ABB's Pressductor Technology produces a signal as a result of changes in an electromagnetic field when the sensor is subjected to mechanical force.
It is an operating principle that has its origin in a metallurgical phenomenon according to which mechanical forces alter the ability of some steels to convey a magnetic field. Unlike other types of sensor (transducer) technologies, physical movement such as compression, bending and stretching is not required for signal generation.
The pressure sensor is a simple and elegant design. Essentially, two perpendicular windings of copper wire around a steel core combine to provide a measurement signal.
An electromagnetic field is created by continuously feeding an alternating current to the primary winding. The field is positioned in such a way that, since the windings are at right angles to each other, there are no magnetic coupling between them when the sensor is unstressed.
However, when the sensor is subjected to a pressure, as shown in the figure, the magnetic field pattern changes. A portion of the field couples with the secondary winding and induces an AC voltage that reflects the cylinder pressure. This voltage - a comparatively strong sensor signal - is converted by the sensor electronic unit to a DC voltage that is proportional to the cylinder pressure.
ABB's Pressductor transducer stands for unbeatable load cell performance, thanks to its unique combination of accuracy, overload capacity and ability to withstand harsh environments. By using this technology you will achieve higher quality and reliability, especially under demanding conditions.