Cable Insulation Properties
HDPE Cable Insulation
Resin Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types of insulation have been employed. During recent years, there has been some consolidation in the types of insulation used.
This post provides some information on the more commonly used cable insulation materials.
Insulation Materials (PVC)
| Y | Yw | Yw | Yk |
PVC | PVC | PVC | PVC |
Polyvinylchloride Compounds | Heat-resistant 90oC | Heat-resistant 105oC | Cold Resistant |
Density g/cm3 | 1.35 - 1.5 | 1.3-1.5 | 1.3-1.5 | 1.2-1. |
Breakdown Voltage KV/mm (20oC) | 25 | 25 | 25 | 25 |
Specific Volume Resistivity Ω cm (20oC) | 1013-1015 | 1012-1015 | 1012-1015 | 1012-1015 |
Dielectric Constant 50 Hz (20oC) | 3.6-6 | 4-6.5 | 4.5-6.5 | 4.5-6.5 |
Dielectric Loss Factor (tan δ) | 4 x 10-2 to 1 x 10-1 | 4 x 10-2 to 1 x 10-1 | 4 x 10-2 to 1 x 10-1 | 4 x 10-2 to 1 x 10-1 |
Working Temperature | Permanent oC | -30 +70 | -20 +90 | -20 +105 | -40 +70 |
Short Time oC | +100 | +120 | +120 | +100 |
Melt Temperature +oC | >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-1 | 17-25 | 16-22 | 16-20 | 17-24 |
Thermal Conductivity W.K-1.m-1 | 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: Good) | Medium (Black: Good) | Medium (Black: Good) | Medium (Black: Good) |
Cold Resistance | Moderate - Good | Moderate - Good | Moderate - Good | Very Good |
Insulation Materials (PE)
| 2Y | 2Y | 2X | O2Y |
LDPE | HDPE | VPE | |
Low density Polyethylene | High density Polyethylene | Cross Linked Polyethylene | Foamed Polyethylene |
Density g/cm3 | 0.92-0.94 | 0.94-0.98 | 0.92 | ≈0.65 |
Breakdown Voltage KV/mm (20oC) | 70 | 85 | 50 | 30 |
Specific Volume Resistivity Ω cm (20oC) | 1017 | 1017 | 1012-1016 | 1017 |
Dielectric Constant 50 Hz (20oC) | 2.3 | 2.3 | 4-6 | ≈1.55 |
Dielectric Loss Factor (tan δ) | 2 x 10-4 | 3 x 10-4 | 2x 10-3 | 5 x 10-4 |
Working Temperature | Permanent oC | -50 +70 | -50 +00 | -35 +90 | -40 +70 |
Short Time oC | +100 | +120 | +100 | +100 |
Melt Temperature +oC | 105-110 | 130 | - | 105 |
Flame Resistance | Flammable | Flammable | Flammable | Flammable |
Oxygen Index LOI (% O2) | ≤22 | ≤22 | ≤22 | 18-30 |
Heating Value H0 MJ.kg-1 | 42-44 | 42-44 | 42-44 | 42-44 |
Thermal Conductivity W.K-1.m-1 | 0.3 | 0.4 | 0.3 | 0.25 |
Corrosive Gases In Case Of Fire | No | No | No | No |
Radiation Resistance max Mrad | 100 | 100 | 100 | 100 |
Tensile Strength N/mm2 | 10-20 | 20-30 | 12.5-20 | 8-12 |
Elongation At Break % | 400-600 | 500-1000 | 300-400 | 350-450 |
Shore Hardness | 43-50 (D) | 60-63 (D) | 40-45 (D) | - |
Abrasion Resistance | Medium | Good | Medium | - |
Water Absorption % | 0.1 | 0.1 | 0.1 | - |
Halogen Free | Yes | Yes | Yes | Conditional |
Weather Resistance | Medium (Black: Good) | Medium (Black: Good) | Good | - |
Cold Resistance | Good | Good | Good | Good |
Insulation Materials (other)
| 3Y | 4Y | 9Y | 11Y | TPE-E (12Y) | TPE-O |
PS | PA | PP | PUR | | |
Polystrole | Polyamide | Poly-propylene | Poly-urethane | PolYester Elastomer | Polyolefine Elastomer |
Density g/cm3 | 1.05 | 1.02-1.1 | 0.91 | 1.15-1.2 | 1.2-1.4 | 0.89-1.0 |
Breakdown Voltage KV/mm (20oC) | 30 | 30 | 75 | 20 | 40 | 30 |
Specific Volume Resistivity Ω cm (20oC) | 1016 | 1015 | 1016 | 1010-1012 | >1010 | >1014 |
Dielectric Constant 50 Hz (20oC) | 2.5 | 4 | 2.3-2.4 | 4-7 | 3.7-5.1 | 2.7-3.6 |
Dielectric Loss Factor (tan δ) | 1 x 10-4 | 2 x 10-2 to 1 x 10-3 | 4 x 10-4 | 2.3 x 10-2 | 1.8 x 10-2 | 1.8 x 10-2 |
Working Temperature | Permanent oC | -50 +80 | -60 +05 | -10 +100 | -55 +80 | -50 +100 | -50 +100 |
Short Time oC | +100 | +125 | +140 | +100 | +140 | +130 |
Melt Temperature +oC | >120 | 210 | 160 | 150 | 190 | 150 |
Flame Resistance | Flammable | Flammable | Flammable | Flammable | Flammable | Flammable |
Oxygen Index LOI (% O2) | ≤22 | ≤22 | ≤22 | ≤22 | ≤29 | ≤25 |
Heating Value H0 MJ.kg-1 | 40-43 | 27-31 | 42-44 | 20-26 | 20-25 | 23-28 |
Thermal Conductivity W.K-1.m-1 | 0.25 | 0.23 | 0.19 | 0.25 | 0.5 | 1.5 |
Corrosive Gases In Case Of Fire | No | No | No | No | No | No |
Radiation Resistance max Mrad | 80 | 10 | 10 | 100 | 10 | 10 |
Tensile Strength N/mm2 | 55-65 | 50-60 | 20-35 | 30-45 | 30 | 20 |
Elongation At Break % | 300-400 | 50-170 | 300 | 500-700 | >300 | >300 |
Shore Hardness | 35-50 (D) | - | 55-60 (D) | 70-100 (A) | 85 (A), 70 (D) | 55 (A), 70 (D) |
Abrasion Resistance | Good | Very Good | Medium | Very Good | Good | Good |
Water Absorption % | 0.4 | 1.0-1.5 | 0.1 | 1.5 | 1.5 | 1.5 |
Halogen Free | Yes | Yes | Yes | Yes | Yes | Yes |
Weather Resistance | Medium - Good | Good | Moderate | Very Good | Very Good | Very Good |
Cold Resistance | Moderate - Good | Good | Good | Very Good | Very Good | Very Good |
Elastomere Materials
| G | 2G | 3G | 4G | 5G | 6G |
NR SBR | SiR | EPR | EVA | CR | CSM |
Natural Rubber Styrol- Butadiene Rubber Compounds | Silicone Rubber | Ethylen- Propylene Rubber Compounds | Ethylene- Vinylacetate Copolymere Compounds | Poly- Chloroprene Compounds | Chloro- Sulfonated Polyethylene Compounds |
Density g/cm3 | 1.5-1.7 | 1.2-1.3 | 1.3-1.55 | 1.3-1.5 | 1.4-1.65 | 1.3-1.6 |
Breakdown Voltage KV/mm (20oC) | 20 | 20 | 20 | 30 | 20 | 25 |
Specific Volume Resistivity Ω cm (20oC) | 1012-1015 | 1015 | 1014 | 1012 | 1010 | 1012 |
Dielectric Constant 50 Hz (20oC) | 3-5 | 3-4 | 3-3.8 | 5-6.5 | 6-8.5 | 6-9 |
Dielectric Loss Factor (tan δ) | 1.9 x 10-2 | 6x 10-3 | 3.4 x 10-3 | 2 x 10-2 | 5 x 10-2 | 2.8 x 10-2 |
Working Temperature | Permanent oC | -65 +60 | -60 +180 | -30 +90 | -30 +125 | -40 +100 | -30 +80 |
Short Time oC | +120 | +260 | +160 | +200 | +140 | +140 |
Melt Temperature +oC | - | - | - | - | - | +160 |
Flame Resistance | Flammable | High Flash Point | Flammable | Flammable | Self Extinguishing | Self Extinguishing |
Oxygen Index LOI (% O2) | ≤22 | 25-35 | ≤22 | ≤22 | 30-35 | 30-35 |
Heating Value H0 MJ.kg-1 | 21-25 | 17-19 | 21-25 | 19-23 | 14-19 | 19-23 |
Thermal Conductivity W.K-1.m-1 | - | 0.22 | - | - | - | - |
Corrosive Gases In Case Of Fire | No | No | No | No | Hydrogen Chloride | Hydrogen Chloride |
Radiation Resistance max Mrad | 100 | 50 | 200 | 100 | 50 | 50 |
Tensile Strength N/mm2 | 5-10 | 5-10 | 5-10 | 8-12 | 10-20 | 10-20 |
Elongation At Break % | 300-600 | 300-600 | 200-400 | 250-350 | 400-700 | 350-600 |
Shore Hardness | 60-70 (A) | 40-80 (A) | 65-85 (A) | 70-80 (A) | 55-70 (A) | 60-70 (A) |
Abrasion Resistance | Moderate | Moderate | Moderate | Moderate | Medium | Medium |
Water Absorption % | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.5 |
Halogen Free | No | Yes | Yes | Yes | No | No |
Weather Resistance | Moderate | Good | Very Good | Good | Very Good | Very Good |
Cold Resistance | Very Good | Very Good | Good | Good | Moderate | Moderate |
High Temperature Materials
| 10Y | 7Y | 6Y | 5YX | 5Y |
PVDF | ETFE | FEP | PFA | PTFE |
Polyvinylidene Fluoride Kynar/Dyflor | Ethylene- Tetrafluorethylene | Fluorine Ethylene Propylene | Perfluoral- Koxypolymeric | Poly- Tetrafluorethylene |
Density g/cm3 | 1.7-1.9 | 1.6-1.8 | 2.0-2.3 | 2.0-2.3 | 2.0-2.3 |
Breakdown Voltage KV/mm (20oC) | 25 | 36 | 25 | 25 | 20 |
Specific Volume Resistivity Ω cm (20oC) | 1014 | 1016 | 1018 | 1018 | 1018 |
Dielectric Constant 50 Hz (20oC) | 9-7 | 2.6 | 2.1 | 2.1 | 2.1 |
Dielectric Loss Factor (tan δ) | 1.4 x 10-2 | 8 x 10-4 | 3 x 10-4 | 3 x 10-4 | 3 x 10-4 |
Working Temperature | Permanent oC | -40 +135 | -100 +150 | -100 +205 | -190 +260 | -190 +260 |
Short Time oC | +160 | +180 | +230 | +280 | +300 |
Melt Temperature +oC | >170 | >265 | >225 | >290 | >325 |
Flame Resistance | Self Extinguishing | Self Extinguishing | Self Extinguishing | Self Extinguishing | Self Extinguishing |
Oxygen Index LOI (% O2) | 40-45 | 30-35 | >95 | >95 | >95 |
Heating Value H0 MJ.kg-1 | 15 | 14 | 5 | 5 | 5 |
Thermal Conductivity W.K-1.m-1 | 0.17 | 0.24 | 0.26 | 0.21 | 0.26 |
Corrosive Gases In Case Of Fire | Hydrofluoric | Yes | Yes | Yes | Yes |
Radiation Resistance max Mrad | 10 | 10 | 1 | 0.1 | 0.1 |
Tensile Strength N/mm2 | 50-80 | 40-50 | 15-25 | 25-30 | 80 |
Elongation At Break % | 150 | 150 | 250 | 250 | 50 |
Shore Hardness | 75-80 (D) | 70-75 (D) | 55-60 (D) | 55-60 (D) | 55-60 (D) |
Abrasion Resistance | Very Good | Very Good | Very Good | Very Good | Very Good |
Water Absorption % | 0.01 | 0.02 | 0.01 | 0.01 | 0.01 |
Halogen Free | No | No | No | No | No |
Weather Resistance | Very Good | Very Good | Very Good | Very Good | Very Good |
Cold Resistance | Very Good | Very Good | Very Good | Very Good | Very Good |
Halogen Free Compounds
| H | HX |
Not Cross Linked | Cross Linked |
Halogen Free Polymer Compounds | Halogen Free Polymer Compounds |
Density g/cm3 | 1.4-1.6 | 1.4-1.6 |
Breakdown Voltage KV/mm (20oC) | 25 | 25 |
Specific Volume Resistivity Ω cm (20oC) | 1012-1014 | 1013-1014 |
Dielectric Constant 50 Hz (20oC) | 3.4-5 | 3.4-5 |
Dielectric Loss Factor (tan δ) | ~10-3 | 10-2-10-3 |
Working Temperature | Permanent oC | -30 +70 | -30 +90 |
Short Time oC | +100 | +150 |
Melt Temperature +oC | >130 | - |
Flame Resistance | Self Extinguishing | Self Extinguishing |
Oxygen Index LOI (% O2) | ≤40 | ≤40 |
Heating Value H0 MJ.kg-1 | 17-22 | 16-25 |
Thermal Conductivity W.K-1.m-1 | 0.17 | 0.20 |
Corrosive Gases In Case Of Fire | No | No |
Radiation Resistance max Mrad | 100 | 200 |
Tensile Strength N/mm2 | 8-13 | 8-13 |
Elongation At Break % | 150-250 | 150-250 |
Shore Hardness | 65-95 (A) | 65-95 (A) |
Abrasion Resistance | Medium | Medium |
Water Absorption % | 0.2-1.5 | 0.2-1.5 |
Halogen Free | Yes | Yes |
Weather Resistance | Medium in Black: Good | Medium in Black: Good |
Cold Resistance | Average | Average |
See Also
Thermoplastic and Thermosetting - myElectrical note comparing these types of insulation