Extrusion International 4-2017

32 Extrusion International 4/2017 MEASUREMENT Zumbach – (Self)compensation of Measuring Units Increases Accuracy of Measurements Calibration in measurement technology means characterizing the measurement behaviour of a measuring unit by comparing the indications provided by the unit with a known “measurement standard” (a physical object) used in the calibration procedure. During the calibration, the measuring instrument is not subject to changes, as opposed to adjustmentwhereameasuringunit is tunedormodified inorder tominimize themeasurement errors or to guarantee that the measurement errors do not exceed predetermined bounds. Verification in legal metrology, however, pertains to the examination and marking and/or issuing of a verification certificate for a measuring system. The examining authority thus verifies whether the measuring unit satisfies the corresponding legal prerequisites. Typical ODAC ® laser diameter measuring gauge with a certifiedmeasurement standard used to calibrate the device