Solid state watt-hour meter using GMR sensor

摘要

A power consumption meter is disclosed for measuring the power consumed by a load on a power conductor, wherein the electronics of the power consumption meter are isolated from lightning and power transients. The meter has a first GMR sensor that is disposed proximate the power conductor and is magnetically coupled to the power conductor. The first GMR sensor detects magnetic flux in the power conductor and produces a first output responsive to the detected magnetic flux that is representative of the current flowing through the power conductor. A second GMR sensor is disposed proximate the power conductor and is magnetically coupled to the power conductor. The second GMR sensor detects magnetic flux in the power conductor and produces a second output responsive to the detected magnetic flux that is representative of the voltage on the power conductor. A processor is operably communicatively coupled to the first and second GMR sensors and is responsive to the first output and the second output for producing a third output that is representative of the energy consumption of the load on the power conductor. In an embodiment, a third GMR sensor provides feedback for auto-scaling of the first GMR sensor.