Eddy current sensor

If a conductive body is moved in a magnetic field, eddy currents occur in this field because a voltage is induced in the conductive material . With this principle, lengths and thicknesses of electrically conductive materials in the range between 0.5 mm and 140 mm can be determined. These sensors belong to the class of non-contact distance meters.

Eddy current sensors are insensitive to media such as oil, water and dust in the measuring gap. They only react to metals in this gap.

Since the electromagnetic induction in coils produces a voltage that is proportional to the rate of change of the magnetic flux, the principle can also be used for speed measurement with eddy current sensors or e.g. B. useful with tacho generators.