Current clamp calibration involves a series of tests to verify the accuracy of the instrument. The current clamp is compared against a known reference source to ensure that it is measuring correctly. The calibration process includes tests at several current levels, and the results are compared with the reference values. If necessary, adjustments are made to the current clamp to bring it back to its original calibration. Calibration certificates are then provided to document the calibration process and results, providing traceability and peace of mind for the customers.