DIGITAL WATT-HOUR METER FORTELEMETERING INCLUDING INDEPENDENT GROUND INNER IN AUTOMATIC METER READING SYSTEM

摘要

An electronic kilowatt-hour meter system for telemetry having an independent ground is provided to prevent an erroneous operation due to an abnormal state of a ground level potential by generating a voltage difference by separately connecting a ground pattern according to voltage. In an electronic kilowatt-hour meter system for telemetry composed of an electronic kilowatt-hour meter and a telemetry device, power supply units(102,103) of the electronic kilowatt-hour meter and the telemetry device are connected to independent grounds, respectively. The ground includes a digital ground for +12V and a digital ground for +5V. The power supply unit of the electronic kilowatt-hour meter is connected to the digital ground for +5V or +3.3V, and the power supply unit of the telemetry device is connected to the digital ground for +12V.