ELECTRONIC ELECTRICITY METER

摘要

An electronic electricity meter which, in one embodiment, includes a modem board, or unit, coupled to the meter microcomputer (20) and exchanges information between the meter (10) and a central computer (58) is described. Using signals supplied by the meter microcomputer (20) and the central computer (58), the modem unit (50) microcomputer can determine whether to exchange information between the meter and the central computer (58) and the proper time at which the information should be exchanged. In an exemplary embodiment, the modem unit (50) detects various conditions within the meter and responds by exchanging information with the central computer (58) at a proper, or pre-defined, time. The modem unit has two different basic modes, or states, of operation. These states of operation are sometimes referred to as the call originate mode and the call answer mode. Call originate refers to the mode of the unit when a condition occurs in meter 10 and information is being transmitted to the central computer (58) from the modem unit (50) utilizing a telephone line. The call is originated upon occurrence, for example of a power outage to the meter. In the call answer mode, the central computer originates a call to the meter. The central computer (58) can then transfer information to the meter, for example a new program can be stored in the modem unit memory.