High Voltage Transmission Cable
High Voltage and Extra High Voltage XLPE Insulated Cables for Transmission Grid, Substation Links and Urban Underground Networks
Voltage Range: 36/63kV – 290/500kV | IEC 60840 · IEC 62067 Certified | BS 7835 Available for GCC Projects | Single-Core & Three-Core Constructions | Lead Sheath / Copper Screen / HDPE Sheath | Type-Test Documentation Available
High Voltage Transmission Line’s overall structure from the inside to the outside of the components includes: conductor, insulation, inner sheath, filler (armored), outer insulation, the voltage level of 35 kilovolts or more, but more than 220 kilovolts can be regarded as ultra-high-voltage cables as well as ultra-high-voltage and so on.
Choose Your Voltage Level
As a professional high voltage cable manufacturer, ZMS electrical power company brand has been synonymous with the longest life in medium and high voltage cable systems. No matter in design or manufacturing, we can provide reliable performance and lower maintenance costs to ensure the stable operation of your current and future long-term power transmission projects.
They are suitable for installation outdoors, underground, and in water. And then they are also suitable for installation in power stations, wind power stations, industrial, subsea power transmission, etc.
High Voltage Cable – 36kV to 72.5kV
Single and three-core XLPE insulated power cables for primary transmission and substation interconnections at 36/63kV and 64/110kV. Available with copper wire shield and HDPE outer sheath, suitable for underground, tunnel, and duct installation.
Voltage: 36/63kV (Um=72.5kV)
Conductor: Copper or aluminum, ≤1600mm²
Insulation: XLPE (cross-linked polyethylene)
Shielding: Copper wire shielding
Outer sheath: PE or HDPE
Standard: IEC 60840 / BS 7835
Applications: Substation main feeders, urban power transmission and distribution, industrial park main power supply
High Voltage Cable – 110kV to 132kV
XLPE insulated high voltage cables for bulk power transmission and major substation connections at 110kV and 132kV. Single-core construction standard, with lead sheath option for water-blocking in wet or submarine applications. Type-tested to IEC 60840.
Voltage: 64/110kV – 76/132kV (Um=123kV–145kV)
Conductor: Copper or aluminum, below 2500mm²
Insulation: XLPE
Metallic Shielding/Sheath: Copper wire shielding or lead sheath (for waterproofing requirements)
Outer Sheath: HDPE
Standard: IEC 60840 / BS 7835 / IEC 60502 (extended to HV)
Applications: Urban power transmission main lines, industrial transformer feeders, large power plant outgoing lines
Extra High Voltage Cable – 220kV to 275kV
Extra high voltage single-core XLPE cables for main grid transmission at 220kV and 275kV. Longitudinally water-blocked with a metallic moisture barrier, HDPE outer sheath. Designed for high-capacity urban underground transmission routes where overhead lines are restricted.
Voltage: 127/220kV – 160/275kV (Um=245kV–300kV)
Conductor: Copper, below 2500mm²
Insulation: XLPE (high-quality cross-linked material)
Metallic Shielding: Copper wire shielding + longitudinal waterproofing
Outer Sheath: HDPE (PE-HD)
Standard: IEC 62067
Applications: Underground power transmission channels in large cities, cross-river and cross-sea cables, power plant transmission lines
Ultra High Voltage Cable – 330kV to 500kV
High-capacity single-core XLPE cables for backbone national grid transmission at 330kV, 400kV, and 500kV. Advanced longitudinal and radial water-blocking with lead alloy sheath or metallic tape laminate. Type-tested to IEC 62067 with full CIGRÉ qualification documentation available.
Voltage: 190/330kV – 290/500kV (Um=362kV–550kV)
Conductor: Copper, 2500mm² (customizable to 3200mm²)
Insulation: Ultra-clean XLPE
Metallic Sheath: Lead alloy sheath (longitudinal + radial water-blocking)
Outer Sheath: PE (black, UV stabilized)
Standard: IEC 62067 / CIGRÉ Technical Brochure
Applications: National backbone power grids, underground power transmission in megacities, submarine EHV inter-island connections
HV & EHV XLPE Cable Specifications
The following table provides reference specifications for standard single-core HV and EHV XLPE cables. Three-core constructions are available for voltages up to 132kV. All data is approximate — contact us with your specific project requirements for detailed technical drawings and calculations.
Voltage Level (Uo/U kV) | Highest Voltage Um (kV) | Conductor Cross-Sectional Area Range(mm²) | Outer Diameter Reference (mm) | Weight Reference (kg/m) | Metal Casing | Applicable Standards |
36/63kV | 72.5kV | 240–1,600 | 75–130 | 8–30 kg/m | Copper wire shielding | IEC 60840 / BS 7835 |
64/110kV | 123kV | 400–2,500 | 95–155 | 12–42 kg/m | Copper wire shielding | IEC 60840 / BS 7835 |
76/132kV | 145kV | 400–2,500 | 100–160 | 13–45 kg/m | Copper wire shielding or lead sleeve | IEC 60840 / BS 7835 |
127/220kV | 245kV | 630–2,500 | 120–175 | 18–55 kg/m | Lead sleeve or metal film | IEC 62067 |
160/275kV | 300kV | 800–2,500 | 135–185 | 22–62 kg/m | Lead alloy sleeve | IEC 62067 |
190/330kV | 362kV | 1,000–2,500 | 145–195 | 28–70 kg/m | Lead alloy sleeve | IEC 62067 |
290/500kV | 550kV | 1,600–2,500 | 170–215 | 40–85 kg/m | Lead alloy sleeve | IEC 62067 |
Note: The above data are standard reference values. Actual parameters are subject to ZMS technical drawings and factory inspection reports. The three-core structure can be used for 36kV–132kV, and its weight is 3 times the weight of a single core plus armor and outer sheath.
HV XLPE Cable Construction
ZMS HV and EHV XLPE cables are constructed in accordance with IEC 60840 and IEC 62067 requirements. The following table describes each layer from conductor to outer sheath:
Hierarchy (from inside to outside) | Material | Technical Specifications |
Conductor | Compacted stranded copper or aluminum (IEC 60228 Class 2) | Large cross-sections utilize milliken stranding to reduce AC resistance. Smooth conductor surfaces prevent abrupt changes in the electric field. |
Conductor Screen | Extruded semiconductive crosslinked material | Eliminates electric field inhomogeneities at the conductor surface and insulation interface. Co-extrusion with the insulation three layers ensures a clean and contamination-free interface. |
XLPE Insulation | Ultra-clean cross-linked polyethylene (XLPE) | Operating temperature 90°C, short-circuit temperature 250°C. Ultra-clean material (impurity particles <0.1mm) ensures reliable insulation under high voltage. |
Insulation Screen | Extruded semiconductive crosslinked material | It is co-extruded with the insulating three layers, and there is no air gap between the semiconductive layer and the insulating layer to prevent partial discharge. |
Longitudinal Water Barrier | Bentonite waterproof tape | IEC 60840/62067 requires that bentonite expands upon contact with water, preventing moisture from penetrating longitudinally along the cable. |
Metallic Sheath/Screen | Copper wire shielding (≤132kV) Lead alloy sleeve (≥220kV) | The copper wire shielding provides a grounding loop and a short-circuit current path. The lead alloy sheath also provides radial waterproofing (preventing water from seeping into the insulation from the outside). |
Outer Sheath | Black HDPE or PE | Mechanical protection, UV radiation resistance, and chemical corrosion resistance. Color-coded outer sheaths are typically required for tunnel and underground installations. |
Installation Methods for HV Underground Cables
Direct Burial: Suitable for 36kV–110kV, three single-core cables laid in a triangular or parallel configuration. Requires sand cushioning and concrete cover protection. Current carrying capacity is affected by soil thermal resistance, typically requiring thermal resistance testing.
Dual-Directional Installation: The most common urban HV cable installation method. HDPE conduits are pre-embedded, and expansion cement is injected after the cable is inserted. Cables are replaceable, facilitating maintenance.
Tunnel/Cable Gallery: Suitable for 220kV and above, multi-circuit, large-section cables. Requires a forced ventilation cooling system and offers higher current carrying capacity. Preferred method for ultra-high voltage transmission in urban core areas.
Horizontal Directional Drilling: Used for crossing obstacles such as rivers, roads, and railways. Cables are inserted into pre-drilled HDPE conduits; suitable for all voltage levels.
Engineering Consulting Support: The ZMS technical team can provide current carrying capacity calculations and cable cross-section selection suggestions based on your routing conditions (soil thermal resistance, installation method, ambient temperature, and the impact of multiple loops). Please provide a routing diagram and installation condition description when requesting a quote.
HV & EHV Cable Applications
Urban Underground Transmission
Substation Connections & Grid Links
Renewable Energy Grid Connection
Industrial & Power Plant Applications
High Voltage Cable Catalog
ZMS HIGH VOLTAGE CABLE PDF
ZMS provides our partners around the world with brochures of our cable products, including aerial cables, submarine cables, control cables and other types of special cables, and more.
ZMS Cable Factory also manufactures accessories and connectors related to high voltage cable splicing and high voltage cable clamp. If you don’t know how to choose the product you need or can’t find the cable type and size you need on this page, don’t worry. Contact us and send us your requirements, and we can help you choose the right cable. You can provide us with the following information: cable voltage, conductor material, insulation and sheath material, shield type, armor type, etc. or you can provide us with cable installation environment, application requirements, etc. We will serve you wholeheartedly. ZMS cable supplier has several quality certifications: ISO 9000, ISO 9001, ISO14000, ISO14001, ISO18000, CE, IEC, BS, NFC, ASTM, DIN, etc.
Partnering with ZMS
ZMS has provided customized high voltage cable services for Thailand, model no: Underground power cable, rated voltage 115 kV,single-core, with copper conductor, XLPE insulation,copper wire screen,PE sheath, conductor size 300 mm2
ZMS has provided customized high voltage cable services to Singapore, model no: 132KV 1C*630 Sqmm UG Cu.Ar Cable. The production cycle was completed in just 45 days, and the warranty is guaranteed for 18 months.
ZMS Cables has long been a specialist in the production of shielded high voltage cables.ZMS cable production sets an example for the industry with unrivaled quality and precision. Every cable produced by ZMS is made with attention to detail to ensure optimum performance and reliability. We also have extensive experience in customizing cables, including ultra-high voltage cables from 66 kV to 500 kV, etc. This is a must-have advantage as a specialized supplier of high voltage cables.