Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D2633-21 – Standard Test Method Technical Guide
ASTM D2633-21 provides standardized test methods for evaluating thermoplastic insulations and jackets in wire and cable applications. These methods cover a range of physical, electrical, and thermal properties to ensure material performance and reliability. Where dual units are provided, the first set is standard.
📐 Standard Test Methods and Scope
The standard includes various test methods for different properties. Table 1 lists the test methods and their respective sections in the standard.
| 🟦 Test Method | 📏 Section(s) |
|---|---|
| Cold Bend Test | 75 to 77 |
| Dielectric Strength Retention Test | 45 to 51 |
| Electrical Tests of Insulation | 17 to 29 |
| Heat Distortion Test | 74 |
| Heat Shock Test | 73 |
| Insulation Resistance Test | 30 to 37 |
| Partial-discharge Extinction Level Test | 38 to 44 |
| Physical Tests of Insulation and Jackets | 5 to 16 |
| Flammability (Test Method D8354) | 63 |
| Surface Resistivity Test | 64 to 67 |
| Thermal Tests | 72 to 77 |
| Track Resistance Test | 78 to 81 |
| U-bend Discharge Test | 68 to 71 |
| Vertical Flame Test | 63 |
| Water Absorption Tests, Accelerated | 52 to 62 |
These tests are performed on insulated or jacketed wire or cable to determine the properties of the insulation or jacket material itself, not the conductor or cable. The standard does not apply to flexible cords.
⚙️ Test Procedures and Key Parameters
The standard references several ASTM standards for specific test procedures. Table 2 lists these referenced standards.
| 🟦 Referenced Standard | 📐 Description |
|---|---|
| D149 | Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies |
| D150 | AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation |
| D257 | DC Resistance or Conductance of Insulating Materials |
| D374/D374M | Thickness of Solid Electrical Insulation |
| D471 | Rubber Property—Effect of Liquids |
| D573 | Rubber—Deterioration in an Air Oven |
| D638 | Tensile Properties of Plastics |
| D1248 | Polyethylene Plastics Extrusion Materials for Wire and Cable |
| D1711 | Terminology Relating to Electrical Insulation |
| D2132 | Dust-and-Fog Tracking and Erosion Resistance of Electrical Insulating Materials |
| D3755 | Dielectric Breakdown Voltage and Dielectric Strength Under Direct-Voltage Stress |
⚠️ Important Note: Electrical tests on insulation and water-absorption tests do not apply to products having a separator between the conductor and the insulation. Always consult the product specification for the specific material.
💡 Tip: For fire test safety caveats, refer to Test Method D8354, and for specific hazards, see Section 4 of the standard. Ensure all safety practices are followed during testing.
Physical tests of insulation and jackets are covered in Sections 5 to 16, which include procedures for tensile strength, elongation, and other mechanical properties. These tests are crucial for assessing material durability under operational