A measuring apparatus for sensing metal articles, comprises a transmission coil for producing a magnetic field, two reception coils, which are oriented relative to one another, and electrically connected to one another, in the region of the magnetic field such that a resulting received voltage on the reception coils is zero when the magnetic field acts on both reception coils in the same way, a control device configured to supply the transmission coil with an alternating transmission voltage, and a determination device configured to determine the metal article on the basis of the received voltage. In this arrangement, the control device is further configured to control RMS value for the transmission voltage such that the received voltage remains below a predetermined threshold value.