Applies to electromechanical elementary relays (non-specified time all-or-nothing relays) for incorporation into equipment. Defines the basic functional requirements and safety-related aspects for applications in all areas of electrical engineering or electronics. Compliance with the requirements of this standard is verified by the type tests indicated. The main changes with respect to the previous edition comprise: inclusion of contact load categories (same as in IEC 61810-2 and IEC 61810-7); clarifications concerning electrical endurance; inclusion of provisions for insulation coordination in accordance with the basic safety standards; inclusion of new annexes for the test set-up, and for special loads.