ASTM D4496-21e1

Standard Test Method for D-C Resistance or Conductance of Moderately Conductive Materials

SIGNIFICANCE AND USE
5.1 This test method is useful for the comparison of materials, as a quality control test, and for specification purposes.  
5.2 This test method is useful in the selection and use of materials in wires, cables, bushings, high-voltage rotating machinery, and other electrical apparatus in which shielding or the distribution of voltage stress is of value.  
5.3 Commercially available “moderately conductive” materials frequently are comprised of both conductive and resistive components (that is, cellulose fibers with colloidal carbon black particles attached to portions of the surfaces of those fibers, or discrete conductive particles adhered to the surfaces of electrical insulating polymers). Such commercially available materials are often manufactured in a manner that results in anisotropy of electrical conduction. Hence, the significance of tests using this test method depends upon the orientation of the specimen tested to the direction of the electric field and the relationship between this orientation and the orientation of the material in the electrical apparatus, which uses these materials.
SCOPE
1.1 This test method covers the determination of electrical resistance and electrical resistivity of materials that are generally categorized as moderately conductive and are neither good electrical insulators nor good conductors.  
1.2 This test method applies to the materials that exhibit volume resistivity in the range of 100 to 107 Ω-cm or surface resistivity in the range of 103 to 107 Ω (per square).  
1.3 This test method is designed for measurements at standard conditions of 23 °C and 50 % relative humidity, but its principles of operation can be applied to specimens measured at lower or higher temperatures and relative humidities.  
1.4 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.  Specific precautionary statements are given in 8.3.  
1.5 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-Dec-2020
• ICS: 29.050 - Superconductivity and conducting materials
• Technical Committee: D09 - Electrical and Electronic Insulating Materials
• Drafting Committee: D09.12 - Electrical Tests

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.
´1
Designation: D4496 − 21
Standard Test Method for
D-C Resistance or Conductance of Moderately Conductive
1
Materials
This standard is issued under the fixed designation D4496; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1
ε NOTE—Editorially updated adjunct stock code in December 2022.
1. Scope D374/D374MTest Methods for Thickness of Solid Electri-
cal Insulation
1.1 This test method covers the determination of electrical
D618Practice for Conditioning Plastics for Testing
resistance and electrical resistivity of materials that are gener-
D991Test Method for Rubber Property—Volume Resistiv-
allycategorizedasmoderatelyconductiveandareneithergood
ity Of Electrically Conductive and Antistatic Products
electrical insulators nor good conductors.
D1711Terminology Relating to Electrical Insulation
1.2 This test method applies to the materials that exhibit
2.2 ASTM Adjuncts:
0 7
volume resistivity in the range of 10 to 10 Ω-cm or surface
3
Carbon black test cell (two drawings)
3 7
resistivity in the range of 10 to 10 Ω (per square).
1.3 This test method is designed for measurements at
3. Terminology
standardconditionsof23°Cand50%relativehumidity,butits
3.1 Definitions:
principles of operation can be applied to specimens measured
3.1.1 moderately conductive—a solid material having vol-
at lower or higher temperatures and relative humidities.
0 7
ume resistivity between 10 and 10 Ω·cm.
1.4 This standard does not purport to address all of the
3.1.2 For definitions of the terms used, but not defined in
safety concerns, if any, associated with its use. It is the
this standard, refer to Terminology D1711.
responsibility of the user of this standard to establish appro-
3.2 Definitions of Terms Specific to This Standard:
priate safety, health, and environmental practices and deter-
3.2.1 steady state—for the purpose of this test method,
mine the applicability of regulatory limitations prior to use.
steady-state is attained if any rate of change in the observed
Specific precautionary statements are given in 8.3.
resistance (or conductance) averages less than 0.25%⁄s.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
4. Summary of Test Method
ization established in the Decision on Principles for the
4.1 Specimens of the test material are conditioned at pre-
Development of International Standards, Guides and Recom-
scribed conditions and subjected to direct-voltage stress. Re-
mendations issued by the World Trade Organization Technical
sistance or conductance is measured and used with the dimen-
Barriers to Trade (TBT) Committee.
sional aspects of the specimen to compute the resistivity of the
material.Theapparatusandtechniquesusedinthistestmethod
2. Referenced Documents
are selected in accordance with the general principles set forth
2
2.1 ASTM Standards:
in Test Methods D257 and D991.
D257Test Methods for DC Resistance or Conductance of
Insulating Materials
5. Significance and Use
5.1 This test method is useful for the comparison of
materials, as a quality control test, and for specification
1
This test method is under the jurisdiction of ASTM Committee D09 on
purposes.
Electrical and Electronic Insulating Materials and is the direct responsibility of
Subcommittee D09.12 on Electrical Tests. 5.2 This test method is useful in the selection and use of
Current edition approved Jan. 1, 2021. Published February 2021. Originally
materials in wires, cables, bushings, high-voltage rotating
approved in 1985. Last previous edition approved in 2013 as D4496 – 13. DOI:
10.1520/D4496-21E01.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from ASTM International Headquarters. Order Adjunct
Standards volume information, refer to the standard’s Document Summary page on No.ADJD4496-E-PDF. Original adjunct produced in 2015.Adjunct last revised in
the ASTM website. 2015.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
´1
D4496 − 21
machinery, and other electrical apparatus in which shielding or 7.2 Prior to testing, condition all specimens to equilibrium
the distribution of voltage stress is of value. in the standard laboratory atmosphere prescribed in Practice
D618. For many materia
...