BS 7870-4.20:2011+A1:2016 specifies requirements for the construction, dimensions and mechanical and electrical properties of 6.35/11(12) kV three-core cables having either aluminium or copper conductors, cross-linked polyethylene (XLPE) or ethylene propylene rubber (EPR) extruded insulation, a copper wire metallic screen and an oversheath of one of the following compounds.

• medium density polyethylene (MDPE) compound type DMP 5 (Type A cables);
• thermoplastic compound type DMZ 4 for cables having a low emission of smoke and corrosive gases when affected by fire (Type B cables).

This section of BS 7870 is applicable to cables that are designed for a maximum continuous conductor operating temperature of 90 °C and for a maximum short-circuit conductor temperature of 250 °C.
NOTE Information to be supplied by the purchaser, and items to be agreed between the purchaser and the manufacturer at the time of enquiry and/or order are given in Annex B. Guidance on type testing is given in Annex C.

To be read in conjunction with BS 7870-1:2011,BS 7870-2:2011


Cross References:
BS 3988:1970+A3:1989
BS 7870-1
BS 7870-2
BS EN 50267-2-1
BS EN 60228:2005
BS EN 60332-1-2:2004
BS EN 60332-3-24:2009
BS EN 60811-1-2
BS EN 60811-1-3
BS EN 60811-2-1
BS EN 61034-1
BS EN 61034-2
HD 603 S1
HD 605 S2
HD 620 S2
HD 626 S1
HD 627 S1
IEC 60502-2


Incorporates the following:
Corrigendum, August 2012. Amendment, June 2016. Amends and replaces BS 7870-4 .20:2011