BS EN 60384-18:2009 pdf download – Fixed capacitors for use in electronic equipment — Part 1 8: Sectional specification — Fixed aluminium electrolytic surface mount capacitors with solid (Mn02) and non-solid electrolyte
3 Quality assessment procedures
3.1 Primary stage of manufacture For capacitors with solid electrolyte, the primary stage of manufacture is the etching or formation of the anode body. For capacitors with non-solid electrolyte, the primary stage of manufacture is the capacitor manufacturer’s evaluation of the formed anode foil.
3.2 Structurally similar components Capacitors considered as being structurally similar are capacitors produced with similar processes and materials, though they may be of different case sizes and values.
3.3 Certified records of released lots The information required in 3.9 of IEC 60384-1 shall be made available when prescribed in the detail specification and when requested by a purchaser. After the endurance test the parameters for which variables information is required are the capacitance change, tan δ and the leakage current.
3.4 Qualification approval procedures The procedures for qualification approval testing are given in 3.5 of the generic specification, IEC 60384-1 . The schedule to be used for qualification approval testing on the basis of lot-by-lot and periodic tests is given in 3.5 of this specification. The procedure using a fixed sample size schedule is given in 3.4.1 and 3.4.2 below.
3.4.1 Qualification approval on the basis of the fixed sample size procedure Sampling The fixed sample size procedure is described in 3.5.3b) of IEC 60384-1 . The sample shall be representative of the range of capacitors for which approval is sought. This may or may not be the complete range covered by the detail specification.
The sample shall consist of specimens having the lowest and highest voltages and for these voltages the smallest and largest case size. When there are more than four case sizes, an intermediate case size shall also be tested. In each of these case size/voltage combinations (values), the highest capacitance shall be chosen. Thus, for the approval of a range, testing is required of either four or six values. When the range consists of less than four values, the number of specimens to be tested shall be that required for four values. Spare specimens are permitted as follows:
a) one per value which may be used to replace the permitted nonconforming item in Group 0;
b) one per value which may be used as replacements for specimens which are nonconforming because of incidents not attributable to the manufacturer. The numbers given in Group 0 assume that all groups are applicable. If this is not so, the numbers may be reduced accordingly. When additional groups are introduced into the qualification approval test schedule, the number of specimens required for Group 0 shall be increased by the same number as that required for the additional groups. Table 2 gives the number of samples to be tested in each group or subgroup together with the permissible number of non-conforming items for qualification approval tests.
3.4.2 Tests The complete series of tests specified in Tables 2 and 3 are required for the approval of capacitors covered by one detail specification. The tests of each group shall be carried out in the order given. The whole sample shall be subjected to the tests of Group 0 and then divided for the other groups. Specimens found to be nonconforming during the tests of Group 0 shall not be used for the other groups. “One nonconforming item” is counted when a capacitor has not satisfied the whole or part of the tests of a group. The approval is granted when the number of nonconforming items does not exceed the specified number of permissible nonconforming items for each group or subgroup and the total number of permissible nonconforming items.
NOTE Tables 2 and 3 together form the fixed sample size test schedule, for which Table 2 includes the details for the sampling and permissible nonconforming items for the different tests or groups of tests, whereas Table 3, together with the details of tests contained in Clause 4, gives a complete summary of test conditions and performance requirements and indicates where, for example, for the test method or conditions of test, a choice is made in the detail specification. The conditions of test and performance requirements for the fixed sample size test schedule should be identical to those prescribed in the detail specification for quality conformance inspection.