IEC 62420:2008 specifies the electrical and mechanical characteristics of concentric lay stranded overhead electrical conductors, containing one or more self-supporting alumimium or aluminium alloy layer(s) made of combination of any of the following metal wires:
- Hand drawn aluminium as per IEC 60889, designated A1,
- aluminium alloy type A or B as per IEC 60104, designated A2 or A3,
- thermal resistant aluminium alloy as per IEC 62004, designated AT1, AT2, AT3, or AT4,
- regular strength steel as per IEC 60888, designated S1A or S1B,
- high strength steel as per IEC 60888, designated S2A or S2B,
- extra-high strength steel as per IEC 60888, designated S3A,
- aluminium-clad steel as per IEC 61232, designated 20SA, 27SA, 30SA or 40SA.