IEC 60309-1:2021 applies to plugs, fixed or portable socket-outlets and appliance inlets hereinafter referred to as accessories, with a rated operating voltage not exceeding 1 000 V DC or 1 000 V AC with a frequency not exceeding 500 Hz and a rated current not exceeding 800 A, primarily intended for industrial use, either indoors or outdoors.
This fifth edition cancels and replaces the fourth edition published in 1999, Amendment 1:2005 and Amendment 2:2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:

1. addition of classification, requirements and tests for accessories with shutters;
2. additional marking to indicate neutral terminal and/or earthing terminal;
3. replacement of the term "connector" by the term "portable socket-outlet".