XHE 49 (-A)

XLPE INSULATED POWER CABLES

CABLE TYPE (A)2XS(F)2Y (XLPE) 6-35 kV

DESCRIPTION
Single-core N2XS(F)2Y cable is being made in accordance with IEC 60502/98.
Copper or aluminium compacted stranded circular conductor, conductor screen of extruded layer of semi-conducting XLPE, XLPE insulation, insulation screen of extruded layer of semi conducting XLPE, semi-conducting swellable tape, metallic screen consisting of copper wires applied helically with a counterspiral of copper tape, non-conducting swellable tape with or without copolymer coated Al tape longitudinally applied and PE outersheath in black colour.

Minimum bending radius:

  cable during instalation

cable placed in position adjacent to joints or terminations

NON-ARMOURED

20D

15D

ARMOURED

20D

12D

D - outer cable diameter

Current carrying capacity has been calculated according to IEC 287/82 (100 % load factor) and following conditions:

  • Depth of laying 0.70 m, and for 20/35 kV cables 1.0 m.
  • Soil thermal resistivity 1.0 K m/W.
  • Ground temperature 20oC, ambient air temperature 30oC, maximum conductor operating temperature 90oC.

Type of laying :

  • three cables in trefoil
  • three cables in flat
  • sheaths bonded at both ends of an electrical section

RATING FACTORS

 

Ambient temperature oC

15

20

25

30

35

40

Factor

Cable in ground

1.04

1.00

0.96

0.93

0.89

0.85

Cable in air

1.14

1.09

1.05

1.00

0.95

0.90


 

Soil thermal resistivity (Km/W)

Factor

0.7

1.0

1.2

1.5

2.0

2.5

3.0

1.12

1.00

0.94

0.86

0.77

0.71

0.66

COMPARISON OF CHARACTERISTIC VALUES OF INSULATING COMPAUNDS

  Type of insulating compaunds

UPET

PET

PVC

Maximum continous conductor operating temperature oC

90

70

65

Maximum conductor short-circuit temperature oC

250

150

160

Dielectric power factor at 50Hz, 20oC

4 x 10-4

2 x 10 -4

10-2

Relative permittivity at 50Hz, 20oC

2.3

2.3

4-8

Volume resistivity at 20oC ohm.cm

1017

1017

1014

Thermal resistivity K.m/W

3.5

3.5

6.0

Tensile strenth, minimum N/cm2

200

150

250

Elongation-at-break, minimum %

350

550

250