12/20(24)kV CU XLPE PVC Un-armoured Cable

Application

Medium-voltage unarmoured cables (3.6/6kV ~ 18/30kV) are widely used in the following scenarios:

Suitable for AC 50 Hz power supply lines, such as urban underground power grids, outgoing lines of power stations and internal power networks of industrial and mining enterprises.

Industrial Facilities: Cable trays inside factory workshops and interconnection cables for power distribution rooms.

Large Public Buildings: incoming lines laid in cable trays / cable trenches in commercial complexes, data centers and hospital basements.

Transportation Hubs: Medium voltage power distribution circuits in utility tunnels and cable tunnels, wiring inside building cable shafts and transformer rooms.

Characteristics

Voltage Rating Uo/U (Um)
12/20(24)kV

Electrical Characteristics:
AC High voltage test: 3.5U0 for 5min
Partial Discharge at 1.73 U0: 10PC or better

Temperature Rating:
Maximum operating temperature of conductor: +90℃
Ambient temperature for service: -15℃ ～ +55℃
Conductor emergency operating temperature: 105℃
Conductor short-circuit operating temperature (5s): 250℃

Cable laying temperature:
Not lower than 0℃ (Preheat the cable if the ambient temperature is below 0℃).

Minimum Bending Radius During Laying
Single-core cable: 20D
Three-core cable: 15D
D refers to the actual outer diameter of the cable.

Laying Methods:
Conduit laying, trench laying, tunnel laying, shaft laying, cable tray laying, etc.

Products Construction

1.Conductor
Circular compacted copper conductor

2.Conductor Screen
Semi-conductive compound (for cross-section below 500mm²)
Semi-conductive tape+semi-conductive compound (for cross-section of 500mm² and above)

3.Insulation
Cross-linked polyethylene (XLPE)

4.Insulation Screen
Strippable semi-conductive compound

5.Metallic Screen
Copper tape
Copper wires

6.Filler
Non-hygroscopic filler ropes

7.Wrapping Tape
Non-hygroscopic binding tape

8.Outer Sheath
90℃ PVC (Non-fire-retardant type)
90℃ Fire-retardant PVC (Fire-retardant type)

Core Identification
Single-core: None
Three-core: Colour tape

Sheath Colour
Black or Red

Cable Drawing :

Applicable Standards

Optional

Technical Parameters

Dimensions

Electrical Characteristics

Single Core

Three Cores

Correction factors for ampacity

For single-core cables arranged in a trefoil formation, the cables are in contact with each other; when installed in ducts, the ducts are in contact with each other.

For single-core cables arranged in parallel with spacing, the axial distance between cables is 2 times the cable outer diameter.

For calculations under base conditions, the burial depth in soil is taken as 1.0 m, and the soil thermal resistivity is taken as 1.0 K·m/W.

Depending on the soil type, the corresponding soil conditions and meteorological conditions for different thermal resistivities are approximately as follows:

• 0.7: Soil condition: Very wet; Meteorological condition: Continuous rainfall
• 1.0: Soil condition: Wet; Meteorological condition: Normal rainfall
• 2.0: Soil condition: Dry; Meteorological condition: Infrequent rainfall
• 3.0: Soil condition: Very dry; Meteorological condition: Rare or no rainfall

The ducts are plastic pipes. (Assume the duct inner diameter is 1.5 times the cable outer diameter, and the duct wall thickness is 6% of the duct inner diameter.)

The metallic screen is not directly grounded at both ends.

FAQ