Utility monitoring and control system

A system for the communication, between a central use information bank and plural end user sites within a utility distribution system, of utility use information indicative of utility use at the plural end user sites, such system comprising

• interface menas for interfacing the use information bank with a communication ink independent of power lines of said utility distribution system,
• a least one relay module including means for communicating information along the communications link with the information bank, and means for communicating information via power line carrier with a plurality of site units at plural end user sites, and
• a plurality of site units, each located at a specific end user site and responsive at an address signal transmitted by power line carrier from a specific said relay module, for transmitting utility use information of the specific end user site by power line carrier to said specific relay module,
• wherein each said site unit communicates with a single said relay module, and each said relay module is located at a distribution transformer and connected to the secondary side thereof so as to communicate with a plurality of nearby site units, each located at a site receiving power through the said transformer.

A control module for controllably communicating with a plurality of PLC-addressable utility usage units, such module comprising

• interface means for receiving and sending communications over a first, external, communications link to a central information source
• polling means for polling over a second, PLC, communications link, a plurality of utility usage units in power line communication with the module so as to communicate usage information to said units and receive usage information from said units
• storage means for storing usage information, and
• relay control means for controlling the interface means, the storage means and the polling means so as to relay utility usage information between said central source and said plurality of utility usage units.

A relay module for controllably communicating with a plurality of PLC-addressable utility usage units, such module comprising

• interface means for receiving and sending data over a first communications link independent of power lines, to a central information source,
• polling means for polling over a power line communications link, a plurality of separately addressable utility usage units in power line communication with the relay module so as to communicate data to said units and receive data from said units,
• storage means for storing said data, and
• relay control means for controlling the interface means, the storage means and the polling means so as to relay utility usage information between said central source and said plurality of utility usage units by successively polling said plurality of usage units, storing data received therefrom, and subsequently communicating the stored data as a block of data via said interface means.