Systems of the third generation. Speed of expansion, low cost, absence of design jobs, absence of intermediate routers, installation of a measurement point in some minutes, suitability as for buildings with low density (countryside) –collect of data to the manual terminal, and for buildings with high density – multi-storey houses. Scalability – in process of increase in quantity of the established points they can be united in a network, and presence of clock – allows to have data on consumption with time intervals – hour and daily.