Author(s)

R. S. M. Ali

Abstract

The Thin Film Multijunction Thermal Converter (TFMJTC) has become the most sensitive and precise transfer standard for the accurate measurement of the ac quantities. Therefore, its parameters are determined at the National Institute of Standards (NIS), Egypt, to obtain its best operating conditions. These parameters are short-term stability, settling time, dc response time, n-factor, input/output dc curve and frequency response. All these parameters are determined automatically by using LabVIEW programs. From the results, it is found that the TFMJTC stabilizes at time 50 sec. At this time it has accepted short-term drifting error, 29 ppm, which can be considered its settling time. It is also shown that the 5 sec. is the response time of the TFMJTC. It is also shown that the practical response of the TFMJTC is according to the square-law at the test voltage from 40% to 100% of the rated voltage and the ac voltage is converted to the output dc voltage in a true square-law response with negligible deviation from the theoretical results. It can therefore be used successfully in these test voltages. The TFMJTC has lower uncertainty in calibrating the ac signals. Keywords: AC-DC transfer standard, Thin Film Multijunction Thermal Converter, AC voltage calibration.

Keywords

AC-DC transfer standard, Thin Film Multijunction Thermal Converter, AC voltage calibration.