Current sensor challenges Hall devices
A company based in Essex, UK, has developed a non-contact current-monitoring device that can measure DC and AC currents at any voltage and from mA to kA, with a claimed sensitivity of 30µA in 1A. Fluxgate World says that its loss-free device, which can measure currents at frequencies up to around 100Hz, has advantages over other types of sensors, such as Hall Effect devices.
The conductor carrying the current to be sensed is threaded through a coil (called the fluxgate) on a 50mm2 printed circuit board that carries the control electronics. A "null balance" principle is used to balance the magnetic field produced by the current.
The device is claimed not to dissipate heat, thus eliminating thermal effects and improving stability. Fluxgate has developed two- and three-axis versions of the device.
