Systems of the third generation. Speed of expansion, low cost, absence of design jobs, absence of intermediate routers, installation on the 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.