Test instrument and method for calibrating a test instrument

摘要

The invention relates to a test instrument for testing a material web and to a calibration method for the test instrument. The test instrument is equipped with drive means for transporting the calibration medium past the test instrument in order to detect a multiplicity of measured values of the calibration medium. The drive means are arranged in the housing of the test instrument, such that the drive means are protected against humidity or contaminants from the surroundings. In order to enable the transportation of the calibration medium past the test instrument despite the arrangement of the drive means in the housing, drive means are used that are designed for non-contact interaction with the calibration medium and are able to transport the calibration medium past the test instrument without contact. For this purpose, a magnetic interaction between the drive means and the calibration medium is used preferably.