Calibration – The Definition Calibration is the comparsion of measurement device or an instrument(device under test, DUT) against a known with equal or better standard. The standard in a measurement is considered to be more correct of the two and one would calibrate the device under test to know far it deviates from the standard. Usual calibration usually done by commercial calibration laboratories uses a manufacturer’s calibration procedure and is performed with a reference standard multiple times more accurate typically at four times with accuracy of the DUT. So, Why Do We Need to Calibrate? Having instruments that are calibrated insures quality output products. Out of tolerance (OOT) instruments tend to give wrong readings resulting in unnecessary back jobs and process failures. Bad or low quality products would pass as good ones resulting in warranty costs, and good products as non-conformance to quality ones, resulting to unnecessary reworks. So basically, calibrat...