What is BS 7870-4.20 - LV and MV polymeric insulated cables about?
BS 7870-4.20 is a British Standard that discusses LV and MV polymeric insulated cables for use by distribution and generation utilities.
BS 7870-4.20 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 overheat 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 low emission of smoke and corrosive gases when affected by fire (Type B cables)
BS 7870-4.20 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.
Who is BS 7870-4.20- LV and MV polymeric insulated cables for?
BS 7870-4.20 on polymeric insulated cables is relevant to:
- Manufacturers of polymeric insulated cables
- Power generation and distribution companies
- Product design engineers
- Local authorities
- Quality control and testing agencies
- Electrical engineers
Why should you use BS 7870-4.20 – LV and MV polymeric insulated cables?
BS 7870-4.20 provides guidance on construction and dimensions, and recommends various routine tests, sample tests, and type tests that can demonstrate the quality and performance of polymeric insulated cables. If you are a manufacturer, you can thus determine whether or not your products are fit for purpose.
Establishing conformity to these tests and requirements, you can ensure your polymeric insulated cables play a positive role in the performance of the end-use applications. As a result, concerns of voltage stress, shrinkage, poor insulation, and overall product failure can be minimized.
