Medium Voltage Cables | |||
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 |
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))