A sensor apparatus for an electrochemical measuring device. The apparatus has at least one electrode, which can be heated using a heating current in the form of an alternating current, and a first and a second connection for the supply line for the heating current. The electrochemical measuring device is connected to the electrode by a third connection. In this case, the apparatus has the third connection connected to the electrode by a bridge circuit, which is also connected to the first and second connections. There also is provided a method for carrying out electrochemical measurements at elevated temperature. The sensor apparatus and the method for carrying out electrochemical measurements enable electrochemical measurements with little interference and directly heated electrodes in conjunction with a simplified design of the electrodes.