DMDC 1.2 is a smart data concentrator, which is used for automatic measuring instrument data collection in multiple energy resource metering systems. DMDC reads data using PLC communication technologies and transmits data using Ethernet or GPRS/3G communication. The data concentrator is saving the collected data and transmits it to the data collection center on external request. DMDC 1.2 are most often used in residential district or residential building energy resource metering system when there is a need to connect a big number of electricity meters and the cabling of communication line is economically inefficient.