During the tachometer calibration process, the instrument is compared against a known reference source, typically a speed standard, to ensure that it is measuring accurately. The calibration process involves a series of tests at different speed levels, and the results are compared with the reference values. Calibration certificates are then provided to document the calibration process and results, providing traceability and peace of mind for the customers.

It is important to have regular calibration of tachometers to ensure accurate speed measurements, as the accuracy of the instrument can drift over time. The frequency of calibration depends on several factors, including the industry, application, and the frequency of use. Typically, tachometers should be calibrated at least once a year, but some applications may require more frequent calibration.