ASTM D7894_D7894M-19 - Standard Test Method for Thermal Endurance of Coating Powders Used for Integral Bus Bar Insulation Systems

1.1 This test method provides a procedure for evaluating thermal endurance of coating powders by determining the length of aging time at selected elevated temperatures required to achieve dielectric breakdown at room temperature at a pre-determined proof voltage. Thermal endurance is expressed in terms of a temperature index.

1.2 This test method is applicable to insulating powders used over a substrate material of copper or aluminum.

1.3 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems is likely to result in non-conformance with the standard.

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 Section 7.

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.