Medium Voltage Cables
Medium Voltage Cables to BS 6622 Medium Voltage Cables to IEC 60502 Medium Voltage Cables to VDE 0276

Medium Voltage Cables to VDE 0276

Three Core Cables to VDE 0276

Application

The three core cables are designed for distribution of electrical power with nominal voltage Uo/U ranging from 3.6/6.6KV to 19/33KV and frequency 50Hz. They are suitable for installation mostly in power supply stations, indoors and in cable ducts, outdoors, underground and in water as well as for installation on cable trays for industries, switchboards and power stations.

Standards

DIN VDE 0276 Part 620 -622
HD 620 S1

Construction

Conductor:

Stranded compacted circular copper or aluminium conductors according to IEC 60228 class 2 / VDE 0276 class 2. VDE 0295 HD 383. All internal interstices of the conductor are filled with water blocking compound to prevent ingress of water through conductor during storage, handing, installation and operating of the cable.

Conductor Screen:

The conductor screen consists of an extruded layer of non metallic, semi-conducting compound firmly bonded to the insulation to exclude all air voids. The screen has a minimum thickness of 0.3mm and the maximum volume resistivity of 500 Ohm-m at 90°C.

Insulation:

Insulation is of extruded XLPE compound type 2XI1 according to DIN VDE 0207 part 22 and HD 620.1 with high degree of cross-linking, free from contaminants, air voids and heat resistant by dry cured process.
The nominal insulation wall thickness is shown in table 1.
Table 1. Insulation Thickness

Nom. Cross-Section
Area
Insulation Thickness at Nom. Voltage
3.6/6kV (Um=7.2)kV 6/10KV (Um=12KV) 8.7/15KV (Um=17KV) 12/20KV (Um=24KV) 18/30KV (Um=36KV)
mm² mm mm mm mm mm
  XLPE XLPE XLPE XLPE XLPE
35 2.5 3.4 4.5 5.5 -
50 2.5 3.4 4.5 5.5 8.0
70 2.5 3.4 4.5 5.5 8.0
95 2.5 3.4 4.5 5.5 8.0
120 2.5 3.4 4.5 5.5 8.0
150 2.5 3.4 4.5 5.5 8.0
185 2.5 3.4 4.5 5.5 8.0
240 2.6 3.4 4.5 5.5 8.0
300 2.8 3.4 4.5 5.5 8.0
400 3.0 3.4 4.5 5.5 8.0

Insulation Screen:

The insulation screen consists of extruded non metallic, semi-conducting compound extruded over the insulation. The extruded semi-conducting layer shall consist of bonded or cold strippable semi-conducting compound capable of removal for jointing or terminating. The minimum thickness is 0.3mm and the maximum volume resistivity of 500 Ohm-m at 90°C. The screen is tightly fitted to the insulation to exclude all air voids and can be easily hand stripped on site.

Conducting Water Blocking Layer:

The insulation screen may be covered by semi- conductive water blocking tape which will swell up under the influence of moisture of water to ensure longitudinal watertightness.

Metallic Screen:

Copper wires are applied over the conducting water blocking layer with a minimum diameter of 0.5mm. And over the copper wires, copper tape with minimum thickness of 0.1mm is applied helically with overlap. Total cross section of metallic screen layer is shown in table 2. The screen can withstand of fault current to earth of 1000 A for one second at maximum temperature of 160°C. Minimum cross section of concentric conductor is according to DIN VDE 0273 & 0276 as shown.
Table 2. Minimum Total Cross Section of Metallic Screen

Nominal Cross-Section Area Of Cable Minimum Cross-Section of Metallic Screen DC Resistance of the Copper Wire Screen
mm² mm² mm
Up to 120 16 1.06
150-300 25 0.72
400-630 35 0.51
800-1000 50 0.35

Separator / Water Blocking Layer:

The metallic screen may be covered by non-conducting water blocking tape which will swell up under the influence of moisture of water to ensure longitudinal watertightness.

Separation Sheath (for armoured cable):

The separation sheath comprises a layer of extruded PVC, PE or LSZH, applied under the armour. Thickness of separation sheath is shown in table 3.
Table 3. Separation Sheath Thickness

Cores Diameter Approx.Thickess of Inner Sheath
mm mm
>  <   
35 45 1.4
45 60 1.6
60 80 1.8
80 - 2.0

Armour(for armoured cable): The armour consists of:
1) Double layers of galvanized steel tape are applied helically with proper inner overlapping over an extruded separation sheath. Thickness of the steel tape is shown in table 4.
Tabel 4. Galvanized Steel Tape Thickness

Inner Diameter Thickness of Galvanized Steel Tape
mm mm
>  <   
- 30 0.2
30 70 0.5
70 - 0.8

2) Galvanized flat steel wires with thickness of 0.8 mm are applied helically over the surface of inner sheath with minimum of 90% coverage. And galvanized Steel tape with nominal thickness of 0.3 mm is applied helically with 50% coverage to cover the surface of the flat wires.

Outer Sheath:

Overall sheath comprises a layer of extruded PE compound DMP2 according to HD620.1 and 2YM3 type to DIN VDE 0276 Part 3, or PVC compound DMV6 according to HD620.1 and YM5 to DIN VDE 0276 Part 6. Normal wall thickness is 2.5mm (1/500mm
18/30sq 2.6mm), suitable for exposure to sun-light or other local atmospheric environments and for the operating temperature of the cable.

PHYSICAL PROPERTIES:

Operating Temperature: up to 90°C

Temperature Range: -5°C ( PVC sheath ); -20°C ( PE sheath )

Short Circuit Temperature: 250°C (short circuit duration up to 5 seconds)

Bending Radius: 15 x OD (Cable without metal sheath)
30 x OD (Cable with aluminium sheath)
Table 5. Nominal /Operating /Testing Voltages

Nominal Voltage Uo/U Operating Voltage (Um) Testing Voltage
3.6/6KV 8KV 12.5KV
6/10KV 12KV 21KV
8.7/15KV 18KV 30.5KV
12/20KV 24KV 42KV
18/30KV 36KV 63KV

Medium  Voltage Cables to VDE 0276

TYPE CODES:
Conductor

N          According to VDE Standard (No abbreviation for copper conductor) A  Aluminium conductor
Copper conductor

Insulation
2X       XLPE

Screen
C        Concentric conductor of copper
CE       Concentric conductor of copper over each individual core
S         Screen of copper wires & copper tape,helically wound
SE       Screen of copper wires over each individual cores
(G)      Longitudinally waterproof

Armour
F         Armour of galvanized flat steel wire
G        Counter Helix of galvanized steel tape
B         Steel tape armouring
R        Armour of galvanized round steel wire

Sheath
2Y        PE
Y           PVC H           LSZH
K         Lead sheath
KL       Aluminium sheath

Three Core  3.6/6KV (Um=7.2KV)
N2XSEY
NA2XSEY
Dimensional Data

Nom. Cross- Section Area Approx. Conductor Diameter Nom. Insulation Thickness Copper Tape Thickness Copper Wire Screen Area* Approx. Insulation Diameter Nom. Sheath Thickness Approx. Overall Diameter Approx. Weight
Cu Al
mm² mm mm mm mm² mm mm mm kg / km kg / km
25 6.05 2.5 0.1 16 12.5 1.5 37 2100 1600
35 7.10 2.5 0.1 16 13.5 1.6 39 2500 1800
50 8.25 2.5 0.1 16 14.7 1.6 42 3000 2100
70 9.90 2.5 0.1 16 16.3 1.7 46 3800 2500
95 11.7 2.5 0.1 16 18.1 1.7 50 4800 3000
120 13.1 2.5 0.1 16 19.5 1.8 53 5800 3500
150 14.3 2.5 0.1 25 20.7 1.8 56 6700 3900
185 16.3 2.5 0.1 25 22.7 1.9 60 8100 4600
240 18.7 2.6 0.1 25 25.3 1.9 66 10200 5600
300 20.9 2.8 0.1 25 27.9 2.0 72 12500 6700
400 23.7 3.0 0.1 35 31.1 2.1 80 15600 8200

*Optional wire screen can be provided in combination of copper tapes. Nominal screen area, as stated in the table, can be supplied as standard.

Three Core 3.6/6KV (Um=7.2KV) Galvanized Steel Tape Armoured Cables
N2XSEYBY NA2XSEYBY Dimensional Data

Nom. Cross- Section Area Approx. Conductor Diameter Nom. Insulation Thickness Copper Tape Thickness Copper Wire Screen Area* Approx. Insulation Diameter Nom. Armour Thickness Nom. Sheath Thickness Approx. Overall Diameter Approx. Weight
Cu Al
mm² mm mm mm mm² mm mm mm mm kg / km kg / km
25 6.05 2.5 0.1 16 12.5 0.5 2.2 39 2800 2300
35 7.10 2.5 0.1 16 13.5 0.5 2.3 42 3200 2600
50 8.25 2.5 0.1 16 14.7 0.5 2.4 45 3800 2900
70 9.90 2.5 0.1 16 16.3 0.5 2.5 49 4700 3400
95 11.7 2.5 0.1 16 18.1 0.5 2.6 53 5800 4000
120 13.1 2.5 0.1 16 19.5 0.5 2.7 56 6800 4600
150 14.3 2.5 0.1 25 20.7 0.5 2.8 59 7900 5100
185 16.3 2.5 0.1 25 22.7 0.8 2.9 64 9400 5900
240 18.7 2.6 0.1 25 25.3 0.8 3.1 70 11700 7000
300 20.9 2.8 0.1 25 27.9 0.8 3.3 76 14100 8300
400 23.7 3.0 0.1 35 31.1 0.8 3.6 85 18300 10900

*Optional wire screen can be provided in combination of copper tapes. Nominal screen area, as stated in the table, can be supplied as standard.

Three Core 3.6/6KV (Um=7.2KV) Galvanized Flat Steel wire+Steel Tape Armoured Cables
Three Core 6/10KV (Um=12KV)
Three Core  8.7/15KV (Um=17.5KV)
Three Core 12/20KV (Um=24KV)
Three Core 18/30KV (Um=36KV)
Current Rating for Three Core 1.8/3KV(Um=7.2 )KV to 26/35KV(Um=42KV)