Thermal energy meters - Part 3: Data exchange and interfaces

This document specifies the general requirements of data exchange and interfaces for thermal energy meters. This document is applicable to unidirectionally and bidirectionally transmitting thermal energy meters. This document applies also to networks with up to 250 meters, for which a master unit with AC mains supply is necessary to control the M-Bus. In these cases, the document is only applicable in conjunction with EN 13757-2 (physical and link layer) and EN 13757-3 (application layer). For wireless thermal energy meter communications, this document is only applicable in conjunction with EN 13757-4, which describes several alternatives of walk/drive-by readout via a mobile station or by using stationary receivers or a network. NOTE Thermal energy meters are instruments intended for measuring the energy which in a heat-exchange circuit is absorbed (cooling) or given up (heating) by a liquid called the heat-conveying liquid. The meter indicates thermal energy in legal units.