The present technology involves a method and apparatus for detecting and reporting
magnetic fields in the proximity of a utility meter as an approach to determining
tampering of such meter. The sensitivity level of the magnetic field sensors may
be adjustable allowing either remote or local sensitivity adjustments to a magnetic
field sensor to compensate for variations in the electromagnetic environments of
different meter installation sites. Alternatively, the output of each magnetic
field sensor may be connected to the input of an adjustable threshold circuit.
When the output voltage of the magnetic field exceeds a predetermined threshold
voltage, a magnetic event signal is generated. Threshold adjustments to the adjustable
threshold circuit may be performed locally at the meter site or remotely from a
station. The output of each magnetic field sensor may be monitored by a locally
or remotely programmable magnetic sensor output monitor. Such magnetic sensor output
monitor generates a magnetic event signal when a predetermined number of magnetic
sensors have been activated.
