The inductive measuring method is applied to measure the number of ferromagnetic wear particles. The particles are accumulated on the head of the FE SENSOR which is equipped with a permanent magnet. The output signal in the range from 0 to 100% is interrelated to the amount of the distributed particles at the sensor surface. Fine particles (micrometer range) and coarse particles (millimeter range) can be distinguished. The data is continuously processed to the special unit DATALOGGER and stored to ensure effective evaluation.