ASTM D2477-07(2020)

Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Insulating Gases at Commercial Power Frequencies

SIGNIFICANCE AND USE
4.1 The dielectric breakdown voltage and dielectric strength of an insulating gas in a uniform field depends primarily on the molecular structure of the gas. As different gases are mixed either by plan or by contamination, any change in dielectric breakdown voltage and dielectric strength will depend on both the nature and proportion of the individual gases. This test method uses plane and spherical electrodes which provide a nearly uniform field (see Appendix) in the area of electrical discharge. It is suitable for determining the dielectric breakdown voltage and dielectric strength of different gases and mixtures thereof for research and application evaluations and also as a field test. A more complete discussion of the significance of the dielectric strength test is given in the Appendix.
SCOPE
1.1 This test method covers the determination of the dielectric breakdown voltage and dielectric strength of insulating gases used in transformers, circuit breakers, cables, and similar apparatus as an insulating medium. The test method is applicable only to gases with boiling points below room temperature at atmospheric pressure.  
1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.3 Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA's website — http://www.epa.gov/mercury/faq.htm for additional information. Users should be aware that selling mercury and/or mercury containing products into your state may be prohibited by state law.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2020
• ICS: 29.040.20 - Insulating gases
• Technical Committee: D27 - Electrical Insulating Liquids and Gases
• Drafting Committee: D27.05 - Electrical Test

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D2477 − 07 (Reapproved 2020)
Standard Test Method for
Dielectric Breakdown Voltage and Dielectric Strength of
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Insulating Gases at Commercial Power Frequencies
This standard is issued under the fixed designation D2477; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
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1.1 This test method covers the determination of the dielec- 2.1 ASTM Standards:
tric breakdown voltage and dielectric strength of insulating D2864 Terminology Relating to Electrical Insulating Liq-
gases used in transformers, circuit breakers, cables, and similar uids and Gases
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apparatus as an insulating medium. The test method is appli-
2.2 IEEE Standard:
cableonlytogaseswithboilingpointsbelowroomtemperature
No. 4 Standard Techniques for High Voltage Testing
at atmospheric pressure.
2.3 ASTM Adjuncts:
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Dielectric cell assembly and detail (2 drawings)
1.2 This standard may involve hazardous materials,
operations, and equipment. This standard does not purport to
3. Terminology
address all of the safety concerns, if any, associated with its
use. It is the responsibility of the user of this standard to 3.1 Definitions:
establish appropriate safety, health, and environmental prac-
3.1.1 For definitions of terms used in this test method, refer
tices and determine the applicability of regulatory limitations to Terminology D2864.
prior to use.
4. Significance and Use
1.3 Mercury has been designated by EPA and many state
agencies as a hazardous material that can cause central
4.1 The dielectric breakdown voltage and dielectric strength
nervous system, kidney and liver damage. Mercury, or its
of an insulating gas in a uniform field depends primarily on the
vapor, may be hazardous to health and corrosive to materials.
molecular structure of the gas. As different gases are mixed
Caution should be taken when handling mercury and mercury
either by plan or by contamination, any change in dielectric
containing products. See the applicable product Material
breakdown voltage and dielectric strength will depend on both
Safety Data Sheet (MSDS) for details and EPA’s website —
the nature and proportion of the individual gases. This test
http://www.epa.gov/mercury/faq.htm for additional informa-
method uses plane and spherical electrodes which provide a
tion. Users should be aware that selling mercury and/or
nearly uniform field (see Appendix) in the area of electrical
mercury containing products into your state may be prohibited
discharge. It is suitable for determining the dielectric break-
by state law.
down voltage and dielectric strength of different gases and
1.4 This international standard was developed in accor-
mixtures thereof for research and application evaluations and
dance with internationally recognized principles on standard-
also as a field test. A more complete discussion of the
ization established in the Decision on Principles for the
significance of the dielectric strength test is given in the
Development of International Standards, Guides and Recom-
Appendix.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
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This test method is under the jurisdiction of ASTM Committee D27 on Standards volume information, refer to the standard’s Document Summary page on
Electrical Insulating Liquids and Gases and is the direct responsibility of Subcom- the ASTM website.
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mittee D27.05 on Electrical Test. Available from The Institute of Electrical and Electronic Engineers, Inc.
Current edition approved Nov. 1, 2020. Published November 2020. Originally (IEEE), 445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-1331.
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approved in 1966. Last previous edition approved in 2012 as D2477 – 07(2012). Detaileddrawingsofthisapparatusareavailableatanominalcostfrom:ASTM
DOI: 10.1520/D2477-07R20. International Headquarters. Order Adjunct No. ADJD2477-E-PDF.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D2477 − 07 (2020)
5. Apparatus 5.2.1 Vacuum Pump— The vacuum pump shall have suffi-
cient pumping capacity to be able to evacuate the test cell to a
5.1 Electrical Apparatus:
pressure below 0.133 kPa (1 torr).
5.1.1 Transformer— The desired test volt
...