High accuracy AC current sources calibration by single junction thermal converters at INM?

摘要

The National Metrology Institute of Colombia (INM) uses high accuracy calibrators (such as Fluke 5720A/5730A) as AC current reference standards. We describe the implementation at INM of AC-DC current transfer standards by single junction thermal converters (SJTC) to improve the accuracy of AC measurements and give traceability to the International System of Units (SI) within the country. We describe the measurement model, present the uncertainty budget estimation accordingly to the Guide to the Expression of Uncertainty in Measurement (GUM) and analyze the effect of temperature and electrostatic on measurements. Expanded uncertainties between 68 繕A/A and 2.6 mA/A were obtained for the calibration of high accuracy calibrators and transconductance amplifiers for currents from 5 mA to 20 A (40 Hz to 5 kHz). The obtained measurement results are compatible with calibration results from the National Metrology Institutes like Centro Nacional de Metrolog穩a from Mexico (CENAM) and Accredited International Laboratories like Fluke.