The first thing to consider is the underlying transducer technology. The most robust transducers rely on the magnetic properties of certain steels to produce a signal in response to the force applied – also known as the magnetoelastic effect. All ABB Pressductor® load cells are based on this principle. In contrast, many other systems rely on physical movement – essentially bending or stretching the measurement elements – to generate an electrical signal, making them more vulnerable in challenging operating conditions.
Pressductor® transducers rely on two perpendicular windings of copper wire running through four holes of a steel membrane. An electric current is applied to generate a magnetic field in one of the windings. When the transducer experiences a mechanical force, the magnetic properties of the magnetoelastic steel alter the magnetic flow pattern, inducing an AC voltage in the second coil that’s proportional to the force.
This technology copes naturally with overloads of 300 to 1,000 percent of the cell capacity, depending on the type of load cell, while the deflection under typical industrial loads is between just 0.02 to 0.05mm. That’s between 10 and 100 times less than the displacement typically experienced with movement-based devices.
Since ABB introduced Pressductor® technology, the added stability and service life provided by this robust approach has proved invaluable in paper mills and other tough environments such as steel production.