The electrical properties of resin-coated glass fabrics are affected by their temperature and moisture content. For this reason it is necessary to control these properties for a specified time immediately prior to testing in order to attain reasonably good reproducibility of test values. The time of exposure to the conditioning atmosphere must be long enough to permit the test specimen to reach a relatively stable value. Usually the moisture content of these materials has little effect on the mechanical properties.

1. Scope

1.1 These test methods cover procedures for the testing of resin-coated glass fabrics and glass fabric tapes (Note 1) to be used as electrical insulation.

Note 1—Methods of testing varnished cloths and tapes are given in Methods D295.

1.2 The warp threads in fabrics are the threads that are parallel with the length dimension as manufactured.

1.3 The procedures appear as follows:

1.4 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.

1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. Specific warning statement are given in 35.1.1 and 58.1.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies

D150 Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation

D295 Test Methods for Varnished Cotton Fabrics Used for Electrical Insulation

D374 Test Methods for Thickness of Solid Electrical Insulation

D828 Test Method for Tensile Properties of Paper and Paperboard Using Constant-Rate-of-Elongation Apparatus

D1711 Terminology Relating to Electrical Insulation

D1830 Test Method for Thermal Endurance of Flexible Sheet Materials Used for Electrical Insulation by the Curved Electrode Method

D3487 Specification for Mineral Insulating Oil Used in Electrical Apparatus

D5032 Practice for Maintaining Constant Relative Humidity by Means of Aqueous Glycerin Solutions

D5423 Specification for Forced-Convection Laboratory Ovens for Evaluation of Electrical Insulation

E104 Practice for Maintaining Constant Relative Humidity by Means of Aqueous Solutions

IEEE Standard

Keywords

breaking strength; coated glass fabric; dielectric breakdown voltage; dissipation factor; heat aging; permittivity; thermal endurance; thread count; Oleoresinous varnish-coated glass fabric/tape; Permittivity (dielectric constant)--electrical insulating materials; Permittivity method; Resins; Thermal endurance--electrical insulating materials; Breaking strength/tenacity--electrical insulating materials; Dielectric breakdown voltage; Dissipation factor; Electrical insulating tape; Glass electrical/electronic insulation; Heat aging; Insulating tape; Oil resistance--electrical insulating materials; Thread count; Varnish-coated glass fabric/tape

ICS Code

ICS Number Code 29.035.30 (Glass and ceramic insulating materials)

Citing ASTM Standards

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