This part of IEC 60999 applies to screw-type and screwless-type clamping units for connecting devices, either as separate entities or as integral parts of equipment, for the connection of electrical copper conductors (complying with IEC 60228), rigid stranded and/or flexible, having a cross-section above 35 mm2 and up to and including 300 mm2 and equivalent AWG/kcmil sizes with a rated voltage not exceeding 1 000 V a.c. and a frequency up to and including 1 000 Hz and 1 500 V d.c.

It applies to clamping units primarily suitable for connecting unprepared conductors.

This standard does not apply to clamping units:

- for connection by crimping or soldering;

- for non-universal clamping units defined in 3.10.2 of IEC 60999-1.