Frequency Extension of the NIST AC-DC Difference Calibration Service for Current

摘要

The NIST calibration service for ac-dc difference of thermal current converters (TCCs) relies on primary multijunction thermal converters (MJTCs), reference, and working-standard thermal converters and thermoelements (TEs). Calibrations are performed by the comparison of the ac-dc difference of a customer's thermal current converter with the ac-dc difference of a NIST standard. Typical artifacts accepted for calibration include single-junction thermoelements, multijunction thermal converters, and transfer shunts for use with thermoelements. This paper describes the standards on which the calibration service is based and the results of the study underway to characterize the NIST standards over the extended frequency range from 10 Hz to 100 kHz at currents up to 20 A.