Circuit for detecting AC current over large range - has transformer driving bistable circuit with rectangular wave detector

摘要

The transformer (UE) has its primary winding connected in the current path of the measurement line and its secondary winding connected to an evaluation circuit. The transformer has a very small, high permeability core. The evaluation circuit contains a bistable circuit (BS) triggered by the voltage pulses induced in the secondary winding and which stores its polarity until the next pulse arrives. A rectangular wave a.c. voltage is detected (MF) at the bistable output. USE/ADVANTAGE - For detecting a.c. current in line over large current magnitude range without significant losses or large voltage drops.