IEC 60352-4:2020 is applicable to non-accessible ID connections for which the tests and measurements according to Clauses 6 through 8 are suitable and which are made with: – appropriately designed ID terminations; – wires having solid round conductors of 0,25 mm to 3,6 mm nominal diameter; – wires having stranded conductors of 0,05 mm2 to 10 mm2 cross-sectional area; for use in electrical and electronic equipment and components. Information on materials and data from industrial experience is included in addition to the test procedures to provide electrically stable connections under prescribed environmental conditions. There are different designs and materials for ID terminations in use. For this reason, only fundamental parameters of the termination are specified, while the performance requirements of the wire and the complete connection are specified in full detail. The purpose of this document is: – to determine the suitability of non-accessible ID connections under specified mechanical, electrical and atmospheric conditions; – to provide a means of comparing test results when the tools used to make the connections, if any, are of different designs or manufacture. This second edition cancels and replaces the first edition, published in 1994, and its Amendment 1 (2000). This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) Transferred Clauses 9 to 13 into Annex A (informative). b) The figures were re-drawn for clarity.