BS 61191-4:2017 pdf download – Printed board assemblies Part 4: Sectional specification – Requirements for terminal soldered assemblies (IEC 61191-4:2017)

BS 61191-4:2017 pdf download – Printed board assemblies Part 4: Sectional specification – Requirements for terminal soldered assemblies (IEC 61191-4:2017) 1 Scope This part of IEC 61191 prescribes requirements for terminal soldered assemblies. Therequirements pertain to those assemblies that are entirely terminal/wire interconnectingstructures or to the terminal/wire portions of those assemblies that include other relatedtechnologies (i.e. surface mounting, through-hole mounting, chip mounting). 2Normative references The following documents are referred to in the text in such a way that some or all of theircontent constitutes requirements of this document.For dated references,only the editioncited applies.For undated references, the latest edition of the referenced document (includingany amendments) applies. IEC 60194,Printed board design,manufacture and assembly – Terms and definitions IEC 61191-1:2013，Printed board assemblies – Part 1: Generic specification – Requirementsfor soldered electrical and electronic assemblies using surface mount and related assemblytechnologies 3Terms and definitions For the purposes of this document, the terms and definitions given in lEC 60194 apply. lSo and lEC maintain terminological databases for use in standardization at the followingaddresses: · IEC Electropedia: available at http://www.electropedia.orgl . IsO Online browsing platform: available at http://www.iso.orglobp 4General requirements Requirements of lEC 61191-1 are a mandatory part of this specification. Workmanship shall meet the requirements of lPC-A-610 in accordance with the classificationrequirements of this document. 5 General terminal and part mounting requirements 5.1 General The requirements of 5.2 are applicable to terminals and part mounting in all types ofassembiies. 5.2 Wire and cable preparation 5.2.1 General Sufficient insulation cover shall be stripped from the wire or leads to provide for insulation clearances as specified. Chemical stripping agents shall be used for solid wire only and shall be neutralized or removed prior to soldering. In stripping insulation, care should be taken to avoid nicking or otherwise damaging the wire or the remaining insulation. For level A or B assemblies, the number of nicked or broken strands in a single wire shall not exceed the limits given in Table 1 . For wires used at a potential of 6 kV or greater, or for level C assemblies, there shall be no broken strands. The number of nicked strands shall be in accordance with Table 1 . Insulation discolouration resulting from thermal stripping is permissible. 5.2.2 Tinning of stranded wire Portions of stranded wire to be soldered shall be tinned prior to mounting. The solder shall wet the stranded wire and penetrate to the inner strands of the...