Title :
Guarded vector voltmeter for AC ratio standard calibration
Author :
Callegaro, Luca ; D´Elia, Vincenzo
Author_Institution :
Dept. of Electr. Metrol., Ist. Elettrotecnico Nazionale Galileo Ferraris, Torino, Italy
Abstract :
A new setup for the calibration of the ratio of inductive voltage dividers against a ratio standard is under development at IEN. The setup is based on the direct measurement of voltage vector differences between the device under test and the standard, with a purposely-built vector voltmeter described. The uniqueness of the voltmeter is the extremely high common-mode-rejection-ratio (CMRR), greater than 180 dB at I kHz, obtained with a bootstrapping-guarding technique. The voltmeter is battery-operated has variable gain and a dual-channel synchronous demodulating stage with high harmonic rejection, is operated with a personal computer via an optical-fiber interface
Keywords :
calibration; computerised instrumentation; measurement standards; voltage dividers; voltage measurement; voltmeters; 1 kHz; 180 dB; AC ratio standard calibration; C environment; IEN; bootstrapping-guarding; coaxial circuit; common-mode-rejection-ratio above 180 dB; direct measurement; dual-channel synchronous demodulating stage; guarded vector voltmeter; harmonic rejection; inductive voltage dividers; optical-fiber interface; personal computer application; Calibration; Gain; Measurement standards; Microcomputers; Optical computing; Standards development; Testing; Ultraviolet sources; Voltage measurement; Voltmeters;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 2001. IMTC 2001. Proceedings of the 18th IEEE
Conference_Location :
Budapest
Print_ISBN :
0-7803-6646-8
DOI :
10.1109/IMTC.2001.929442
