BS 7870-4.20:1999

Committees responsible
Foreword
1. Scope
2. Normative references
3. Voltage designation
4. Construction and dimensions
5. Test requirements
6. Routine tests
7. Sample tests
8. Type tests
Annex A (informative) User options for three-core
    polymeric insulated cables having a rated voltage of
    6.35/11 kV
Annex B (informative) Guidance on type tests
Bibliography
Table 1 - Dimensions of shaped solid aluminium conductors
Table 2 - Three-core cable with shaped solid aluminium
   conductors and copper wire collective metallic screen
Table 3 - Three-core cable with shaped stranded aluminium
   conductors and copper wire collective metallic screen
Table 4 - Three-core cable with circular solid aluminium
   conductors and copper wire collective metallic screen
Table 5 - Three-core cable with circular stranded
   aluminium conductors and copper wire collective
   metallic screen
Table 6 - Three-core cable with shaped solid aluminium
   conductors and galvanized steel wire armour
Table 7 - Three-core cable with shaped stranded aluminium
   conductors and galvanized steel wire armour
Table 8 - Three-core cable with circular solid aluminium
   conductors and galvanized steel wire armour
Table 9 - Three-core cable with circular stranded
   aluminium conductors and galvanized steel wire armour
Table 10 - Schedule of tests
Table 11 - D.C. resistance of copper wire screen
Table 12 - Cross-linked polyethylene (XLPE) and ethylene
   propylene rubber compound (EPR) insulation
Table 13 - Mass of zinc coating
Table 14 - Medium density polyethylene (MDPE) oversheath
Table 15 - Compatibility requirements
Table 16 - Tan delta in relation to voltage
Table 17 - Tan delta in relation to temperature
Table A.1 - Options to be specified by the user

Specifies the construction and dimensions of 6.35/11(12) kV three- core cables comprising conductors of aluminium, extruded insulation of crosslinked polyethylene or ethylene propylene rubber, a collective metallic screen of copper or steel wire, and an oversheath of medium-density polyethylene. The cables can be laid directly in the ground, in ducts or in air, for operation at a continuous maximum conductor temperature of 90 degC and a maximum conductor short-circuit temperature of 250 degC. Annexes summarize user options and give guidance on type testing. A long-term test is included for assessing performance in wet conditions.