DIN EN IEC 62391-1:2024-04

This part of IEC 62391 applies to fixed electric double-layer capacitors (hereinafter referred to as capacitor(s)) mainly used in DC circuits of electric and electronic equipment. This document establishes standard terms, inspection procedures and methods of test for use in sectional and detail specifications of electronic components for quality assessment or any other purpose. Essential terms for application of the document are explained and defined in the clause Terms. In this context, the type is a group of components with the same design characteristics and the same structure, which can be grouped together for type approval testing and quality assessment control due to similar manufacturing techniques. The style is a subset of a type, generally based on specific dimensions; a type may include several embodiments, generally differing in mechanical details. The DC capacitor is a capacitor essentially designed for use with DC voltage. The rated capacitance is the capacitance value for which the capacitor is designed and which is usually indicated on it. The rated voltage is the highest DC voltage or peak pulse voltage that may be continuously or repeatedly applied to the capacitor at temperatures between the lower category temperature and the rated temperature. The clause Test and Measurement Requirements explains the test conditions. The sectional specification and/or the blank detail specification shall contain information on which tests are to be carried out, which measurements are to be taken before and after each test or subgroup of tests, and in what order they are to be carried out. The steps of each individual test shall be carried out in the specified order. The measurement conditions for initial and final measurements shall be the same. The following clauses deal with electrical tests and measurements, mechanical tests and measurements, environmental and climatic tests, tests relating to component assembly, safety-related tests, and quality assessment procedures. The normative Annex A describes the classification of capacitors according to their capacitance and internal resistance value depending on the application. The measurements of capacitance and internal resistance according to the constant current discharge method and the direct current resistance method, respectively, require longer measurement times depending on the rated values of the product, provided that the measurement conditions are standardized with the degree of accuracy of these measurement methods. Informative Annex B contains measurement methods for capacitance and low resistance using the low frequency AC method (reference method); Informative Annex C describes the thermal equilibrium time of capacitors (thermal equilibrium setting time) and of capacitors as a reference value when determining the thermal soaking period for pretreatment. Informative Annex D explains the general concept of charging and discharging efficiency and measuring current. Informative Annex E contains the procedure for setting the measuring current for a capacitor with unknown nominal internal resistance.