Abstract: An apparatus for detecting illegal tampering with an electricity meter which is adapted to record the amount of electricity supplied to the meter through cables has a first signal generating sensing coil situated externally of, and upstream of, the meter which generates a first signal representative of the current flowing through one of the supply cables and a second signal generating second sensing coil, located within the meter, which generates a second signal representative of the amount of electricity to be recorded by the meter. A Monitoring device monitors the first and second signals and produces a third actuation signal when one of the first and second signals differs from its correct value as a result of tampering.

Abstract: An apparatus for detecting illegal tampering with an electricity meter which is adapted to record the amount of electricity supplied to the meter through cables has a first signal generating sensing coil situated externally of, and upstream of, the meter which generates a first signal representative of the current flowing through one of the supply cables and a second signal generating second sensing coil, located within the meter, which generates a second signal representative of the amount of electricity to be recorded by the meter. A Monitoring device monitors the first and second signals and produces a third actuation signal when one of the first and second signals differs from its correct value as a result of tampering. The first and second signals charge and discharge a capacitor. When the voltage on the capacitor reaches a predetermined level, the third signal, which may cause the load to be disconnected or may produced a warning, is generated.