The device has a measurement evaluation device (4), a sensor (2) for detecting an influencing parameter, and a signal pre-processor (3), in which the sensor outputs sensor signals (9) via an analogue sensor output. The signals are fed via the pre-processor to the measurement evaluation device. The signal pre-processor device contains a subtraction stage (11) for forming a difference signal (13) between the sensor signal (9) and the reference signal (10). The difference signal can be fed to a first analogue input of the evaluation device for evaluation.
