Abstract: Methods for eliminating error in magnetic sensors used for measuring a coating thickness caused by static or changing external magnetic fields or temperature. The methods involve measuring an output voltage of a magnetic sensor, corresponding to an internal resistance of the magnetic sensor, in a static or changing magnetic field or external temperature, storing the value of the output voltage, performing mathematical operations with the stored value of the output voltage, and correcting the output voltage of the magnetic sensor to accurately indicate a coating thickness.

Abstract: A method which compensates errors resulting from offset voltages and external magnetic fields when a magnetic sensor is used to measure coating thickness. The method also allows compensation of a temperature dependent change for output voltages of the magnetic sensor.

Abstract: The subject of the invention is a coating thickness gauge with at least one measuring probe (14) which has at least one sensor (15, 15′) as well as a device for the zero adjustment and/or calibration. The coating thickness device (10) is equipped with means to automatically activate zero adjustment and/or calibration when an interaction especially a contact or a relative movement between a sensor (15, 15′) and a reference plate (11, 11′).