Magnetic sensing allows for a large gap between sensing unit and material measure (usually a magnetic ring). This allows for positioning separated from each other eliminates the need for the conventionally required precision ball bearings. In parallel, it allows for rather high mounting tolerances. This provides more flexibility in design and installation. As there is no need for bearings, there is no conventional wear and tear either. This way the encoders withstand dust, dirt or textile fibers. They are immune to shaft currents or bearing loads and robust against vibration and shock.