Specifies requirements for plugs, socket-outlets, cable couplers and appliance couplers (primarily intended for general industrial use either indoors or outdoors) for operation at 50 Hz with a rated voltage not exceeding 660 V and rated current not exceeding 315 A. Gives both general and specific requirements for accessories with pins and contact tubes of standardized configuration. Based on the principles, but not the format, of IEC 309, although the layout is similar.