Apparatus for monitoring electrical current

摘要

An apparatus used for monitoring electrical current 10, comprising a current transformer 12 acting as a magnetic field sensor producing a first signal 14, and an electric field sensor 20 producing a second signal 22. The signals from the magnetic field sensor and the electric field sensor are processed and used to determine the direction 24 of power transfer along the conductor 18. This may be done by determining a phase angle between the signals. The analogue signals from the sensors may be converted to a pulse train or digital signal and also be subject to attenuation. The apparatus may contain a Schmitt trigger. The apparatus may also contain a support to force the electric field detector and the conductor together. Alternatively the electric field sensor may be shaped to fit against the conductor. The apparatus may also contain a housing.