Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO) IEC 61439-3:2024 CMV contains both the official standard and its commented version. The commented version provides you with a quick. In collaboration with the distribution system operators, Swissgrid ensures that all the necessary contracts, processes and regulations for secure and reliable operation and non-discriminatory use of the electricity grid are in place. The technical content of IEC publications is kept under constant review by the IEC. 0 and the previous IEC 61439-3:2012 edition 1. Furthermore, comments from IEC TC SC 121. All equipment and installations connected to the Swiss power grid must fulfil the requirements in the documents listed on this page at all times. The Swiss laws are purposely not very detailed in order to allow companies in the industry sectors concerned to find the most efficient solutions. - assemblies for indoor or outdoor use. This second edition cancels and replaces the first edition published in 2012.