IEC 62873-3-3:2016(E) applies to RCDs equipped with screw-type terminals of copper - or of alloys containing at least 58 % of copper (if worked cold) or at least 50 % of copper (if worked otherwise), or of other metal or suitably coated metal, no less resistant to corrosion than copper and having mechanical properties no less suitable - for use with untreated aluminium conductors, or with screw-type terminals of aluminium material for use with copper or aluminium conductors.