AC shunt calibrations at NRC

NRC offers calibration of ac shunts from milliamperes up to 100 A, in the 10 Hz to 100 kHz frequency band with expanded uncertainties between 10 A/A for currents in the milliampere range to 50 A/A at 100 A and 100 kHz. The paper describes the design of NRC ac standard shunts, as well as NRC experience in calibrations of commercial shunts. The ac-dc difference of some commercial low current shunts is load sensitive at higher frequency ranges. The paper discusses reasons for this sensitivity and suggests mitigating solutions.Peer reviewed: YesNRC publication: Ye