing Reference, Dielectric absorption ratio (rev. 1, Oct. 13, 2026), https://www.electricaltestingreference.com/glossary/dielectric-absorption-ratio/rev/1/.
BibTeX
@misc{etr-glossary-dielectric-absorption-ratio-rev1,
title = {Dielectric absorption ratio},
howpublished = {\url{https://www.electricaltestingreference.com/glossary/dielectric-absorption-ratio/rev/1/}},
organization = {Electrical Testing Reference},
publisher = {Electrical Testing Reference},
year = {2026},
note = {Revision 1; last substantive change 2026-10-13}
} Wikipedia
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