Over the course of time, every measuring instrument will display changing measured values. This is because instruments age through the influence of mechanical, chemical or thermal stresses. Through calibration, this can be detected in good time. It is thus essential to calibrate Pt100/Pt1000 resistance thermometers at regular intervals. The calibration of temperature measuring instruments is fundamentally different from the procedure for pressure measuring instruments. Often, thermometers are only calibrated at a single fixed point. This could be, for example, the triple point of water. For the calibration of Pt100/Pt1000 temperature sensors, their, usually very well-known, characteristic curve is then shifted downwards or upwards so that the temperature measuring instrument shows the correct value at the fixed point. Industrial thermometers are usually calibrated with a higher-quality measuring instrument. This is often done with immersion baths or furnaces. As soon as a thermal equilibrium between the Pt100/Pt1000 resistance thermometers and the bath liquid has settled, the display (or the output signal) of the test items is compared with that of the standard thermometer. In particular, this scenario is very popular on-site, where one uses dry-well calibrators . You can find out more about calibration at WIKA in our service area .