Значение и использование

The dielectric breakdown voltage of the sleeving is of importance as a measure of its ability to withstand electrical stress without failure. This value does not correspond to the dielectric breakdown voltage expected in service, but is of value in comparing different materials or different lots, in controlling manufacturing processes or, when coupled with experience, for a limited degree of design work. The comparison of dielectric breakdown voltage of the same sleeving before and after environmental conditioning (moisture, heat, and the like) gives a measure of its ability to resist these effects. For a more detailed discussion, refer to Test Method D149.

Область применения

1.1 These test methods cover procedures for testing electrical insulating sleeving comprising a flexible tubular product made from a woven textile fibre base, such as cotton, rayon, nylon, or glass, thereafter impregnated, or coated, or impregnated and coated, with a suitable dielectric material.

1.2 The procedures appear in the following sections:

ProceduresSections Brittleness Temperature18 to 21 Compatibility of Sleeving with Magnet Wire Insulation45 to 59 Conditioning 6 Dielectric Breakdown Voltage12 to 17 Dielectric Breakdown Voltage After Short-Time Aging29 to 33 Dimensions 7 to 11 Effect of Push-Back After Heat Aging73 to 78 Flammability22 to 28 Hydrolytic Stability66 to 72 Oil Resistance34 to 37 Selection of Test Material5 Solvent Resistance60 to 65 Thermal Endurance38 to 44

1.3 The values stated in inch-pound units, except for °C, are to be regarded as the standard. The values in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.4 This is a fire-test-response standard. See Sections 22 through 28, which are the procedures for flammability tests.

1.5 This standard measures and describes the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products or assemblies under actual fire conditions.

1.6 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. For specific hazard statements, see 45.2 and 63.1.1.

Note 1—This standard resembles IEC 60684-2, Specification for Flexible Insulating Sleeving—Part 2 Methods of Test, in a number of ways, but is not consistently similar throughout. The data obtained using either standard may not be technically equivalent.

1.7 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.

45.1 These test methods evaluate the degrading effects, if any, of sleeving on magnet wire insulation.

45.2 Warning—These procedures include the hazardous operation of the use of glass test tubes in a heated oven.

66.1 This procedure evaluates the permanent effects of prolonged exposure to moisture at elevated temperatures by means of a visual and electrical test. It is limited to sizes of sleeving that can be conveniently conditioned in test tubes (about size 0 maximum). It is possible to evaluate larger sizes if chambers capable of maintaining the prescribed exposure conditions are available.

73.1 While possibly applicable to other types of sleeving of an elastomeric nature, this test method applies principally to silicone elastomer sleeving.