This work registers the characterization of the transmission of data in the electric net, through an automatic system of device control saw net of electric feeding, will be described the involved protocols and concepts technician in the project. The work approaches the research and development aiming at to the characterization of a control system that uses the electric net of low existing tension as media and that it will be constituted of: a main unit, that sends the commands them devices to be controlled; a white unit, where the devices properly said (as household-electric cameras, devices, etc.) for the communication with the main unit will be connected. The modem used for the development contains integrated circuits special that condition and treat the signals proceeding from the electric net and manage (for half of protocol) all the communication process enters the units of the system. The development provides a clear vision with relation of the use of the electric net as half data-communication; approaching cost x benefit in the use of conventional handles or use of an existing structure already (electric net), beyond opening a fan of new procedures and alternatives of nets for new models of traffic of data. Word-key: Automation, Electric Net, Protocol, Interface, Electronics.
1. Introduction This work characterizes to the use of handles of the electric net, for transmission of data and information between devices; the idea to send electric signals for the communication in the same cabeamento of the net of electric energy is so old how much the proper telegraph, the installed device number of communication with dedicated cabeamentos exceeds the installed device number very that uses electric net AC (Current Alternated) as half of transmission. One of the great problems in the transmission of data in nets of electric energy is the injection of carriers high-frequency, necessary to reach adequate taxes of communication to the residential, commercial and industrial automation. The net of electric energy, as well as its components (transforming, capacitors, lines of transmission, engines, etc.) has its settled project so that it has a bigger efficiency in the frequency clock of 60Hz, or in other words, the electric net is projected to supply power, and it does not stop transmitting given.