NA2XS(FL)2Y 12/20 (24)kV MV Cable

What is NA2XS(FL)2Y 12/20 (24)kV Cable?

The NA2XS(FL)2Y 12/20 (24)kV Cable is a single-core aluminium conductor medium-voltage power distribution cable engineered according to IEC 60502-2, HD 620, and DIN VDE 0276-620 standards. It is specifically designed for 20kV electrical utility networks, primary sub-transmission circuits, and renewable generation collector lines where complete protection against both radial moisture diffusion and longitudinal water travel is required.

The standard German DIN VDE designation defines each structural element: NA indicates an aluminium conductor manufactured to IEC 60228 Class 2; 2X specifies Cross-Linked Polyethylene (XLPE) insulation; S represents a concentric metallic screen composed of copper wires and equalizing copper tape; (FL) designates dual waterblocking protection featuring longitudinal swellable tapes (F) combined with a laminated radial Aluminium/Polyester barrier tape (L) bonded to the sheath; and 2Y denotes a Medium Density Polyethylene (MDPE) outer jacket. This integrated design delivers AD8 submersion water resistance, AG2 impact endurance, and ISO 4892-3 UV stability for harsh direct-burial utility environments.

NA2XS(FL)2Y 12/20 (24)kV Cable Construction

• Conductor: Class 2 stranded compacted circular aluminium conductor conforming to IEC 60228.
• Conductor Screen: Extruded semi-conductive compound bonded directly over the conductor to eliminate electrical stress points.
• Insulation: Cross-Linked Polyethylene (XLPE) compound with a nominal thickness of 5.50mm, delivering dielectric strength and thermal endurance up to +90°C.
• Insulation Screen: Extruded semi-conductive compound bonded to the XLPE insulation layer for uniform radial electrostatic field distribution.
• Inner Longitudinal Waterblocking: Semi-conductive water-swellable tape applied beneath the copper screen to stop longitudinal moisture migration along the insulation interface.
• Screen: Concentric annealed copper wires overlaid with a helically bound copper tape to safely carry system fault currents.
• Outer Longitudinal Waterblocking: Non-conductive swellable tape wrapped over the metallic screen for secondary moisture containment.
• Radial Waterblocking: Aluminium/Polyester (Al/PET) copolymer-coated tape applied longitudinally and tightly bonded to the inner surface of the outer sheath to form an impermeable moisture barrier.
• Outer Sheath: Medium Density Polyethylene (MDPE) compound complying with EN 60229-4.1 for protection against abrasion, tear, and environmental cracking.
• Sheath Colour: Available in Red or Black.

Applications

NA2XS(FL)2Y 12/20 (24)kV cables provide power transmission across severe subterranean, wetland, and industrial environments:

• Public & Private Utility Distribution: Underground 20kV primary distribution circuits connecting municipal substations, switching stations, and step-down transformers.
• Direct Burial in Water-Logged Soils: Subsurface trench routing in wetlands, marshlands, and areas with permanently high water tables, leveraging bonded Al/PET radial and swellable longitudinal water barriers.
• Buried Cable Ducts & Tunnels: Installation inside concrete raceways, underground utility banks, and duct systems susceptible to seasonal or continuous flooding.
• Utility-Scale Solar & Wind Generation: Medium-voltage collector circuits routing electrical energy from wind turbine towers and central solar inverter pads to grid substations.
• Industrial & Petrochemical Complexes: Main power distribution lines for refineries, chemical manufacturing, and heavy industrial facilities requiring AG2 impact protection and chemical durability.

Specifications & Dimensions

Huadong Cable Group manufactures NA2XS(FL)2Y 12/20 (24)kV cables across single-core aluminium cross-sections from 50mm² up to 1200mm² (including 50, 70, 95, 120, 150, 185, 240, 300, 400, 500, 630, 800, 1000, and 1200mm²). Rated for 12/20 (24)kV with a 42kV AC 5-minute dielectric test voltage, the series features nominal overall outer diameters from 27mm (50mm²) up to 69.5mm (1200mm²) and unit weights spanning 750 kg/km to 5,780 kg/km. Nominal XLPE insulation thickness is standardized at 5.50mm (minimum 4.85mm), complemented by copper screen cross-sections of 16mm², 25mm², or 35mm² yielding short-circuit screen current capacities from 3.2kA to 7.1kA for 1 second. Continuous current carrying capacities reach up to 988A in ground (20°C), 907A in duct (30°C), and 1,274A in free air (30°C) for 1200mm² conductors under flat touching formation. Maximum pulling tension ratings range from 1,500 N up to 22,240 N, and maximum sidewall pressures reach 1,947 N/cm² under an installation bending radius of 15 times the overall diameter, fully conforming to IEC 60502-2 and VDE 0276-620 specifications.

Standards

Design & Material Standards: IEC 60502-2, HD 620, DIN VDE 0276-620, IEC 60228 Class 2
Waterblocking & Ingress Protection: Dual-barrier radial (bonded Al/PET tape) and longitudinal waterblocking (swellable tapes), Water resistant to AD8
Mechanical & Environmental Endurance: Abrasion and tear resistant to EN 60229-4.1, Impact rated to AG2 per EN 60364-5.51, UV resistant to ISO 4892-3
Halogen Content: Halogen-free according to IEC 60754
Electrical & Thermal Ratings: Voltage Rating Uo/U (Um): 12/20 (24)kV; Test Voltage: 42kV AC 50Hz (5 min); Conductor Max Temp: +90°C; Short Circuit Limit (5s): +250°C; Min Bending Radius: 15 × OD
Regulatory Compliance: RoHS Directive 2015/65/EU, REACH EC 1907/2006, CE Marked

Frequently Asked Questions

Q: What is the technical difference between NA2XS(F)2Y and NA2XS(FL)2Y cables?
A: The NA2XS(F)2Y cable features longitudinal waterblocking tapes only, whereas the NA2XS(FL)2Y incorporates an additional radial water barrier consisting of an Aluminium/Polyester (Al/PET) foil bonded directly to the MDPE jacket. This radial foil prevents radial water vapor diffusion into the XLPE insulation under saturated soil conditions.

Q: Why is an MDPE outer sheath chosen instead of standard PVC?
A: Medium Density Polyethylene (MDPE) provides superior mechanical toughness, puncture resistance, and tear strength (EN 60229-4.1), along with lower moisture permeability and long-term UV resistance according to ISO 4892-3.

Q: What is the benefit of using aluminium conductors over copper in 20kV distribution?
A: Class 2 stranded aluminium provides substantial capital savings and weight reduction across extended distribution feeders, reducing freight costs and installation pulling tensions while delivering stable electrical performance.

Q: What commercial payment terms does Huadong Cable accept for international projects?
A: We accept standard international commercial payment terms, primarily Telegraphic Transfer (T/T, with 30% advance deposit and 70% against shipping documents) and 100% Irrevocable Letter of Credit (L/C) at sight.

NA2XS(FL)2Y 12/20 (24)kV Cable – Why Choose Huadong Cable?

Huadong Cable Group manufactures NA2XS(FL)2Y 12/20 (24)kV medium-voltage cables in strict compliance with IEC 60502-2, HD 620, and DIN VDE 0276-620 specifications. Utilizing electrical-grade aluminium rod, our high-speed stranding equipment produces compacted circular Class 2 conductors that minimize overall cross-sectional diameter and surface roughness. In our triple-extrusion catenary continuous vulcanization (CCV) lines, the conductor screen, high-cleanliness XLPE insulation, and bonded insulation screen are co-extruded under pressurized dry nitrogen curing, ensuring void-free interfaces and negligible partial discharge levels. During the jacketing process, the copolymer-coated Al/PET laminate is bonded to the extruded MDPE outer sheath, creating a hermetic seal against radial water ingress.

Backed by more than 20 years of precision cable engineering expertise, Huadong Cable Group operates testing facilities accredited under ISO/IEC 17025 and certified to ISO 9001 and CE quality frameworks. Direct factory supply eliminates intermediary agent markups, allowing us to provide competitive factory pricing, 100% routine testing (including high-voltage AC withstand, dielectric loss, and partial discharge verification) documented via Mill Test Certificates (MTC), continuous drum cuts packaged on heavy-duty ISPM 15 heat-treated export wooden reels, and dependable logistics for international electric utilities and EPC contractors worldwide.