Industrial Applications of Hall-Effect Devices

The Hall effect can be employed to obtain an output proportional to the product of the current through the element and the field cutting through it. A qualitative explanation aids in the visualization of the phenomena. There are several semiconductor materials that may be selected to emphasize a particular characteristic such as power transfer, temperature stability, etc. Maximum efficiency and improvement of dynamic range can be realized if care is taken in the assembly of the element-magnet structure and appropriate compensation techniques are employed. Since the two inputs are current and flux density and these may result from a variety of sources, the application becomes multitudinous. This creates an entirely new family of transducers that in many cases are improved in size, response and cost over conventional devices. The following applications are described: wattmeter, varmeter, gaussmeter, clip-on ammeter, resolvers and synchros, and magnetic tape readers.