Honeywell's closed loop current sensors consist of a Hall-effect sensor mounted in an air gap of a magnetic core, a coil wound around the core and a current professional amplifier. The current carrying conductor placed through the aperture of the sensor produces a magnetic field that is proportional to the current. The core concentrates the magnetic field which is measured by the Hall sensor. The Hall sensor is connected to the input of the current amplifier, which drives the coil. The current through the coil produces an opposing field to that provided by the current through the aperture. The magnetic flux in the sensor core is constantly controlled at zero. The amount of current required to balance zero flux is the measure of the primary current flowing through the conductor, multiplied by the number of turns on the coil. This current can be expressed as a voltage by passing it through a resistor. Variety of package styles available.
Best Used For:
Applications requiring high linearity and accuracy, fast response and low temperature drift such as variable speed drives, overcurrent protection, current feedback control systems, robotics and welding power supplies.
