Polyvinyl chloride (PVC) insulation is widely used in low-voltage cable designs. PVC compounds can be formulated for general-purpose use, increased heat resistance or improved cold resistance.
The table below compares typical PVC insulation properties. Values are indicative and should be checked against the cable manufacturer’s datasheet for the exact compound and cable construction being specified.
PVC insulation material comparison
| Property | PVC Polyvinyl chloride compounds | PVC 90 °C Heat-resistant | PVC 105 °C Heat-resistant | PVC cold-resistant |
|---|---|---|---|---|
| Density, g/cm3 | 1.35-1.5 | 1.3-1.5 | 1.3-1.5 | 1.2-1.5 |
| Breakdown voltage, kV/mm at 20 °C | 25 | 25 | 25 | 25 |
| Specific volume resistivity, Ω cm at 20 °C | 1013-1015 | 1012-1015 | 1012-1015 | 1012-1015 |
| Dielectric constant, 50 Hz at 20 °C | 3.6-6 | 4-6.5 | 4.5-6.5 | 4.5-6.5 |
| Dielectric loss factor, tan δ | 4 × 10-2 to 1 × 10-1 | 4 × 10-2 to 1 × 10-1 | 4 × 10-2 to 1 × 10-1 | 4 × 10-2 to 1 × 10-1 |
| Permanent working temperature, °C | -30 to +70 | -20 to +90 | -20 to +105 | -40 to +70 |
| Short-time temperature, °C | +100 | +120 | +120 | +100 |
| Melt temperature, °C | >140 | >140 | >140 | >140 |
| Flame resistance | Self-extinguishing | Self-extinguishing | Self-extinguishing | Self-extinguishing |
| Oxygen index, LOI (% O2) | 23-42 | 23-42 | 24-42 | 24-42 |
| Heating value H0, MJ/kg | 17-25 | 16-22 | 16-20 | 17-24 |
| Thermal conductivity, W/(K·m) | 0.17 | 0.17 | 0.17 | 0.17 |
| Corrosive gases in case of fire | Hydrogen chloride | Hydrogen chloride | Hydrogen chloride | Hydrogen chloride |
| Radiation resistance, max Mrad | 80 | 80 | 80 | 80 |
| Tensile strength, N/mm2 | 10-25 | 10-25 | 10-25 | 10-25 |
| Elongation at break, % | 130-350 | 130-350 | 130-350 | 130-350 |
| Shore hardness | 70-95 (A) | 70-95 (A) | 70-95 (A) | 70-95 (A) |
| Abrasion resistance | Medium | Medium | Medium | Medium |
| Water absorption, % | 0.4 | 0.4 | 0.4 | 0.4 |
| Halogen free | No | No | No | No |
| Weather resistance | Medium; black compounds good | Medium; black compounds good | Medium; black compounds good | Medium; black compounds good |
| Cold resistance | Moderate-good | Moderate-good | Moderate-good | Very good |
Design notes
PVC compounds are self-extinguishing and widely available, but they are not halogen free and can release hydrogen chloride during fire. Where smoke, toxicity or corrosive gas behaviour is critical, compare PVC against LSZH or other halogen-free compounds and check the project’s fire-performance requirements.