IEC 62056-6-2:2017 specifies a model of a meter as it is seen through its communication interface(s). Generic building blocks are defined using object-oriented methods, in the form of interface classes to model meters from simple up to very complex functionality. Annexes A to F (informative) provide additional information related to some interface classes. This third edition cancels and replaces the second edition of IEC 62056-6-2 published in 2016. It constitutes a technical revision. The significant technical changes with respect to the previous edition are listed in Annex F(Informative).