Dielectric loss
Updated 2026-10-27
Data records
- Dielectric loss is the energy an insulating material dissipates as heat when it is subjected to an alternating electric field. It arises from the resistive component of the current through the insulation, the part that flows in phase with the applied voltage rather than in quadrature with it as a capacitive current does.
- In power factor testing practice the instrument measures both the magnitude and the phase angle of the current drawn by the insulation under the applied voltage and resolves that current into real and quadrature components. The real component represents the dielectric losses, which relate to contamination or deterioration of the dielectric.
Elsewhere in the family
- Insulation Power Factor Dissipation Factor related entry on Circuit Breaker Reference
- Insulation Power Factor Dissipation Factor related entry on Electrical Testing Reference
- Insulation Power Factor Dissipation Factor related entry on Motor Testing Reference
- Insulation Power Factor Dissipation Factor related entry on Revenue Metering Reference
- Insulation Power Factor Dissipation Factor related entry on Switchgear Testing Reference
- Insulation Power Factor Dissipation Factor related entry on Transformer Testing Reference
- Cable Tan Delta related entry on Electrical Testing Reference
Sources
- Doble article, 100 Years of Doble: A Quick History of Power Factor Testing of Power Transformers, web page edition, Doble. Held as: Public page. 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.
Changelog (4 entries)
| Date | Revision | Change |
|---|---|---|
| 2026-10-27 | created (gloss.dielectric-loss.definition) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (gloss.dielectric-loss.definition) | |
| 2026-10-27 | created (gloss.dielectric-loss.usage) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (gloss.dielectric-loss.usage) |
Cite this page
Cite the governing standard for the fact itself; cite this page as the finding aid.
"Dielectric loss." Test Instrument Reference. 2026-10-27. https://www.testinstrumentreference.com/glossary/dielectric-loss/.
Test Instrument Reference, Dielectric loss (Oct. 27, 2026), https://www.testinstrumentreference.com/glossary/dielectric-loss/.
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title = {Dielectric loss},
howpublished = {\url{https://www.testinstrumentreference.com/glossary/dielectric-loss/}},
organization = {Test Instrument Reference},
publisher = {Test Instrument Reference},
year = {2026},
note = {last substantive change 2026-10-27}
}{{cite web |title=Dielectric loss |website=Test Instrument Reference |publisher=Test Instrument Reference |url=https://www.testinstrumentreference.com/glossary/dielectric-loss/ |date=2026-10-27 |access-date=}}