to use a capacitive sensor, which is designed as a heating element antenna electrode

A capacitive sensor that is configured for connection between a heating element and a heating current supply includes a common mode choke (common mode choke CMC) for the alternating voltage type disconnecting the heating element from the heating current supply. The CMC comprises a first and a second inductively coupled windings, the first winding being intended for connection between a first connection point of the heating current and a first terminal point of the heating element and the second winding for connection between a second terminal of the heating element and a second connection point of the heating current is provided. The capacitive sensor further comprises a control and evaluation circuit for supplying an AC signal to the heating element via a measuring node for measuring a voltage and / or current through the sense node, and for deriving an impedance between the heating element and a counter electrode of the measurement. The CMC comprises a third winding which is inductively coupled to the first and second winding, wherein the third winding is operatively coupled to the measurement node.