The invention relates to a measuring circuit. The measuring circuit comprises a sensing element configured to generate a measuring signal from a measuring object, a signal injector configured to generate an auxiliary signal, and an evaluation circuit comprising a first upstream amplifier with a first input connected to a first pole of the sensing element via a first signal line and a second upstream amplifier with a first input connected to a second pole of the sensing element via a second signal line. A measuring circuit with an improved reliable control of its measuring chain allowing continuous testing of the integrity of the measurement signal coming from the sensing element and/or to allow the measuring circuit to be upgradable with respect to a different sensing unit and/or evaluation unit, the first upstream amplifier comprises a second input connected to the signal injector, and the evaluation circuit comprises a first downstream amplifier having a first input connected to the signal injector and a second input connected to an output of the first upstream amplifier.