1. Overview of Medium Voltage Power Cables

Medium voltage power cables are designed to operate within the voltage range of 6 kV to 35 kV, as defined by IEC 60038. They are used in applications requiring higher power transmission than LV cables (up to 1 kV) but shorter distances than HV cables (above 35 kV). MV cables are engineered with advanced insulation, shielding, and armoring to handle electrical stress, mechanical loads, and environmental challenges. They are essential in industries such as manufacturing, mining, oil and gas, and renewable energy. Henan Province Jianyun Cable Co., Ltd. provides TUV- and CCC-certified MV cables, ensuring reliability and compliance for global projects.

2. Construction of Medium Voltage Power Cables

MV power cables feature a complex construction to ensure safety, durability, and performance under high electrical stress:

• Conductor: Copper or aluminum, typically stranded (Class 2 per IEC 60228) for flexibility and high current capacity. Cross-sections range from 25 mm² to 400 mm².
• Conductor Screen: Semi-conductive layer to smooth electric fields and prevent stress concentrations.
• Insulation: Cross-linked polyethylene (XLPE) or ethylene propylene rubber (EPR) for high dielectric strength (≥20 kV/mm) and thermal resistance (90°C).
• Insulation Screen: Semi-conductive layer to control electric fields and ensure uniform insulation performance.
• Metallic Shield: Copper tape or wire to manage electric fields, provide grounding, and protect against partial discharge (<10 pC).
• Armoring: Steel wire armor (SWA) or steel tape for mechanical protection, especially in underground or high-impact environments.
• Outer Sheath: Polyvinyl chloride (PVC), polyethylene (PE), low-smoke zero-halogen (LSZH), or polyurethane (PUR) for environmental resistance.

Example: Jianyun Cable’s 11 kV XLPE-insulated, SWA-armored cable features a copper conductor, XLPE insulation, copper tape shield, and LSZH sheath for industrial applications.

3. Technical Specifications and Standards

MV power cables must meet stringent technical requirements to ensure safety and reliability:

• Conductor:
  • Material: Copper (≥99.9% purity) or aluminum.
  • Class 2 stranded per IEC 60228; resistance <4.61 Ω/km for 4 mm² copper to minimize voltage drop (<1.5%).
• Insulation:
  • XLPE or EPR; thickness 2.5–8 mm (e.g., 3.4 mm for 11 kV per IEC 60502-2).
  • Dielectric strength ≥20 kV/mm; partial discharge <10 pC.
• Shielding:
  • Copper tape or wire for electric field management and grounding.
• Sheathing and Armoring:
  • PVC, PE, LSZH, or PUR sheath; SWA or steel tape armoring for mechanical protection.
• Voltage Rating:
  • 6 kV to 35 kV (e.g., 6/10 kV, 8.7/15 kV, 12/20 kV, 18/30 kV).
• Standards:
  • IEC 60502-2: MV power cables (6–30 kV).
  • IEC 60038: Voltage classification.
  • IEC 60332-3: Flame-retardant properties for bundled cables.
  • IEC 60754-1/IEC 61034: LSZH requirements for low smoke and toxicity.
  • RoHS/REACH: Restrictions on hazardous substances.
• Certifications: Jianyun Cable provides TUV, CCC, and ISO 9001-certified MV cables, ensuring global compliance.

4. Applications of Medium Voltage Power Cables

MV power cables are used in a wide range of applications requiring reliable power transmission:

4.1. Industrial Facilities

• Powering heavy machinery (e.g., presses, motors) in manufacturing plants.
• Voltage: 6–15 kV; SWA-armored, XLPE-insulated cables.
• Example: Jianyun Cable’s 11 kV XLPE-insulated cable for factory distribution.

4.2. Mining Operations

• Supplying underground equipment (e.g., conveyors, pumps).
• Voltage: 6–15 kV; PUR-sheathed, armored cables for abrasion resistance.
• Example: Jianyun Cable’s 6 kV PUR-sheathed cable for mining.

4.3. Oil and Gas

• Powering offshore platforms, refineries, and pumps.
• Voltage: 11–33 kV; EPR-insulated, lead-sheathed cables for chemical resistance.
• Example: Jianyun Cable’s 33 kV EPR-insulated cable for offshore platforms.

4.4. Renewable Energy

• Connecting solar farms or wind turbines to the grid.
• Voltage: 11–35 kV; UV-resistant XLPE cables.
• Example: Jianyun Cable’s 35 kV XLPE-insulated cable for solar farms.

4.5. Infrastructure

• Powering airports, data centers, or industrial parks.
• Voltage: 5–15 kV; LSZH-sheathed cables for fire safety.
• Example: Jianyun Cable’s 5 kV LSZH-armored cable for airport lighting.

5. Selection Criteria for Medium Voltage Power Cables

Choosing the right MV power cable involves evaluating several factors:

• Electrical Requirements:
  • Calculate load (e.g., 200 A for industrial motors) and select conductor size (e.g., 50 mm² for 11 kV) per IEC 60364.
  • Match voltage rating to system (e.g., 12/20 kV for substations).
• Environmental Conditions:
  • Use LSZH cables for confined spaces (e.g., data centers) per IEC 60754-1.
  • Choose PUR or PE for chemical or moisture resistance in mining/oil environments.
  • Select UV-resistant XLPE for outdoor renewable energy projects.
• Installation Needs:
  • Use SWA-armored cables for underground or high-impact areas; maintain 6–10D bending radius.
  • Ensure proper jointing (e.g., heat-shrink kits) and termination for reliability.
• Safety and Compliance:
  • Verify compliance with IEC 60502-2 and regional standards (e.g., G-Mark for GCC markets).
  • Request TUV, UL, or CCC certifications via official databases (e.g., TUV Certipedia).
• Supplier Reliability:
  • Partner with manufacturers like Jianyun Cable, offering TUV-certified MV cables with proven performance (e.g., showcased at Elektro 2025 in Moscow).
  • Request batch-specific test reports (e.g., insulation resistance >1000 MΩ/km) and factory audits (e.g., SGS).

6. Challenges and Solutions

7. Conclusion

Medium voltage power cables (6–35 kV) are vital for efficient power transmission in industrial, utility, and infrastructure applications. Their robust construction, including stranded conductors, XLPE or EPR insulation, copper shielding, and SWA armoring, ensures durability and safety in demanding environments. Compliance with standards like IEC 60502-2, IEC 60038, and IEC 60332-3 guarantees performance and safety. Henan Province Jianyun Cable Co., Ltd. offers TUV- and CCC-certified MV cables, providing reliable solutions for manufacturing, mining, oil and gas, renewable energy, and infrastructure projects. By carefully evaluating electrical, environmental, and installation requirements, and partnering with trusted suppliers, users can ensure safe, efficient, and durable power distribution systems lasting 20–30 years.